WO2004006862A2

WO2004006862A2 - A method for the modulation of angiogenesis

Info

Publication number: WO2004006862A2
Application number: PCT/US2003/022283
Authority: WO
Inventors: Shmuel Ben-Sasson
Original assignee: Children's Medical Center Corporation
Priority date: 2002-07-16
Filing date: 2003-07-16
Publication date: 2004-01-22
Also published as: WO2004006862A3; AU2003251968A1; AU2003251968A8

Abstract

The present invention concerns a method for modulation (increase or decrease) of angiogenesis by the contact of the blood vessels with compounds derived from specific regions of various kinases.

Description

A IMETHOD FOR THE MODULATION OF ANGIOGENESIS

FIELD OF THE INVENTION

The present invention concerns a method for the regulation (increase or decrease) of angiogenesis.

BACKGROUND OF THE INVENTION

The term "angiogenesis" (also referred to at times as "neovascularization") is a general term used to denote the growth of new blood vessels both in normal and pathological conditions.

Angiogenesis is an important natural process that occurs during embryogenesis, and in the adult healthy body in the process of wound healing, and in restoration of blood flow back into injured tissues. In females, angiogenesis also occurs during the monthly reproductive cycle to build up the uterus lining and to support maturation of oocytes during ovulation, and in pregnancy when the placenta is formed, in the process of the estabhshment of circulation between the mother and the fetus. The healthy body controls angiogenesis through the interactions of mgiogenesis-stim ating growth factors, and angiogenesis inhibitors, and the balance between the two determines whether angiogenesis is turned "on" or "off'. i the therapeutic field, there has been in recent years a growing interest in the control of angiogenesis. By one aspect, the aim was to control or diminish excessive and pathological angiogenesis that occurs in diseases such as cancer, diabetic blindness, age related macular degeneration, rheumatoid arthritis, psoriasis, and some additional 70 conditions. In these pathological conditions the new blood vessels feed the diseased tissue, for example the tumor tissue, providing it with essential oxygen and nutrients thus enabling its pathological growth. In addition the pathological angiogenesis many times destroys the normal tissue. Furthermore, the new blood vessels, formed for example in the tumor tissue, enable the tumor cells to escape into the circulation and metastasize in other organs. Typically, excessive angiogenesis occurs when diseased cells produce abnormal amounts of angiogenetic growth factors, overwhelming the effect of the natural angiogenesis inhibitors present in the body.

Anti-angiogenetic therapies developed today, are aimed at preventing new blood vessel growth through the targeting and neutralization of any of the stimulators that encourage the formation of new blood vessels.

A contrasting indication of regulating angiogenesis is the stimulation of production of neovascularization in conditions where insufficient angiogenesis occurs. Typically, these conditions are diseases such as coronary artery diseases, stroke, and delayed wound healing (for example in ulcer lesions). In these conditions, when adequate blood vessels growth and circulation is not properly restored, there is a risk for tissue death due to insufficient blood flow. Typically, insufficient angiogenesis occurs when the tissues do not produce adequate amounts of angiogenetic growth-factors, and therapeutic angiogenesis is aimed at stimulating new blood vessels' growth by the use of growth factors or their rnimics. The main goal of the angiogenesis therapy is to produce a biobypass - i.e., to physically bypass diseased or blocked arteries, by tricking the body into bunding new blood vessels.

Tie 2 is a receptor tyrosine-kinase for the endothehum growth factor angiopoietin 1&2. Tie-2 has bee shown to be involved in tumor related angiogenesis. Disruption of Tie-2 function in transgenic mice resulted in embryonic lethahty secondary to characteristic vascular defects; similar defects occurred after disruption of the Tie-2 ligand. These findings indicate that the Tie2/Tie2 ligand pathway plays important roles during development of the embryonic vasculature. Thus inhibition of this pathway, for example by a soluble fragments ofthe Tie-2 receptor has been aimed as a strategy for the inhibition of angiogenesis.

The eukaryotic protein kinase super family is composed of enzymes that use the gamma phosphate of ATP or GTP to specifically phosphorylate serine, threonine or tyrosine residues of intracellular proteins. Many of the kinases are involved in signal transduction in multicellulai- organisms in a variety of cellular events. Kinases were found to be involved in a wide range of physiological phenomena including: cellular proliferation, cellular differentiation, ontogenesis, immune response and inflammatory responses.

Undesired kinase activity has been found to be involved in proliferation-based diseases such as cancer; in non-mahgnant proliferative diseases such as arteriosclerosis and psoriasis; and in inflammatory responses such as septic shock. Malfunction of kinase activity has also been found to be involved in metabolic pathologies manifested by the decrease in the activity of msulin receptor kinase, such as in various types of diabetes. Agents that can modulate (by increasing or decreasing) the activity of protein kinases have a potential for the treatment of a wide variety of diseases and disorders including: cancer, autoimmune diseases, inflammation, injury, metabolic disorders, genetic disorders and the like. . -

PKs are known to have homologous "kinase domains" or "catalytic domains" which are responsible for the phosphorylation activity. Based on a comparison of a large number of protein kinases, it is now known that the kinase domain of protein kinases can be divided into twelve subdomains. These are regions that are generally uninterrupted by large amino acid insertions and contain characteristic patterns of conserved residues (Hanks and Hunter, "The Eukaryotic Protein Kinase Superfarnily", in Hardie and Hanks ed., The Protein Kinase Facts Book, Volume I, Academic Press, Chapter 2, 1995). These subdomains are referred to as Subdomain I through Subdomain XII.

Due to the high degree of homology found in the subdomains of different protein kinases, the a ino acid sequences of the domains of different PKs can be ahgned. Frequently, the alignment is with reference to the prototypical protein kinase PKA-C α, as known in the art. Currently, the catalytic domains of a large number of protein kinases have been ahgned and tables showing these ahgnments are available from various published sources, such as, for example, in the article by Hanks and Quinn in Methods of Enzymology 200, 38-62 (1991) or in the PKR Web Site: WWW.sdsc.edu/kinases.

US patent 6,174,993, WO 98/53051 (coιτesρonding to pending US application 08/861,153), WO 00/118895 (corresponding to pending US 09/161,094), US pending application 09/458,491 and US 09/734,520 (all incorporated herein by reference) concern small, previously undisclosed, regions of various protein kinases with a high substrate specificity. Short peptides derived from these regions modulate kinase activities, as determined by the modulation of cellular activity in various in vivo and in vitro models. Without wishing to be bound by theory it is assumed that the short peptides disclosed in these apphcations, which mimic some ofthe catalytic domains ofthe kinase, bind to other cellular components with which the kinase interacted (such as substrates, other kinases, other phosphatases, co-factors, effectors, etc.) and thus either mimic the kinase activity, or alternatively inhibits the interaction of the kinase and the cellular components thus iruiibiting kinase activity.

US 6,174,993 and US application 08/861,153 discloses a domain termed the HJ- loop. The "HJ-loop" referred to herein is found within the kinase domain of protein kinases between the middle of Subdomain LX and the middle of Subdomain X. Because of the high degree of homology found in the subdomains of different protein kinases, the amino acid sequences of the domains of different protein kinases can be ahgned. Thus, the HJ-loop of protein kinases can be defined by reference to the amino acid sequence of a prototypical protein kinase, for example PKA-Cα ,and can be said to correspond to a contiguous sequence of about twenty a ino acid residues found between about amino acid

229 and 248 of PKA-Cα A second definition ofthe HJ loop of protein kinases, which is complementary to the definition provided in the proceeding paragraph, can be made by reference to the secondary structure ofthe kinase domain of protein kinases. The kinase domain of protein kinases has been found to contain at least nine alpha helices, referred to as helix A through helix I, nine beta sheets, referred to as bl through b9 (Tabor et al, Phil. Trans. R. Soc. Lond. B24Q:315 (1993), Mohammadi et al, Cell 86:577 (1996) and Hubbard et al, Nature 222:746 (1994)). The HJ loop is a contiguous sequence of about twenty amino acids beginning within the F helix about five a ino acids residues from the N-terminus of the F helix and extending about five amino acid residues into the G helix. US patent application 09/734,520 discloses a region termed the "A-region". The "A region" referred to herein is found within the kinase domain of PKs in Subdomain HI and Subdomain IV With respect to the amino acid sequence of the prototypical protein kinase PKA-Cα the A region can be said to correspond to a contiguous sequence of about 5 eighteen amino acid residues found between about amino acids 92 and 109 of PKA-Cα. hi some PKs, extra amino acids can be present in this region and the size ofthe A region can, therefore, include more than 18 amino acids in length.

With respect to the secondary structure of protein kinases, the A region is a contiguous sequence of about five to twenty amino acids beginning at the middle of the 10 _αC helix (hereby αC) and ending at the beginning ofthe b4 beta sheet.

US patent application 09/458,491 discloses a region termed B4-B5 region. The

"B4-5 region" referred to herein is found within the kinase domain of PKs in Subdomain

IV and the beginning of Subdomain V With respect to the amino acid sequence of the prototypical protein kinase PKA-Cα, the B4-5 region can be said to correspond to a

15 contiguous sequence representing the amino acid residues found between about amino acids 106 and 114 of PKA-C_α.

In some PKs , extra amino acids might be inserted in this region and the size ofthe B4-5 region can, therefore, include more than 9 amino acids in length.

A second definition of the B4-5 region of a PK, which is complementary to the 20 definition provided in the preceding paragraph, can be made by reference to the three dimensional structure of the kinase domain of PKs. The kinase domain of PKs has been found to contain at least nine alpha helices, referred to as helix A through helix I and nine beta sheets, referred to as bl through b9 (Tabor et al, Phil Trans. R Soc. Lond., B24Ω:315 (1993), Mohammadi et al, Cell, &6:577 (1996) and Hubbard et al, Nature 25 2 2:746 (1994). The B4-5 region is a contiguous sequence of about five to twenty five amino acids beginning at the end ofthe b4 beta sheet and into the b5 beta sheet.

US patent application 09/161,095 discloses a region termed the "aD region". The "aD region" referred to herein is found within the kinase domain of PKs in Subdomain V and the beginning of Subdomain VI. The "oD region" of a PK can be defined by reference to the amino acid sequence of a prototypical protein kinase, for example PKA- Cα and can be said to correspond to a contiguous sequence of about twenty amino acid residues found between about amino acid 120 and 139 of PKA-Cα.

In relation to the secondary structure ofthe kinase domain of PKs, the αD region is a contiguous sequence of about fifteen to forty amino acids beginning at the end ofthe b5 beta sheet and extending through the D helix and the following loop to the begirrriing of helix E.

The three dimensional structure of a number of kinases has bee determined. A classical view of this stmcture is given in Knighton et al, Science 253, 407-414 (1991).

SUMMARY OF THE INVENTION

The present invention is based on the fmding that compounds comprising peptides, which are derived from specific regions of Tie-2, c-kit, ILK, VEGF and GRK kinases, or variants of these peptides, were able to inhibit or stimulate angiogenesis in several different model of angiogenesis both in vivo and in vitro. Without wishing to be bound by theory, it is assumed that the peptide part of the compound, mimics a region of the Tie-2, c-kit, ILK, VEGF and GRK kinases, which region is responsible for interactions with other cellular components such as: the substrates ofthe kinase; phosphatases or other kinases which regulate the level of phosphorylation of these kinases, co-factors, ATP and the like. The peptide part of the compound thus interrupts the interaction ofthe native Tie-2, c-kit, JLK, VEGF and GRK kinases with the other cellular components (for example the interactions ofthe kinase with the substrates of this kinase) and this interruption modulates (increases or decreases) the signal-hansduction associated by the Tie-2, c-kit, JLK, and GRK kinases.

Thus the present invention concerns a method for the modulation of angiogenesis comprising contacting blood vessels with an effective amount of a compound comprising a sequence selected from:

(a) a sequence which is a continuous stretch of at least five amino acids present in a native Tie2, in positions of 1030 to 1052, or a sequence which is a continuous stretch of at least five amino acids present in c-kit in positions 861 to 885; or a continuous stretch of at least five amino acids present in a native JLK in positions of 382 to 407; or a continuous stretch of at least five amino acids present in a native VEGF in positions of 1097 to 1121; continuous stretch of at least five amino acids present in a native GRK in positions of 383 to 406 (all denoted HJ-loop);

(b) a sequence which is a continuous stretch of at least five amino acids present in a native Tie2, in positions of 904 to 923, or a sequence which is a continuous stretch of at least five amino acids present in c-kit in positions 672 to 694; or a continuous stretch of at least five amino acids present in a native LLK in positions of 271 to 290; or a continuous stretch of at least five amino acids present in a native VEGF in positions of 918 to 939; continuous stretch of at least five amino acids present in a native GRK in positions of 271 to 291 ( all denoted αD region);

(c) a sequence which is a continuous stretch of at least five amino acids present in a native Tie2, in positions of 887 to 903, or a sequence which is a continuous stretch of at least five amino acids present in c-kit in positions 655 to 671; or a continuous stretch of at least five amino acids present in a native ILK in positions of 256 to 269; or a continuous stretch of at least five amino acids present in a native VEGF in positions of 900 to 917; continuous stretch of at least five amino acids present in a native GRK in positions of 257 to 271( all denoted B4-B5 region);

(d) a sequence which is a continuous stretch of at least five amino acids present in a native Tie2, in positions of 874 to 891, or a sequence which is a continuous stretch of at least five amino acids present in c-kit in positions 640 to 668; or a continuous stretch of at least five amino acids present in a native LLK in positions of 235 to 258; or a continuous stretch of at least five amino acids present in a native VEGF in positions of 884 to 903; continuous stretch of at least five amino acids present in a native GRK in positions of 239 to 260 (all denoted A-region); (e) a variant of a sequence according to any one of (a) to (d) wherein up to 40% ofthe amino acid ofthe native sequence have been replaced with a naturally or non-naturally occurring amino acid or with a peptidomimetic organic moiety; and/or up to 40% of the amino acids have their side chains chemically modified; and/or up to 20% of the amino acids have been deleted; provided that at least 50% of the amino acids in the parent sequence of (a) to (d) are maintained unaltered in the variant, and provided that the valiant has autoimmune disease improving properties;

(f) a sequence of any one of (a) to (e) wherein at least one ofthe amino acids is replaced by the corresponding D- amino acid;

(g) a sequence of any one of (a) to (f) wherein at least one of the peptidic - backbones has been altered to a non-naturally occurring peptidic backbone;

(h) a sequence being the sequence of any one of (a) to (g) in reverse order; and (i) a combination of two or more ofthe sequences of (a) to (h). Preferably the sequences from C-KIT, VEGF and Tie-2 are from the alpha D region (b) above and its derivatives) and sequences from GRK or ILK are from the HJ-region and its derivatives ((a) above). Where the sequence is derived from alpha D region of c-KIT the subsequence of (b) is from positions 677-689; and where the sequence is derived from the alpha D region of Tie2 the subsequence is from positions 909 to 920

By a most preferred aspect, the above method of regulating angiogenesis- controlling genes may be used for therapeutical purposes, i.e., to prevent, treat, or alleviate at least one of the undesired systems of diseases, disorders or pathological conditions which are manifested by non-normal (over or under) angiogenesis. By one aspect, termed the "pro-angiogenesis aspect" the therapeutical methods is used to increase angiogenesis-, for the purpose of prevention, treatment or alleviation of diseases or conditions wherein a beneficial therapeutical affect may be evident by neovascularization. Examples of such diseases are coronary artery diseases, peripheral artery diseases, endothelial vascular diseases, arteriosclerosis, various processes of wound and tissue healing such as healing of bone, tendon, endothelial lining (such as in ulcers in the stomach or the skin), for improving the success rates of cell transplantation techniques, as well as in reconstructive surgery to help re-estabhsh proper blood circulation to the reconstructed tissue.

According to the pro-angiogenesis aspect the sequence as defined in (a) to (i) above is derived from ILK, and in particular from the HJ-region of LLK (a) above) or a derivative of such a sequence (e) to (i) above. By another aspect termed "anti-angiogenesis aspect" the method of the present invention may be used for the treatment, prevention or alleviation of diseases, conditions and disorders wherein a therapeutical beneficial affect is evident through the inhibition, decrease or the prevention of angiogenesis.

Examples of such diseases are cancer, aged-related macular degeneration (which are many times aggravated by normal neovascularization), diabetic retinopathy

(which are also caused by non normal neovascularization), rheumatoid arthritis, psoriasis, obesity, hemangioma (AIDS related), Kaposi sarcoma, arteriosclerosis, and restenosis.

In particular the anti-angiogenesis aspect is used for the treatment of solid tumors such as for example: carcinoma, sarcoma, adenoma, hepatocellular carcinoma, hepatocellular carcinoma, hepatoblastoma, rhabdomyosarcoma, esophageal carcinoma, thyroid carcinoma, ganglioblastoma, fibrosarcoma, myxosarcoma, liposarcoma, chondrosarcoma, osteogenic sarcoma, chordoma, angiosarcoma, endotheliosarcoma, lymphangiosarcoma, synovioma, Ewing's tumor, leiomyosarcoma, rhabdotheliosarcoma, colon carcinoma, pancreatic cancer, breast cancer, ovarian cancer, prostate cancer, squamous cell carcinoma, basal cell carcinoma, adenocarcinoma ,renal cell carcinoma, hematoma, bile duct carcinoma, melanoma, choriocarcinoma, seminoma, embryonal carcinoma, Wilms' tumor, cervical cancer, testicular tumor, lung carcinoma, small lung carcinoma, bladder carcinoma, epithelial carcinoma, ghoma, astrocytoma, medulloblastoma, craniopharyngioma, ependymoma, pinealoma, retinoblastoma,, multiple myeloma, rectal carcinoma, thyroid cancer, head and neck cancer, brain cancer, cancer of the peripheral nervous system, cancer of the central nervous system, neuroblastoma, cancer of the endometrium, as well as metastasis of all the above

According to the anti-angiogenesis aspect the sequence part ofthe compound is derived from the Tie-2, VEGF or c-kit kinases (and in particular the alpha D region of these kinases or derivatives of that region as defined in (e) to-(i) above), the GRK kinase (in particular the HJ-region of the kinase or derivatives of hat sequence as defined in (e) to (i) above.

The term "modulating" in the context of the "pro-angiogenetic" aspect of the present invention concerns increase in the formation and/or growth rate of new blood vessels, stabilization and/or elongation of existing blood vessels.

.This term concerns in the "anti-angiogenetic aspect" of the present invention decrease in the formation and/or growth rate of new blood vessels, destabihzation and/or retraction of existing blood vessels. The increase/decrease may be only in the presence of the compound of the invention as compared to the angiogenesis in the absence of the compound of the invention (for example in the presence of a control compound). Alternatively the increase/decrease may be a change in the response to an external signal such as stress, presence of a growth factor etc., in the presence of the compound of the invention as compared to the response to the same external signal in the absences of the compound ofthe invention.

The term "compound (comprising sequence)" refers to a compound that includes within any of the sequences of (a) to (i) as defined above. The compound may be composed mainly from amino acid residues, and in that case the amino acid component of the compound should comprise no more than a total of about 55 amino acids. Where the compound is mainly an amino acid compound, it may consist of any one ofthe amino acid sequences of (a) to (h), a combination of two or more, preferably of three most preferably of two, of the sequences of (a) to (h) linked to each other (either directly or via a spacer moiety) to give the combination of (i). The compound may further comprise any one of the amino acids sequences, or combinations as described above (in (a) to (i) above), together with additional amino acids or amino acid sequences. The additional amino acids may be sequences from other regions of the Tie-2, c-kit, LLK, VEGF and GRK kinases, sequences that are present in the kinases in the vicinity ofthe above regions, N-terrninal or C-terminal to the sequences of (a) to (d), or sequences which are not present in the Tie-2, c-kit, ILK, VEGF and GRK kinases but were included in the compound in order to improve various physiological properties such as penetration into cells (sequences that enhance penetration through membranes or barriers); decreased degradation or clearance; decreased repulsion by various cellular pumps, improved immunogenic activities, improvement in various modes of administtation (such as attachment of various sequences which allow penetration through various barriers, blood brain barrier through the gut, etc.); increased specificity, increased affinity, decreased toxicity, and the like. A specific example is the addition of the amino acid Gly or several Gly residues linked in tandem to N-teπriinal ofthe sequence.

The compound may also comprise non-arnino acid moieties, such as for example, and preferably, hydrophobic moieties (various linear, branched cyclic, polycychc or heterocyclic hydrocarbons and hydrocarbon derivatives) attached to the peptides of (a) to (i) to improve penetration through the cells' membranes, various protecting groups, especially where the compound is linear, attached to the compound's terminals to decreased degradation, chemical groups present in the compound to improve penetration or decrease toxic side effects, or various spacers, placed for example, between one or more ofthe above amino acid sequences, so as to spatially position them in a suitable orientation with respect to each other. The compound of the invention may be linear or cyclic, and cyclization may take place by any means known in the art. Where the compound is composed predominantly of amino acids/amino acid sequences, cyclization may N- to C- terminal, N-terminal to side chain and N-terminal to backbone, C-terrrhnal to side chain, C-terminal to backbone, side chain to backbone and side chain to side chain, as well as backbone to backbone cyclization. Cyclization of the compound may also take place through the non-amino acid organic moieties.

The association between the amino acid sequence component ofthe compound and other (non-amino acid) components ofthe compound may be by covalent linking, by non- covalent complexion, for example, by complexion to a hydrophobic polymer, which can be degraded or cleaved, thus producing a compound capable of sustained release; by entrapping the amino acid part of the compound in liposomes or micelles to produce the final compound ofthe invention. The association may be by the entrapment ofthe amino acid sequence within the other component (liposomes, micelles) or the impregnation ofthe armno acid sequence vv thin a polymer to give the final compound ofthe invention.

Preferably the compounds comprise an amino acid sequence of (a) to (i) above in association with (in the meaning. described above) a moiety for transport across cellular membranes.

The term "moiety for transport across cellular membranes" refers to a chemical entity, or a composition of matter (comprising several entities) that causes the transport of members associated (see above) with it through phospholipidic membranes. One example of such moieties are hydrophobic moieties such as linear, branched, cychc, polycyclic or heterocyclic substituted or non-substituted hydrocarbons. Another example of such a moiety are short peptides that cause transport of compounds attached to them into the cell by, gradient derived, active, or facihtated transport. Other examples of other non-peptidic moieties known to be transported through membranes, such as glycosylated steroid derivatives, are well known in the art. Yet another example are moieties that are endocytosed by membranal receptors such as ligands ofthe EGF and tiansferrin receptors. The moiety for the transport across membranes may be a polymer, hposome or micelle containing, entrapping or incorporating the amino acid sequence therein. In the above examples the compound of the invention is the polymer, hposome micelle etc., impregnated with the amino acid sequence.

The term "a sequence which is a continuous stretch of at least 5 amino acids present ... "refers to any continuous stretch of at least 5 amino acids, which are present in a longer amino acid sequence described by reference to the specific positions of Tie-2, c- kit, JLK, VEGF and GRK kinases (see below). For example, if in a c-kit kinase, the positions con^sponding to amino acid residues X to Y of c-kit alpha D region are amino acid residues 672 to 694 of that specific kinase, the continuous stretch of at least 5 amino acids may be from amino acid at position 672 to 676, from 673 to 667, from 674 to 678, from 675 to 679, etc. The continuous sequence may also be of 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 and 20 amino acids, obtained from each of these positions. The term "Tie-2 " refers to Tie2 kinase accession Q02763 in NCBI. The term "c-kit" refers to ρl45 -c kit Accession CAA29548 in NCBI. The term "Z£ " refers to the kinase in accession number P57043 in NCBI

The term "VEGF refers to vascular endothelial growth factor receptor 2 precursor (VEGFR-2) or protein -tyrosine kinase receptor Flk-1) accession P35968 in NCBI. - The term :"GRK" refers to GRK2 accession number NP_001610 in NCBI The term "sequence corresponding to positions ... to ... of Tie-2, c-kit, ILK, VEGF and GRK kinases " refers to a sequence that matches the sequence appearing in the native kinases in specific positions. The positions of the regions of the kinases beginning in a certain position and ending in another position are indicated in the definition (a) to (d) above.

The term "wherein up to 40% of amino acids ofthe native sequence have been replaced with a naturally or non-naturally occurring amino acid or with a peptidomimetic organic moiety" in accordance with the present invention, concerns an amino acid sequence, which shares at least 60% of its amino acid with the native sequence as described in (a), (b), (c) or (d) above, but some ofthe amino acids were replaced either by other naturahy occurring amino acids, (both conservative and non-conservative substitutions), by non-naturally occurring amino acids (both conservative and non- conservative substitutions), or with organic moieties which serve either as true peptidomimetics (i.e., having the same steric and electrochemical properties as the replaced amino acid), or merely serve as spacers in lieu of an amino acid, so as to keep the spatial relations between the amino acid spanning this replaced amino acid. Guidelines for the deterrnination of the replacements and substitutions are given in the detailed description part of the specification. Preferably no more than 30%, 25% or 20%, 15% or 10% ofthe amino acids are replaced.

The term "wherein up to 40% ofthe amino acids have their side chains chemically modified" refers to a variant which has the same type of amino acid residue as in the native sequence, but to its side chain a functional group has been added. For example, the side chain may be phosphorylated, glycosylated, fatty acylated, acylated, iodinated or carboxyacylated. Other examples of chemical substitutions are known in the art and some given below in the "Detailed Description" part of the specification. Preferably no more than 35%, 30%, 25%, 20%, 15% ofthe amino acids are chemically modified

The term "up to 20% of the amino have been deleted^'' refers to an amino acid sequence which maintains at least 80% of its amino acids residues. Preferably no more than 10% ofthe amino acids are deleted and more preferably none ofthe amino acids are deleted. The term "provided that at least 50% ofthe amino acids in the parent protein are maintained unaltered in the variants" the up to 40% substitution, up to 40% chemical modification and up to 20% deletions are combinatorial, i.e., the same variant may have substitutions, chemical modifications and deletions so long as at least 50% of the native amino acids are identical to those ofthe native Tie-2, c-kit, ILK, VEGF and GRK kinases sequences both as regards the amino acid residue and its position. In addition, the properties ofthe parent sequence, in "modulating angiogenesis", have to be present in the variant. Preferably at least 60%, 65%, 70%, 75%, 80%, 85% of the amino acids in the parent sequence are maintained in the variant. It should be noted that at times while the parent (native) sequence may modulated angiogenesis in one direction (increase or decrease) the variant may modulate the angiogenesis in another direction (decrease or increase respectively).

When calculating 40% (or 35, 30, 25, 20%) replacements of 20% (or 10%) deletion from sequences, the number of actual a ino acids should be rounded mathematically, so that 40% of an 11-meτ sequence (4.4) is four amino acids and 40% of a 12-mer sequence (4.8) is five amino acids.

Typically "essential amino acids " are maintained, chemically modified or replaced by conservative substitutions, while non-essential amino acids may be maintained, chemically modified, deleted or replaced by conservative or non-conservative replacements. Generally, essential arnino acids are identified by various Structure- Activity-Relationship (SAR) techniques (for example amino acids that when replaced by - Ala cause loss of activity are considered "essential"), or by using various 3D analysis techniques are replaced by conservative substitution while non-essential amino acids can be deleted or replaced by any type of substitution. Guidelines for the deteimination ofthe deletions, replacements and substitutions are given in the "Detailed Description" part of the specification. - -

The term "region" refers to a sequence in a specific location is the kinases as specified bellow: (a) a sequence which is a continuous stretch of at least five arnino acids present in a native Tie2, in positions of 1030 to 1052, or a sequence which is a continuous stretch of at least five arnino acids present in c- t in positions 861 to 885; or a continuous stretch of at least five a ino acids present in a native LLK in positions of 382 to 407; or a continuous stretch of at least five arnino acids present in a native VEGF in positions of 1097 to 1121; continuous stretch of at least five amino acids present in a native GRK in positions of 383 to 406 (all denoted HJ-loop); (b) a sequence which is a continuous stretch of at least five amino acids present in a native Tie2, in positions of 904 to 923, or a sequence which is a continuous stretch of at least five amino acids present in c-kit in positions

672 to 694; or a continuous stretch of at least five amino acids present in a native ILK in positions of 271 to 290; or a continuous stretch of at least five amino acids present in a native VEGF in positions of 918 to 939; continuous stretch of at least five amino acids present in a native GRK in positions of 271 to 291 ( all denoted αD region);

(c) a sequence which is a continuous stretch of at least five amino acids present in a native Tie2, in positions of 887 to 903, or a sequence which is a continuous stretch of at least five amino acids present in c-kit in positions

655 to 671; or a continuous stretch of at least five amino acids present in a native LLK in positions of 256 to 269; or a continuous stretch of at least five arnino acids - present in a native VEGF in positions of 900 to 917; continuous stretch of at least five arnino acids present in a native GRK in positions of 257 to 271( all denoted B4-B5 region);

(d) a sequence which is a continuous stretch of at least five arnino acids present in a native Tie2, in positions of 874 to 891, or a sequence which is a continuous stretch of at least five arnino acids present in c-kit in positions 640 to 668; or a continuous stretch of at least five amino acids present in a native LLK in positions of 235 to 258; or a continuous stretch of at least five amino acids present in a native VEGF in positions of 884 to 903 ; continuous stretch of at least five amino acids present in a native GRK in positions of 239 to 260 (all denoted A-region).

The term "corresponding D-amino acid" refers to the replacement ofthe naturally occurring L-configuration of the natural amino acid residue by the D-configuration ofthe same residue.

The term "at least one peptidic backbone has been altered to a non-naturally occurring peptidic backbone" means that the bond between the N- of one amino acid residue to the C- ofthe next has been altered to non-naturally occurring bonds for example by reduction (to -CH₂-NH-), alkylation (methylation) on the nitrogen atom, or the bonds have been replaced by non-naturally occurring bonds such as amidic bond, urea bonds, or sulfonamide bond, etheric bond (-CH₂-0-), thioetheric bond (-CH -S-), or to -CS-NH-. The side chain of the residue may be shifted to the backbone nitrogen to obtain N- alkylated-Gly (a peptidoid). The term "in reverse order" refers to the fact that the sequence of (a) to (f) may have the order of the arnino acids as it appears in the native Tie-2, c-kit, ILK, and GRK kinases from N- to the C- direction, or may have the reversed order (as read in the C-to N- direction) for example, if a subsequence of the oD of c-kit DLLNFLRRKRDSF a sequence in a reverse order is FSDRKRRLFNLLD. It has been found that many times sequences having such a reverse order can have the same properties, in small peptides, as the "correct" order, probably due to the fact that the side chains, and not the peptidic backbones are those responsible for interaction with other cellular components.

Particularly preferred, are what is termed "retro i verso" peptides - i.e., peptides that have both a reverse order as explained above, and in addition each and every single one of the amino acids, has been replaced by the non-naturally occurring D- arnino acid counterpart, so that the net end result, as regards the positioning of the side chains, (the combination of reverse order and the change from L to D) is zero change. Such retro- inverso peptides, while having similar binding properties to the native peptide, were found to be resistant to degradation.

The term "therapeutically effective amount" is the quantity of compound which results in an improved clinical outcome as a result of the treatment as compared with a typical clinical outcome in the absence ofthe treatment. An "improved clinical outcome" results in an individual with the disease experiencing fewer symptoms or complications of the disease, including a longer life expectancy, as a result ofthe treatment as well as the prevention of the disease before it occurs. The present invention also concerns methods for obtaining the above compounds which compounds can be used in a method for modulating (increasing or decreasing) angiogenesis. Thus the present invention concerns a method for obtaining a compound for the modulation of angiogenesis the method comprising:

(i) providing a plurality of candidate compounds comprising any one of the sequences of (a) to (i) as defined above; (ii) assaying the candidate compounds obtained in (i) in a test assay and deteiTnining the level of change in the angiogenesis; (iii) selecting those compounds that were able to modulate angiogenesis as compared to the modulation in the same test assay in the absence of the candidate compounds, thereby obtaining compounds capable of modulating angiogenesis. Assays for determining angiogenesis modulating properties will be specified in more detail hereinafter below and in general include modulation of proliferation of endothelial and/or smooth muscle cells,; modulation of sprouting of new blood vessels from whole mounts of aortic- rings; determination of infiltration of new blood vessels into sponges implanted under the skin (sponge assay); determination of formation of new blood vessels as a result of the implantation of a chip in the cornea, (eye assay) , changes in the formation of new blood vessels which were dissected in the limbs of large animals.

It should be appreciated that some of the compounds comprising the sequences of (a) to (i) above, have better angiogenesis modulating properties than others, and the selection of the compounds which have these properties should be done according to the method as indicated above.

Preferably, the determination of the sequence to be included in the compound and having angiogenesis modulating properties should be carried out with the following steps: (i) determining in Tie-2, c-kit, JLK, VEGF and GRK kinases four regions as described in (a) to (d) above (ii) determining a continuous stretch of at least 5 arnino acids of any ofthe four regions of Tie-2, c-kit, ILK, VEGFf and GRK kinases (i) above, that is shorter than the length of the entire region, and can modulate angiogenesis by: synthesizing a plurality of subsequences (optionally partially overlapping subsequences) having a length of 5-10 arnino acids from any of the above four regions; testing those sequences in a test assay for determining modulation angiogenesis , and selecting those sequences that have angiogenesis modulating activities ; (hi) determining in the sequences of (i) or in the sequences selected in (ii) above, essential and non-essential amino acids by: preparing a plurahty of modified sequences wherein in each modified sequence a single and different position in the native sequence has been replaced with a test arnino acid (preferably with Ala residue); testing those modified sequences in a test assay to determine modulation angiogenesis; those amino acids which when replaced caused a significant change in the modulation of angiogenesis being "essential amino acids", and those amino acids which when replaced, did not cause a significant change in the modulation of angiogenesis being "non-essential- mino acids"; (iv) preparing a plurality of compounds comprising sequences selected from: (1) the sequences of (i);

(2) the sequences selected in (ii);

(3) -the sequences of (i) or the selected sequence of (ii), wherein at least one of the essential amino acids has been chemically modified, replaced by a conservatively substituted naturally or non-naturally occurring amino acid, or by a conservative peptidomimetic organic moiety; and/or at least one ofthe non-essential amino acids has been chemicaUy modified, deleted, or substituted (conservatively or non- conservatively) by naturally or non-naturally occurring amino acids or a peptidomimetic; (4) the sequences of (1) to (3) in a reverse order;

(5) the sequence of (4) wherein all the amino acids have been replaced by their D-counterpart residues; said compounds of (iv) being candidate compounds for modulating angiogenesis. The selection of those compounds which are active from among the candidate compounds can be carried out in a suitable test assay as explained above.

The sequence of the Tie-2, c-kit, JLK, VEGF and GRK kinases can be obtained from amino acid sequence databases in accordance with the NCBI entries given above,, respectively, by the indications ofthe positions given in (a) to (d) above, and it is possible to locate the above four regions. Although the sequences of the region are not very long (about 8-40 arnino acids long), it is of course desirable to find a shorter (preferably the shortest) subsequence of at least 5 continuous amino acids present within this full region, and use this shorter sequence in the compound of the invention. Finding this short subsequence is a routine procedure, which can be achieved by several possible manners, such as by synthesizing sequences of 5-10 amino acids long, having partially overlapping, or adjacent sequences, and optionally optimizing the chosen sequence (if rather longer sequences are used such as, for example, sequences having a length of 8-10) by sequentiaHy-deletmg-nOm one or both of its-teιτninals arnino aeids until the optimal shorter sequence (not necessarily the shortest but a combination of length and activity should be considered) still capable of modulating angiogenesis, is obtained.

After obtaining shorter subsequences which still have angiogenesis modulating properties, it is necessary to find which a ino acids, either in the- sequence of the full region but preferably in the sequence ofthe shorter subsequence, are essential (crucial for the angiogenesis modulating activity) and which are non-essential. This can be done by routine Structure-Activity-Relationship (SAR) analysis, wherein a plurahty of sequences . are prepared, wherein in each sequence a single (and different) amino acid has been replaced, as compared to the native sequence by a "test amino acid" - usually the amino acid residue Alanine (a procedure known as: "Ala-scan"). Each of the plurahty of sequences is again tested for its properties in modulating angiogenesis. Amino acids which when replaced cause loss, or substantial decrease in the modulating properties (both in the pro-angiogenesis as well as in the anti-angiogenesis aspects) as compared to the native sequence, are considered as "essential a ino acids ". Arnino acids which when replaced do not cause a decrease modidating properties of the sequence (as compared to the native sequence) are referred to as "non-essential" arnino acids (the loss or decrease should be determined by statistically significant manners).

Finally, as a last step, a plurahty of sequences is prepared which may comprise either the full native sequence of any ofthe regions,; short subsequence of at least 5 a ino acids as appearing in any of the regions; variants of the native sequences wherein at least one essential arnino acid has been replaced by conservative substitution by a naturaUy, non-naturally occurring amino acid or by a peptidomimetic organic moiety or having, been chemically modified; or variants of the native sequence wherein at least one amino acid (present in a non-essential position) has been deleted or chemically modified, or an amino acid in a non-essential position has been replaced by conservative or non-conservative substitution by a naturally occurring, non-naturally occurring, or organic peptidomimetic moiety.

For example, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 arnino acids may be replaced in the sequence used in the compound of the invention as compared with the native sequences present in the Tie-2, c-kit, ILK, VEGF and GRK kinases. The total combination of replacements, deletions, etc. should be such that the resulting variant shares at least 50% ofthe amino acids with the native sequence (both as regards the nature ofthe residue and its position in the sequence).

A notable exception to the above is the use of retro-inverso amino acids (in reverse order as compared to the native sequence), where when the peptide is in the reversed order, all of its arnino acids are replaced with their D- counterparts.

When preparing the compound, it is possible to proceed by one of two strategies: by one strategy it is possible to test (for properties in modulating angiogenesis) a full compound - i.e., a compound comprising both a candidate sequence, and for example, non-amino acid moieties such as hydrophobic moieties present in one of its terminals. This strategy is generally used where the test assay is intact cells, in tissue (ex-vivo) or an in-vivo assays where the penetration through membranes, (solved by addition of a hydrophobic moiety), is crucial.

Alternatively, it is possible to first optimize the sequence alone (preferably by testing it in a cell-free system (for example for testing for Tie-2, c-kit, JLK, VEGF and GRK kinases dependent phosphorylation of substrates) so as to first find the best sequence possible, and then add to the optimal sequence other moieties, such as hydrophobic moieties, etc. to improve other properties of the compound as a whole such as for the purpose of improving the penetration into cells, resistance to degradation, etc. The present invention also concerns compounds for modulation of angiogenesis obtained by any ofthe above methods.

The present invention further concerns pharmaceutical compositions comprising the above compounds as active ingredients. The pharmaceutical composition may contain one species of compounds of the invention or a combination of several species of the invention.

The pharmaceutical compositions of the invention should be used for modulation of angiogenesis. ^• . . ^{. .} _ ^. -

The pharmaceutical compositions in the pro-angiogenesis aspect may be used for the treatment of a disease selected from: coronary artery diseases, peripheral artery diseases, endothelial vascular diseases, arteriosclerosis, various processes of wound and tissue healing such as -healing of bone, tendon, endothelial hαing (such as in ulcers in the stomach), for improving the success rates of cell transplantation techniques, as well as in reconstructive surgery to help re-estabhsh proper blood circulation to the reconstructed tissue.

In the anti-angiogenesis aspects the pharmaceutical compositions may be used for the treatment of a disease selected from: cancer, aged-related macular degeneration (which are many times aggravated by normal neovascularization), diabetic retinopathy (which are also caused by non normal neovascularization), rheumatoid arthritis, psoriasis, obesity, hemangioma (AIDS related), Kaposi sarcoma arteriosclerosis, and restenosis.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to understand the invention and to see how it may be carried out in practice, a preferred embodiment will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

Fig. 1 is a table showing active compounds ofthe invention by the name (peptide), region, sequence and the assay in which they were tested (proliferation of endothelial A19 or HEC or SMC, aortic ring, sponge or eye assay); Fig. 2. shows proliferation results of either endothelial cells (HEC) or smooth muscle cells (SMC) in the presence of compounds comprising c-kit derived peptides (2A), Tie-2 derived peρtides(2B), JLK derived peptides (2C),VEGF derived peptides (2D)

Fig. 3 shows changes in neovascularization in aortic ring assay in the presence of compounds comprising c-kit derived peptides (3A), Tie-2 derived peptides (3B), ILK derived peptides (3 C), VEGF derived peptides (3D) and GRK derived peptides (3E)

Fig. 4. shows whole mount staining of aortic rings for SMC's actine in the presence ofthe compounds ofthe invention:

Fig. 5. shows in vivo results of inhibition of angiogenesis in the sponge assay in the presence of Tie-2 derived peptides.

Fig. 6 shows in vivo results of the stimulation of angiogenesis in the eye in the presence of an JLK-derived peptide. - -

DETAILED DESCRIPTION OF THE INVENTION

1. Addition of non-peptidic groups to produce the compound ofthe invention Where the compound of the invention is linear, it is possible to place in any of its terminal various functional groups. The purpose of such functional groups may be for the increase ofthe angiogenesis modulating properties. The functional groups may also serve for the purpose of improving physiological properties of the compound not related directly to the angiogenesis modulating properties such as: increase the stability, increase the penetration through membranes, optimize the tissue localization of the compound, improve the efficacy, decrease the clearance, decrease the toxicity, improve the selectivity, improve the resistance to repletion by cellular pumps, improve the penetration of the compound through barriers (blood, brain, gut) and the like. For convenience sake the free N-terminal of one of the sequences contained in the compounds of the invention will be termed as the N-terminal of the compound, and the free C-terminal of the sequence will be considered as the C-terminal of the compound (these terms being used for convenience sake). Either the C-termrnus or the N-teiminus of the sequences, or both, can be linked to a carboxylic acid functional groups or an amine functional group, respectively.

Suitable functional groups are described in Green and Wuts, "Protecting Groups in

Organic Synthesis", John Wiley and Sons, Chapters 5 and 7, 1991, the teachings of which are incorporated herein by reference. Preferred protecting groups are those that facihtate transport ofthe compound comprising the group into a cell, for example, by reducing the hydrophihcity and increasing the hpophihcity ofthe compound.

These -moieties- (the functional-groups) can be cleaved in vivo, either by hydrolysis or enzymatically, inside the cell. (Ditter et al, J. Pharm. Sci. 52:783 (1968); Ditter et al., J. Pharm. Sci. 57:828 (1968); Ditter et al., J. Pharm. Sci. 58:557 (1969); King et al, Biochemistry 26:2294 (1987); Lindberg et al, Drug Metabolism and Disposition 12:311 (1989); and Tunek et al, Biochem. Pharm. 22:3867 (1988), Anderson et al, Arch. Biochem. Biophys. 222:538 (1985) and Singhal et al, FASEB J. .1:220 (1987)). Hydroxyl protecting groups include esters, carbonates and carbamate protecting groups. Amine protecting groups include alkoxy and aryloxy carbonyl groups, as described above for N- terminal protecting groups. Carboxylic acid protecting groups include aliphatic, benzylic and aryl esters, as described above for C-terminal protecting groups. In one embodiment, the carboxylic acid group in the side chain of one or more glutamic acid or aspartic acid residue in a compound of the present invention is protected, preferably with a methyl, ethyl, benzyl or substituted benzyl ester, more preferably as a benzyl ester. til addition, a modified lysine residue can be added to the C-terminal of the compound to enhance biological activity. Examples of lysine modification include the addition of an aromatic substitute, such as benzoyl benzoic acid, dansyl-lysrne various derivatives of benzoic acids (difluoro-, trifluromethy-, acetamido-, dimethyl-, dimethylamino-, methoxy-) or various derivatives of carboxylic acid (pyrazine-, thiophene-, pyridine-, indole-, naphthalene-, biphenyl,), or an aliphatic group, such as acyl, or amyristic or stearic acid, at the epsilon amino group ofthe lysine residue.

Examples of N-teiminal protecting groups include acyl groups (-CO-R1) and alkoxy carbonyl or aryloxy carbonyl groups (-CO-0-R1), wherein Rl is an aliphatic, substituted ahphatic, benzyl, substituted benzyl, aromatic or a substituted aromatic group. Specific examples of acyl groups include acetyl, (ethyl)-CO-, n-propyl-CO-, iso-propyl- CO-, n-butyl-CO-, sec-butyl-CO-, t-butyl-CO-, hexyl, lauroyl, palmitoyl, myristoyl, stearyl, oleoyl phenyl-CO-, substituted phenyl-CO-, benzyl-CO- and (substituted benzyl)- CO-. Examples of alkoxy carbonyl and aryloxy. carbonyl groups include CH3-0-CO-, (ethyl)-0-CO-, n-propyl-O-CO-, iso-propyl-O-CO-, n-butyl-O-CO-, sec-buryl-O-CO-, t- butyl-O-CO-, phenyl-O-CO-, substituted phenyl-O-CO- and benzyl-O-CO-, (substituted benzyl)-0-CO-.- - Adamantan,- naphtalen, myristoleyl, tuhien, biphenyl, cinnamoyl, nitrobenzoy, toluoyl, furoyl, benzoyl, cyclohexane, norbornane, Z-caproic. In order to facihtate the N-acylation, one to four glycine residues can be present in the N-terminus of the compound.

The carboxyl group at the C-terrninus of the compound can be protected, for example, by an amide (i.e., the hydroxyl group at the C-terrninus is replaced with -NH 2, -

NHR2 and -NR2R3) or ester (i.e., the hydroxyl group at the C-terminus is replaced with - OR2). 2 and R3 are independently an aliphatic, substituted ahphatic, benzyl, substituted benzyl, aryl or a substituted aryl group, til addition, taken together with the nitrogen atom, R2 and R3 can form a C4 to C8 heterocyclic ring with from about 0-2 additional heteroatoms such as nitrogen, oxygen or sulfur. Examples of suitable heterocyclic rings include piperidinyl, pyirohdinyl, morpholino, thiomorpholino or piperazinyl. Examples of C-terminal protecting groups include -NH2, -NHCH3, -N(CH3)2, -NH(ethyl), -N(ethyl)2 ,

-N(methyl) (ethyl), -NH(benzyl), -N(C1-C4 alkyl)(benzyl), -NH(phenyl), -N(C1-C4 alkyl) (phenyl), -OCH3, -O-(ethyl), -0-(n-propyl), -0-(n-butyl), -0-(iso-propyl), -O-(sec-butyl),

-0-(t-butyl), -O-benzyl and -O-phenyl.

Preferably the compound includes in the N-terminal a hydrocarbon having a length of C4-C20 preferably Cβ-Cis, most preferably 0-C16. Examples of hydrophobic moieties are: merystyl, stearyl, lauroyl, palmitoyl and acetyl etc. 2. Finding the shortest continuous stretch-subsequence ofthe region

As indicated, the sequences from which the continuous stretch of arnino acids are by the following positions :

(a) a sequence which is a continuous stretch of at least five arnino acids present in a native Tie2, in positions of 1030 to 1052, or a sequence which is a continuous stretch of at least five amino acids present in c-ldt in positions 861 to 885; or a continuous stretch of at least five amino acids present in a native ILK- in positions of 382 to 407; or a continuous stretch of at leastfive arnino acids present in a native VEGF in positions of 1097 to 1121; continuous stretch of at least five a ino acids present in a native GRK in positions of 383 to 406 (all denoted HJ-loop);

(b) a sequence which is a continuous stretch of at least five amino acids present in a native Tie2, in positions of 904 to 923, or a sequence which is a continuous stretch of at least five amino acids present in c-kit in positions 672 to 694; or a continuous stretch of at least five arnino acids present in a native ILK in positions of 271 to 290; or a continuous stretch of at least five amino acids present in a native VEGF in positions of 918 to 939; continuous stretch of at least five arnino acids present in a native GRK in positions of 271 to 291( all denoted D region); ^' (c) a sequence which is a continuous stretch of at least five amino acids present in a native Tie2, in positions of 887 to 903, or a sequence which is a continuous stretch of at least five arnino acids present in c-kit in positions 655 to 671; or a continuous stretch of at least five arnino acids present in a native ILK in positions of 256 to 269; or a continuous stretch of at least five arnino acids present in a native VEGF in positions of 900 to 917; continuous stretch of at least five amino acids present in a native GRK in positions of 257 to 271 ( all denoted B4-B5 region);

(d) a sequence which is a continuous stretch of at least five amino acids present in a native Tie2, in positions of 874 to 891, or a sequence which is a continuous stretch of at least five amino acids present in c-kit in positions

640 to 668; or a continuous stretch of at least five amino acids present in a native ILK in positions of 235 to 258; or a continuous stretch of at least five amino acids present in a native VEGF in positions of 884 to 903 ; continuous stretch of at least five amino acids present in a native GRK in positions of 239 to 260 (all denoted A-region).

The continuous stretch of at least five amino acids (preferably the shortest possible sequence) can be found: by preparing^" a series^" of partially overlapping peptides each of 5-

10 amino acids and each obtained by synthesizing a sequence that is one position removed from the previous sequence.

For example, if the HJ region of GRK is in positions 383 406, and it is to be desired to prepare 10 mer peptides, then the following, partially overlapping peptides are prepared, a peptide having the sequence 383-392, 384-394, 397-406. The angiogenesis modulating properties are then determined in a relevant assay as will be explained below in the examples. The best 10-mer peptide is then chosen.

For checking whether the 10 mer peptide can be reduced in length, it is possible to either repeat the above procedure (preparing a series of partially overlapping peptides) using for example 5 mer peptides that span the length ofthe 10 mer peptide, or to shorten the 10 mer peptide by alternately deleting, from each terminal, an amino acid, and testing the angiogenesis modulating properties of the progressively truncated peptides, until the optimal sequence of at least 5, at least 6, at least 7, at least 8, at least 9 mer peptide is obtained, or until verification that longer sequences are required. As the regions are relatively small, the number of different peptides to be tested is also small. For example, for a region αD of c-kit has a length of 23 amino , there is a need to prepare only 15 peptides to find the optimal 8 mer peptide. After the best 8-mer peptide is obtained, it is possible to delete sequentially amino acids from one or both terminals ofthe 8 per peptide for obtaining the shortest sequence of 5, 6 or 7 mer that is still active. For these steps only 19 sequences have to be tested. 3. Identifying essential and non-essential amino acids in the subsequence chosen

A. Ala-Scan

Once the shorter continuous stretch of at least 5 (at least 6, 7, 8, 9, 10, 11 or 12) - amino acids has been identified, as explained above, it is necessary to realize which ofthe amino acids in the stretch are essential (i.e., crucial for angiogenesis modulating activities) and which are non-essential. Without wishing to be bound by theory, in almost every native protein involved- in interaction with other cellular components, some amino acids are involved in the interaction (these being the "essential aπiino acids") and some amino acids are not involved in the interaction ( these being "non-essential amino acids"), for example since they are cryptic. A short peptide which is to mimic a region ofthe Tie-2, c- kit, TLK, yΕGF and GRK kinases behaves in the same way as the region when present in the full kinase: some amino acids actually interact with the substrate (or with the other interacting cellular components) and other amino acids merely serve to spatially position the interacting amino acids, but do not participate in the interaction (binding) with the other cellular components.

Essential amino acids have to be maintained (i.e., be identical to those appearing in the native kinase), chemically modified, or replaced by conservative substitutions (see definition below) to obtain variants of the peptides. Non-essential arnino acids can be maintained, deleted, chemically modified, replaced by a spacer or replaced by conservative or non-conservative substitutions.

Identification of essential vs. non-essential amino acids in the peptide can be achieved by preparing several peptides that have a shorter sequence than the full region (see Example 2 above) in which each amino acid is sequentially replaced by the arnino acid Ala ("Ala-Scan. "), or sequentially each amino acid is omitted 'omission-scan"). This allows to identify the amino acids which angiogenesis modulating properties are decreased by said replacement/omission (these amino acids being defined as "essential") and which are replacements/ omissions do not decrease by modulating properties ("non- essential") (Morrison et al, Chemical Biology 5:302-307, 2001). Another option for testing the importance of various peptides is by the use of site-directed mutagenesis. Other Stracture-Activity-Relationship techniques may also be used.

B. 3D-arm1ysls

Another strategy for finding essential vs. non-essential amino acids is by determining which a ino acids of the regions, in the 3D structure of the full kinase, are exposed and which are cryptic. This can be done using standard software such as SPDB Viewer™, "color by accessibility" of Glaxo-Welcome.

Typically cryptic amino acids are non-essential, and exposed or partially exposed amino acids are more likely to be essential as they are available for interaction with the other cellular components. In addition, if one wishes to "guess" theoretically which "non-conservative" substitutions in the cryptic region can be tolerated, a good guideline is to "check" on a 3D computer model of the full kinase, whether a peptide, superimposed on the full kinase and bearing those changes, still has the overall structure of the region and more importantly, whether the exposed amino acids in the variant (having those substitutions) still overlap the positions of the exposed amino acids in the full kinase. Those non-conservative substitutions, that when simulated on a computer 3D structure (for example using the Tripose™ software) do not cause drastic alterations of the overall shape of the region (i.e., drastic shifting in the positioning of the exposed amino acids) are likely to be non- conservative replacements that can be tolerated, and those substitutions that do cause drastic changes are replacements that are likely to be undesirable.

Thus prior to experimental testing it is possible to reduce the number of tested candidates by computer simulation. Where the 3D structure of a specific kinase is not available in actual crystallography data, it is possible to obtain a "virtual" 3D structure of the kinase based on homology to known crystallographic structures using such progress such as CompSer™ (Tripose, USA). 4. Obtaining Variants

The sequence regions of the compounds of the invention may be the native sequences obtained from the Tie-2, c-kit, ILK, VEGF and GRK kinases (preferably the shortest possible sequence from the regions of the kinases), or alternatively variants of the native sequence obtained by deletion, (of non-essential amino acids) or substitution (only conservative substitutions in essential positions, both conservative and non-conservative of non-essential acids), or by chemical modifications of the side chains.

4.1 Deletions and insertions Deletions can occur, in particular deletions ofthe "non-essential amino acids".

Additions may occur in particular at the N-terminal or the C-terminal of any of the amino acids of the sequence. No more than 20%, preferably 10%, most preferably none of the amino acids should be deleted. Insertions should preferably be N-terminal or C-terminal to the sequence of (a) to (h) or between the several sequences linked to each other in (i). However other insertions or deletions are possible. Again, the feasibility of the deletions in creating a peptide which is a good mimic of the native region (when present in the fall kinase) can be evaluated virtually by reverting to the 3D-model as described above, and finding which deletions (when the variant is superimposed on the 3D structure of the full kinase) still maintain the exposed side chains in the same orientation as in the native region (when present in the full kinase). This is achieved by superimposing the peptide virtually on the kinase, in the relevant region, so as to determine whether deletions changed drastically the spatial orientation ofthe exposed side chains.

4.2 Replacements The variants can be obtained by replacements (termed also in the text

"substitutions") of any of the amino acids as present in the native kinases. As may be appreciated there are positions in the sequence that are more tolerant to substitutions than others, and in fact some substitutions may improve the activity of the native sequence. The determination of the essential vs. non-essential positions may be achieved by using "Ala-Scan," "omission seem" "site directed mutagenesis" (all the above being routine SAR procedures) or 3D theoretical considerations as described in 3 above. Generally speaking the amino acids that were found to be "essential" should either be identical to the amino acids present in the native Tie-2, c-kit, JLK, VEGF and GRK kinases, chemically modified, or alternatively substituted by "conservative substitutions" (see below). The arnino acids which were found to be "non-essentiaf might be identical to those in the native^~peptide, may be substituted by conservative or non-conservative substitutions, may be chemically modified, may be deleted, or replaced by "spacers". The term "naturally occurring amino acid" refers to a moiety found within a peptide and is represented by -NH-CHR-CO-, wherein R is the side chain of a naturally occurring arnino acid. - -

The term "non-naturally occurring amino acid" (amino acid analog) is either a peptidomimetic, or is a D or L residue having the following formula: -NH-CHR-CO-, wherein R is an ahphatic group, a substituted ahphatic group, a benzyl group, a substituted benzyl group, an aromatic group or a substituted aromatic group and wherein R does not correspond to the side chain of a naturally-occurring amino acid. This term also refers to the D-amino acid counterpart of naturally occurring amino acids. Amino acid analogs are well known in the art; a large number of these analogs are commercially available. Many times the use of non-naturally occurring amino acids in the peptide has the advantage that the peptide is more resistant to degradation by enzymes which fail to recognize this configuration of amino acids.

The term "conservative substitution" in the context ofthe present invention refers to the replacement of an amino acid present in the native sequence in the specific kinase with a naturally or non-naturally occurring amino or a peptidomimetics having similar steric properties. Where the side-chain of the native amino acid to be replaced is either polar or hydrophobic, the conservative substitution should be with a naturally occurring arnino acid, a non-naturally occurring amino acid or with a peptidorriimetic moiety which is also polar or hydrophobic (in addition to having the same steric properties as the side- chain ofthe replaced amino acid). However where the native arnino acid to be replaced is charged, the conservative substitution, according to the definition of the invention, may also be with a naturally occurring arnino acid, a non-naturally occurring arnino acid or a peptidomimetic moiety which are charged, or with non-charged (polar, hydrophobic) amino acids that have the same steric properties as the side-chains of the replaced arnino acids. The purpose of such a procedure of ma taining the steric properties but decreasing the charge is to decrease the total charge ofthe compound.

For example in accordance with_ the invention the following substitutions .are considered as conservative: replacement of arginine by cytroline; arginine by glutamine; aspartate by asparagine; glutamate by glutamine.

As the naturally occurring amino acids are grouped according to their properties, conservative substitutions by naturally occurring arnino acids can be easily determined bearing in mind the fact that in accordance with the invention replacement of charged amino acids by sterically similar non-charged arnino acids are considered as conservative substitutions.

For producing conservative substitutions by non-naturally occurring arnino acids it is also possible to use arnino acid analogs (synthetic amino acids) well known in the art. A peptidomimetic of the naturally occuiring amino acid is well documented in the Hterature known to the skilled practitioner. When affecting conservative substitutions the substituting amino acid should have the same or a similar functional group in the side chain as the original amino acid.

The foUowing are some non-limiting examples of groups of naturally occurring arnino acids or of amino acid analogs are listed beUow. Replacement of one member in the group by another member of the group will be considered herein as conservative substitutions:

Group I includes leucine, isoleucine, valine, methionine, phenylalariine, serine, cysteine, threonine and modified amino acids having the following side chains: ethyl, n- butyl, -CH₂CH₂OH, -CH₂CH₂CH₂OH, -CH₂CHOHCH₃ and -CH₂SCH₃. Preferably Group I includes leucine, isoleucine, valine and metMonine. Group II includes glycine, alanine, valine, serine, cysteine, threonine and a modified amino acid having an ethyl side chain. Preferably Group II includes glycine and alanine.

Group HI includes phenylalanine, phenylglycine, tyrosine, tryptophan, cyclohexylmethyl, and modified amino residues having substituted benzyl or phenyl side chains. Preferred substituents include one or more of the following: halogen, methyl, ethyl, nitro, methoxy, ethoxy and -CN. Preferably, Group HI includes phenylalanine, tyrosine andtryptophan. ^{" "}

Group IV includes glutamic acid, aspartic acid, a substituted or unsubstituted ahphatic, aromatic or benzyhc ester of glutamic or aspartic acid (e.g., methyl, ethyl, n- propyl iso-propyl, cyclohexyl, benzyl or substituted benzyl), glutamine, asparagine, CO-

NH-alkylated glutamine or asparagine (e.g., methyl, ethyl, n-propyl and iso-propyl) and modified amino acids having the side chain -(CFLJ_g.COOH, an ester thereof (substituted or unsubstituted ahphatic, aromatic or benzyhc ester), an amide thereof and a substituted or unsubstituted N-alkylated amide thereof. Preferably, Group JV includes glutamic acid, aspartic acid, glutamine, asparagine, methyl aspartate, ethyl aspartate, benzyl aspartate and methyl glutamate, ethyl glutamate and benzyl glutamate.

Group V includes histidine, lysine, arginine, N-rnfroarginine, β-cycloarginine, μ- hydroxyarginine, N-antidmocitruline and 2-am o-4-guanidinobutanoic acid, homologs of lysine, homologs of arginine and ormthine. Preferably, Group V includes Mstidine, lysine, arginine, and ormthine, A homolog of an amino acid includes from 1 to about 3 additional methylene units in the side chain.

Group VI includes serine, threonine, cysteine and modified amino acids having Cl-

C5 straight or branched alkyl side chains substituted with -OH or -SH. Preferably, Group VI includes serine, cysteine or threonine.

In this invention any cysteine in the original sequence or subsequence can be replaced by a homocysteine or other sulmydryl-containing amino acid residue or analog.

Such analogs include lysine or β-arnino alanine, to which a cysteine residue is attached through the secondary amine yielding lysine-epsilon amino cysteine or anine-beta amino cysteine, respectively.

The term "non-conservative substitutions" concerns replacement ofthe amino acids as present in the native ie-2, c-kit, JLK, VEGF and GRK kinases by another naturally or non-naturally occurring amino acid, having different electrochemical and/or steric properties, for example as determined by the fact the replacing amino acid is not in the same group as the replaced amino acid of the native kinase sequence. Those non- conservative" substitutions which . fall under the scope of the "present invention are those^" which still constitute a compound having properties in modulating angiogenesis. Because D-amino acids have hydrogen at a position identical to the glycine hydrogen side-chain, D-amino acids or their analogs can often be substituted for glycine residues, and are a preferred non-conservative substitution.

A "non-conservative substitution" is a substitution in which the substituting amino acid (naturally occurring or modified) has sigmficantly different size, configuration and/or electronic properties compared with the a ino acid being substituted. Thus, the side chain ofthe substituting amino acid can be sigriificantly larger (or smaller) than the side chain of the native amino acid being substituted and/or can have functional groups with significantly different electronic properties than the amino acid being substituted. Examples of non-conservative substitutions of this type include the substitution of phenylalanine or cycohexylmethyl glycine for alanine, isoleucine for glycine, or -NH-CH -[(-CH₂)5-COOH]-CO- for aspartic acid.

Alternatively, a functional group may be added to the side chain, deleted from the side chain, or exchanged with another functional group. Examples of non-conservative substitutions of this type include adding an amine or hydroxyl, carboxyhc acid to the aliphatic side chain of valine, leucine or isoleucine, exchanging the carboxyhc acid in the side chain of aspartic acid or glutamic acid with an amine or deleting the amine group in the side chain of lysine or ornithine. In yet another alternative, the side chain of the substituting amino acid can have significantly different steric and electionic properties from the functional group of the a ino acid being substituted. Examples of such modifications include tryptophan for glycine, lysine for aspartic acid and -(CH2)4COOH for the side chain of serine. These examples are not meant to be limiting.

As indicated above the non-conservative substitutions should be of the "non- essential" amino acids. Preferably, the Tie-2, c-kit, ILK, VEGF and GRK kinases may be substituted by benzylamine groups, by biot ylation. Another substitution is di-iodinization of tyrosine. Gly-residues may be substituted by D-isomers especially D-Lys residues.

"Peptidomimetic organic moiety" can be substituted for -amino- aeid residues in the ^• compounds of this invention both as conservative and as non-conservative substitutions. These peptidomimetic organic moieties either replace amino acid residues of essential and non-essential amino acids or act as spacer groups within the peptides in lieu of deleted amino acids (of non-essential arnino acids). The peptidomimetic organic moieties often have steric, electronic or configurational properties similar to the replaced amino acid and such peptidomimetics are used to replace arnino acids in the essential positions, and are considered conservative substitutions. However such similarities are not necessaiily required. The only restriction on the use of peptidomimetics is that the compounds have angiogenesis modulating properties.

Peptidomimetics are often used to inhibit degradation ofthe peptides by enzymatic or other degradative processes. The peptidornimetics can be produced by organic synthetic techniques. Examples of suitable peptidomimetics include D amino acids ofthe corresponding L amino acids, tetrazol (Zabrocki et al, J. Am. Chem. Soc. 1111:5875-5880 (1988)); isosteres of amide bonds (Jones et al, Tetrahedron Lett. 22: 3853-3856 '(1988));

LL-3-amino-2-propenidone-6-carboxyhc acid (LL-Acp) (Kemp et al, J. Org. Chem. 511:5834-5838 (1985)). Similar analogs are shown in Kenip et al, Tetrahedron Lett. 22:5081-5082 (1988) as well as Kemp et al , Tetrahedron Lett. 22:5057-5060 (1988), Kemp et al, Tetrahedron Lett. 22:4935-4938 (1988) and Kemp et al, J. Org. Chem. 54:109-115 (1987). Other suitable peptidornimetics are shown in Nagai and Sato, Tetrahedron Lett. 26:647-650 (1985); Di Maio et al, J. Chem. Soc. Perkin Trans., 1687 (1985); Kahn et al, Tetrahedron Lett. 20:2317 (1989); Olson et al, J. Am. Chem. Soc. 112:323-333 (1990); Garvey et al, J. Org. Chem 56- (1990). Further suitable peptidornimetics include hydroxy-l,2,3,4-tetiahydroisoqu oline-3-carboxylate (Miyake et al, J. Takeda Res. Labs 42:53-76 (1989)); l,2,3,4-tetiahydro-isoqumoline-3-carboxylate (Kazmierski et al, J. Am. Chem. Soc. 122:2275-2283 (1991)); histidine isoquinolone carboxyhc acid (HJ.C) (Zechel et al, Int. J. Pep. Protein Res. 43 (1991)); (2S, 3S)-methyl- phenylalanine, (2S, 3R)-methyl-phenylalanine, (2R, 3S)-methyl-phenylalanine and (2R, 3R)-methyl-phenylalanine (Kazmierski and Hruby, Tetrahedron Lett. (1991)).

4.3 Chemical Modifications fri the present invention the side arnino acid residues appearing in the native sequence may be chemically modified, i.e., changed by addition of functional groups to the side chain. The modification may bejn the process of synthesis ofthe compound, i.e., during elongation of the amino acid chain in the process of sequential addition of arnino acids, i.e., a chemically modified amino acid is added instead of a naturally occurring one. However, chemical modification of an amino acid when it is present in the compound or sequence ("/^'« situ" modification) is also possible.

The amino acid of any ofthe sequence regions ofthe compound can be chemically modified (in the peptide conceptionally viewed as "chemically modified") by carboxymethylation, acylation, phosphorylation, glycosylation or fatty acylation. Ether bonds can be used to join the serine or threonine hydroxyl to the hydroxyl of a sugar. Amide bonds can be used to join the glutamate or aspartate carboxyl groups to an amino group on a sugar (Garg and Jeanloz, Advances in Carbohydrate Chemistry and Biochemistry, Vol. 43, Academic Press (1985); Kwxz, Ang. Chem. Int. Ed. English 26:294- 308 (1987)). Acetal and ketal bonds can also be formed between amino acids and carbohydrates. Fatty acid acyl derivatives can be made, for example, by free amino group (e.g., lysine) acylation (Toth et al, Peptides: Chemistry, Structure and Biology, Rivier and Marshal, eds., ESCOM Publ., Leiden, 1078-1079 (1990)).

4.4 Cyclization o the compound

The present invention also includes cychc compounds which are cyclic molecules. A "cyclic compound" refers, in one instance, to a compound of the invention in which a ring is formed by the formation of a peptide bond between the nitrogen atom at the N-terminus and the carbonyl carbon at the C-terrninus.

"Cyclized" also refers to the formation of a ring by a covalent bond between the nitrogen at the N-terminus of the compound and the side chain of a suitable amino acid in the sequence present therein, preferably the side chain ofthe C-terminal amino acid. For example, an amide can be formed between the nitrogen atom at the N-terrninus and the carbonyl carbσn i the side^" chain of an^'aspartiVacid or a glutamic^'acid: Alternatively, The ^" compound can be cyclized by foiming a covalent bond between the carbonyl at the C- terminus of the compound and the side chain of a suitable amino acid in the sequence contained therein, preferably the side chain ofthe N-terminal amino acid. For example, an amide can be formed between the carbonyl carbon at the C-terrninus and the -arnino nitrogen atom in the side chain of a lysine or an ormthine. Additionally, the compound can be cyclized by foιτning an ester between the carbonyl carbon at the C-terminus and the hydroxyl oxygen atom in the side chain of a serine or a threonine.

"Cyclized" also refers to forming a ring by a covalent bond between the side chains of two suitable amino acids in the sequence present in the compound, preferably the side chains of the two terminal amino acids. For example, a disulfide can be foi ed between the sulfur atoms in the side chains of two cysteines. Alternatively, an ester can be formed between the carbonyl carbon in the side chain of, for example, a glutamic acid or an aspartic acid, and the oxygen atom in the side chain of, for example, a serine or a threonine. An amide can be formed between the carbonyl carbon in the side chain of, for example, a glutamic acid or an aspartic acid, and the amino nitrogen in the side chain of, for example, a lysinq or an ormthine. In addition, a compound can be cyclized with a linking group between the two termini, between one terminus and the side chain of an amino acid in the compound, or between the side chains to two amino acids in the peptide or peptide derivative. Suitable linking groups are disclosed in Lobl et al, WO 92/00995 and Chiang et al, WO 94/15958, the teachings of which are incorporated into this application by reference. Methods of cyclizdng compounds having peptide sequences are described, for example, in Lobl et al, WO 92/00995, the teachings of which are incorporated herein by reference. Cyclized compounds can be prepared by protecting the side chains ofthe two amino acids to be used in the ring closure with groups that can be selectively removed while all other side-chain protecting groups remain intact. Selective deprotection is best achieved by using orthogonal side-chain protecting groups such as ahyl (OAI) (for the carboxyl group in the side chain of glutamic acid or aspartic acid, for example), allyloxy carbonyl- (Aloe) for me- arnino jαitrogen in the. side chain of -lysine. or ornithine,-for example) or acetamidomethyl (Acm) (for the sulfhydryl of cysteine) protecting groups. OAI and Aloe are easily removed by Pd and Acm is easily removed by iodine treatment.

5. Pharmaceutical compositions and therapeutical methods of treatment

The compound of the present invention can be used as an active ingredient (together with a pharmaceutically acceptable carrier) to produce a pharmaceutical composition. The pharmaceutical composition may comprise one or a mixture of two or more of the compounds of the invention in an acceptable carrier. The pharmaceutical compositions may also comprise other therapeutically effective ingredients.

The pharmaceutical compositions should be used for the treatment of a disease wherein a therapeutically beneficial effect may be evident through the modulation (increase or decrease) of angiogenesis. In the pro-angiogenesis aspect the pharmaceutical compositions may be used for . the treatment of a disease selected from: coronary artery diseases, peripheral artery diseases, endothelial vascular diseases, arteriosclerosis, various processes of wound and tissue healing such as healing of bone, tendon, endothelial lining (such as in ulcers in the stomach or the skin), for improving the success rates of cell transplantation techniques, as well as in reconstructive surgery to help re-estabhsh proper blood circulation to the reconstructed tissue.

The term "therapeutically beneficial effect refers either to the prevention of the disease, to alleviation of at least one undesirable effect of the disease, to lessening of the severity of the disease, to the cure of the disease altogether or to slowing the progression of a disease.

^{" " " "}A "therσpeιιtically^~effeOtive^~cmfount" is the quantity^" Of the compound that results ^"iri an improved clinical outcome as a result ofthe treatment compared with a typical clinical outcome in the absence of the treatment. An "improved clinical outcome" results in the individual with the disease experiencing fewer symptoms or complications ofthe disease, including a longer life expectancy, less pain, longer disease free periods, and decrease of any of the manifestations of the disease, improved well being, as a result ofthe treatment as well as the prevention ofthe disease before it occurs. The amount of compound achriinistered to the individual will depend on the type and severity of the disease and on the characteristics of the individual, such as general health, age, sex, body weight and tolerance to drugs. The skilled artisan will be able to determine appropriate dosages depending on these and other factors. Typically, a therapeutically effective amount of the compound can range from about 1 mg per day to about 1000 mg per day for an adult. Preferably, the dosage ranges from about 1 mg per day to about 100 mg per day.

The compounds of the present invention can be adnrinistered parenterally Parenteral administration can include, for example, systemic administration, such as by intramusculai intravenous, subcutaneous, or intraperitoneal injection. The compounds may also be administered locally For example anti-angiogenesis compounds used to decrease the formation of new blood vessels into the tumor site, may be injected directly into the tumor. Pro-angiogenesis compounds may by aα¹ministered directly to the site of coronary blockage to encourage formation of new blood vessels that bypass the blocked region. The pro-angiogenesis compounds may also be administered to the site of the reconstructive surgery to speed the process of formation of new blood vessels at the site. The compounds of the invention may also be administered topically for example for the treatment of external ulcers in the form of salves, ointments, solutions etc. suitable for topical administration. Compounds which resist proteolysis can be administered orally,

5 for example, in capsules, suspensions or tablets. The compound can also be administered by inhalation or insufflations or via a nasal spray.

The compound can be administered to the individual in conjunction with an

- - acceptable- pharmaceutical -carrier-as part of -a pharmaceutical composition or -treating the diseases discussed above. Suitable pharmaceutical carriers may contain inert ingredients 0 which do not interact with the compounds. Standard pharmaceutical formulation techniques may be employed such as those described in Remington's Pharmaceutical Sciences, Mack Pubhshing Company, Easton, PA. Suitable pharmaceutical carriers for parenteral adnήnistration include, for example, sterile water, physiological saline, bacteriostatic saline (saline containing about 0.9% mg ml benzyl alcohol), phosphate- 5 buffered saline, Hank's solution, Ringer's-lactate and the hke. Methods for encapsulating compositions (such as in a coating of hard gelatin or cyclodextran) are known in the art (Baker, et al, Controlled Release of Biological Active Agents, John Wiley and Sons, 1986). The formation may be also resources for aα'rninistration to bone, or in the form of salve, solution, ointment, etc. for topical administration.

0 6. Preparation ofthe Compounds

Peptide sequences for producing any of the sequences of the compounds of the invention may be synthesized by sohd phase peptide synthesis (e.g., t-BOC or F-MOC) method, by solution phase synthesis, or by other suitable techniques including combinations of the foregoing methods. The t-BOC and F-MOC methods, which are estabhshed and widely used, are described in Merrifield, J. Am. Chem. Soc, £S:2149 (1963); Meienhofer, Hormonal Proteins and Peptides, CH. Li, Ed., Academic Press, 1983, pp. 48-267; and Barany and Merrifield, in The Peptides, E. Gross and J. Meienhofer, Eds., Academic Press, New York, 1980, pp. 3-285. Methods of solid phase peptide synthesis are described in Merrifield, R.B., Science, 222:341 (1986); Carpino, L.A. and Han, G.Y., J. Org Chem., 22:3404 (1972); and Gauspohl, H. et al, Synthesis, 5:315 (1992)). The teachings of these references are incorporated herein by reference.

As indicated above the compounds of the invention may be prepared utilizing various peptidic cyclizing techniques. Methods of cychzing compounds having peptide 5 sequences are described, for example, in Lobl et al, WO 92/00995, the teachings of which are incorporated herein by reference. Cyclized compounds can be prepared by protecting the side chains of the two amino acids to be used in the ring closure with groups that can ^{" " "} be selectively removed^" while^{" "}all ^"other ^"side-chain ^"protecting ^"groups^" remain^" intact.

Selective deprotection is best achieved by using orthogonal side-chain protecting groups 10 such as allyl (OAI) (for the carboxyl group in the side chain of glutamic acid or aspartic acid, for example), allyloxy carbonyl (Aloe) (for the arnino nitrogen in the side chain of lysine or ormthine, for example) or acetamidomethyl (Acm) (for the sulfhydryl of cysteine) protecting groups. OAI and Aloe are easily removed by Pd and Acm is easily removed by iodine treatment. 15 Other modes of cyclization (beyond N- to C- terminal cyclization) may include: N- to backbone cyclization, C- to backbone cyclization, N- to side chain cyclization, C- to side chain cyclization, backbone to side chain cychzation, backbone to backbone cyclization and side chain to side chain cychzation.

7. Determination of angiogenesis modulating properties

20 It should be appreciated that some ofthe compounds that comprise sequences (a) -

(i) above have better properties in modulating angiogenesis than others. Some of the conservative substitutions in the essential positions may diminish the angiogenesis modulating properties, while other such conservative substitution in the essential positions may improve these properties. The same is true also for deletions, substitutions (both 5 conservative and non-conservative) in non-essential positions, as well as to chemical modifications of the side chains (in any position) or insertions. In addition the type and size ofthe non-arnino acid portion ofthe compounds, such as a hydrophobic moiety in one of its terrninals, may diminish or increase the angiogenesis modulating properties. The angiogenesis modulating properties may be determined by using one ofthe assays below. 7.1 Cellular Assay

An indication on the angiogenesis modulating properties may be by the determination of the change of the proliferation of endothelial cells or Smooth Muscle Cells (SMC) (for example using the methylene blue technique): However lack of effect on the proliferation is not conclusive as regards lack of effect on the angiogenesis, as many times angiogenesis is changed even without change in the proliferation ofthe endothelial cells for example by termption/inhibition of the endothelial and/or smooth muscle cell- cell interactions andtherr-arrang-ement in-regular structures. - - —

The activity of the candidate compound is assessed and compared with a suitable control, e.g., the proliferation ofthe same cells incubated under the same conditions in the absence ofthe candidate compound (or in the presence of a control compound). A greater or lesser proliferation_^as compared with the control indicates that the candidate compound modulates endothelial and/or smooth muscle cell proliferation alluding to a possible effect (that has to be verified) on angiogenesis.

7.2 Phosphorylation of substances

It is possible to assess the kinase activity and the changes in this activity as comnared to control bv determining the phosnhorvlation level of the downstream signal transduction pathway members substrate proteins of Tie-2 (PKB, PKC, Dok-R, Nek) or of the c-kit kinase (AKT,PI3K/PKB, Grb2/Sos/Uas/Ua£MEK ERK, Lyn, JAK2, STAT1/5), ILK,(PKB p-ser 473), VEGF (PI3KPKB, p38MAPK, FAK/Paxϋlin, Src, PLCγ/PKC Ra£ EK ERK, eNOS) and GRK (GPCR's). Cells known to express the above kinases are incubated with a candidate compound under condition that modulate the kinase-associated activity. Then the cells are lysed, the protein content of the cells is obtained and separated on a SDS-PAGE. The downstream substrates can be identified by use of suitable molecular weight markers and suitable antibodies. The level of downstream substrates phosphorylation can be determined by using anti-phosphotyrosine antibodies or anti Ser/Thr antibodies, either conjugated to a suitable label or further reacted with a label-bearing antibody (see Fujimoto et al, Immunity, 12:47-57 (2000)). Alternatively phosphorylation may be determined in a cell-free system by mcubating each kinase, its substrate for example as specified above, and candidate compounds, in the presence of ATP under conditions enabling phosphorylation.

The proteins are then subjected to SDS-PAGE, transferred to nitroceUulose followed by i munoblotting by anti-phosphotyrosine antibody. Alternatively it is possible to use [γ - P] ATP and quantify the amount of radioactivity in cooperated in the substrate (See Fujimoto e/ α/., The J. of Immunol. 7088-7094 ( 1999).

7.3. Tissue or in vivo Assays

The following are suitable in vivo or ex vivo modes for angiogenesis: 1) Aortic ring -where sprouting of newly formed blood vessels is tested whole mounts of aortic rings obtained from rats (see bellow)

2) Eye assay -where formation of new blood vessels in the cornea of the animal as a response to an FGF-implanted pellet is determined.

3) Sponge assay - where infiltration of new blood vessels into a sponge implanted s.c. in an experimental animal is determined

4) Regression of pre-formed vasculature in tumors (Benjamin L.E. and

ss I ))

5) Re-estabhshment of circulation in dissected vessels in the limbs of experimental animals

EXPERIMENTAL PROCEDURES: 1. Aortic ring assay:

We used the modification of previously described assay (Nicosia, R.F. and

Ottmetti, A. "Growth of microvessels in serum-free matrix culture of rat aorta." Lab.

Invest. 63:115-122. 1990) for capillary growth ex vivo. The assay is based on the phenomenon of endothehal cells proliferation from freshly prepared aorta placed into collagen matrix gel, that finally formed new capillary system. JJ Collagen extraction.

Collagen solution was prepared by extraction from rat tendons (modification of the described assays - Strom, S.C. and Michalopoulos, G. "Collagen as a substrate for cell growth and differentiation." Methods Enzymol. 82:544-55, 1982). For this purpose, rat tails were taken from SABRA rats that were sacrificed in the lab during the different experiments. The tails are stored frozen at -20°C until the day of extraction. About 15 tails are used to produce 1 liter of collagen.

Rat tails were thawed and a section of skin from proximal end of each tail was removed using bone chppers. Remaining skin was pulled away while keeping the tail intact to reveal the white tendons. Tails were washed with DDW. We used two pairs of artery forceps to dissect out tail tendons. Starting from the tip of the tail, the tail was clamped at its end with the artery forceps and using the other clamp approximately 2-3 cm away from another pair, the tail was bended until the vertebrae break and tendons come loose from the remaining ofthe tail. This procedure was repeated several times toward the distal end of the tail. Tendons were cut, washed twice with PBS and placed into Petri dish with 70% Ethanol for sterilization and dehydration. Remaining blood vessels were removed before sterilization. Petri dish with tendons is placed under UV and ethanol is evaporated during overnight incubation.

Then collagen fibers were weighted and solubihzed in sterile 0.1% solution of Acetic Acid in DDW* (1-2 gr per 0.5 hter). Solution was stirred slowly at 4°C during 48h. Undissolved tendons are then discarded by centrifugation (16,000-20,000g, 30'). Collagen Stock solution is stored at -20°C. Prior to storage, the collagen was assayed using the polymerization reaction described below. The polymer was examined for both viscosity and cleanliness from remaining tendon particles. Too viscous collagen was diluted in acetic acid. Too "dirty" is being centrifuged again, at higher speed.

The collagen matrix gel was obtained by simultaneously raising of pH and ionic strength of collagen solution (Elsdale and Bard, 1972). Working solution for this purpose was prepared by the following proportion: Collagen Stock solution - 7parts, MEMxlO (Mirήmum Essential Medium Eagle concentrated xlO (obtained from

BeitHaemec, cat.01-025-5A)) - lpart, Na Bicarbonate 0.15M solution - 2parts.

1 7. Experimental animal The experiments were carried out on two lines of animals - Sabra and Sprague-

Dawley rats, males of 200-250 gr-body weight (1-2 month old). Rats were acclimated to vivarium for 4-10 days before their use in study protocol. Each group (from 2 to 4) ofthe animals was housed in separate cage and fed food and water ad hbitum.

1 Preparation of aortic rings Aiύmals were sacrificed by decapitation after ether anesthesia. Thoracic aortas were dissected and immediately transferred to a Petri dish with bio-mpm-1. The fibroaddipose tissue and small vessels around aorta was carefully removed under a α^ssecting microscope, 1 mm-long aortic rings were sectioned and extensively (2-3 times) rinsed in bio-mpm-1 containing antibiotics (% cat.) (Nicosia and Ottmetti,1990).

1 ,4 Embedding of aortic rings.

The collagen matrix gel solution (see above) was added to 24-well plate (0.4 ml to each well) and collagen polymerization was allowed for 15 min at 37°C. The aorta rings were transferred to the collagen gel solution (in order to glue them to the bottom layer of the gel) and then placed to the center of each well. In mice, 3 rings are embedded in the same well. After 15 rnin incubation of the plates at 37°C another 0.4 ml ofthe collagen solution was carefully added on the top ofthe ring. After the gel is formed 0.4 ml of Serum-Free Endothelial Growth Medium (Rhenium, cat. 17601-030) or bio-mpm-1 (Beit Haemeq cat# 05-060-1) was added to each well. Rings were incubated in 37°c and 10% C0₂. Medium is replaced every 2-3 days.

1 5 Addition nf Compounds

Compound of the invention were added next day after coUagen gel formation in concentration 10-20 uM. compounds were dissolved for 10 mM stock in 100% DMSO. Dilution in 0.1% BSA in PBS to 400 uM stock were done for each AR experiment de novo. The compounds were re-added to AR during each medium changing till well- developed capillary system in control or experimental wells.

ή Experimental treatment. Fixation: Fixation was carried out by adding of Buffered Formalin 4% (was obtained from BioLab, cat.66554) 1.5ml in each well. An hour later solution was changed to fresh Formalin in order to better fixation (overnight).

Staining: We used Crystal Violett (Gencian Violett) 0.02% in Ethanol Abs. as staining solution (1ml for each well overnight at room temperature). After staining, wells were washed massively with 0.02% Sodium Azide water solution during two or three days till transparent matrix.

1 7 Analysis of results

Digital pictures were analyzed using hnagePro software. The total capillary length of at least 6 AR was measured. Dividing the total capillary length to AD diameter normalized the data.

2. Eye assay.

We used a modification of the assay previously described in "A model of angiogenesis in the mouse cornea." B.M. Kenyon, E.E. Voest, C.C. Chen, E. Flynn, J. Folkman and R.J. D'Amato Investigative Ophtalmology & Visual Science, July 1996, Vol. 37, No.8 1625-1632 . The assay is based on the phenomena of formation of new blood vessels in the cornea of mice in response to the implantation in the cornea of a pellet impregnated with FGF.

2J FGF pellets preparation

1. Weight Out: - 120 mg hydron into sterile screwcup - 10 mg sterile sucralfate into Eppendorf

2. Add 1 ml 100% ethyl alcohol to hydron. Vortex till clear (few minutes). 3. Add 20 ng/20 μl bFGF to sucralfate- vortex, spidvac for 5 min (more if needed).

4. Add - 10 μl hydron solution to sucralfate pellet.

5. Mix with sterile spatula. 6. . Using spatula, remove nuxture from tube and smear into nylon square (very quick).

7. Coat each side with hydron - light coat.

8. Stand it on dish to dry - glue the mesh with tape to the bottom and to the wall ofthe plate - pellets must stay in the air (using bacteriological 100 mm plates - less charged).

9. Dιytfflfrrm - 30 min

10. - Store at -20°C till implantation procedure.

11. Pull trends releasing pellets.

12. Choose the pellets with the same size- the white pellets are the FGF containing, the transparent ones are hydron only.

2.2 Materials:

2. Sucralfate - sucrose octasulfate - aluminium complex Sigma cat# S-0652

3. Hydron - soluble poly-2-hydroxyethyhnethacrylate cat# - 97001 4. Mesh - Sefar America Kansas city, MO 64119 - 3120 Cat# 03-300/51,40 inches wide

Solution for FGF and peptides (solution SY

- 20 mM sodium citrate

- lmM EDTA - 9% sucrose

- pH 5.0 7. 3 Pepti de an ή pepti d e + FGF pell ets preparati on

1. To prepare:

- Hydron concentrated stock solution (120 mg/ml in ethanol Abs.)

- Hydron diluted stock solution (60 mg/ml in ethanol Abs.) - sucralfate stock solution (500 mg/ml in solution S sterile !).

- 10 mg peptide.

2. Add 30 μl of solution S to peptide (or 10 μl of solution S and 20 μl of FGF).

3. Add 20 μl of sucralfate stock solution - vortex, speedvac for 5 min (more if needed). 4. Add - 20 μl hydron diluted stock solution to sucralfate + FGF -rpeptide peUet.

5. Mix with sterile spatula.

6. Using spatula, remove mixture from tube and smear into nylon square (very quick). 7. Coat each side with hydron concentrated solution - light coat.

9. Drytiu frrm - 30 in. 10. Store at -20°C till implantation procedure.

11. Pull trends releasing pellets.

2A Implantation procedure. Mice were anesthetized with Ketamin/Rompun Solution (for dosage and solutions preparation see standard anesthetic procedure). The eye is topicaUy anesthetized with Localin (Benoxynate HCI 0.4%, Dr.Fisher, Pharmaceutical Labs. P.O.B. 39071, Tel-Aviv 61390). Using a binocular microscope, a central intι-astromal linear keratotomy is performed with a surgical blade parallel to the insertion of the lateral rectus muscle. Approximate length of the cut is 0.5-0.6 mm length. The globe is proptosed with a forceps. A lameUar micropocket is dissected toward the temporal limbus using the modified von Graefe knife 2x30 mm. AU foUowing procedures must be done without proptosis. A peUet is placed on the corneal surface in the base ofthe pocket and advanced to the temporal end ofthe pocket with one arm ofthe forceps. The distance between pellet and limbal vessel is measured. For FGF containing peUets, the pocket must be extended within 1 mm of the temporal limbus. Antibiotic and antimycotic ointment are apphed to the operated eye to prevent infection and additional irritation ofthe cornea.

2 5 Experimental procedure Measurements were done at 5^t and 7 days after implantation, fri the case of high stimulation inspections were done twice a week till full degradation. The maximum vessel length of neovascularization zone, extending from the limbal vessel toward the peUet was measured. The econtiguous chcurnferential zone of neovascularization was measured as ' clock hours (where 30° are equals 1 clock hour.) 3. Air sac model ('sponge assay").

We used the modification of previously described assays (JLichtenberg, C.A..Hancen et al. "The rat subcutaneous Air Sac Model: a new and simple method for in vivo screening of angiogenesis." Pharmacology and Toxicology 1997. 81, 280-284, A.P. Lage and S.P. Andrade "Assessment of angiogenesis and tumor growth in conscious mice by a fluorometric method." ).

3 1 Experimental animals.

The experiments were done at BalbC mice, males of 6-7 week age. Mice were acclimated to vivarium for four days before then use in study protocol. Each group

(from 8 to 10) of the animals was housed in separate cage and fed food and water ad libitum. The animals were observed daily for clinical signs and body weights were recorded twice weekly. 3 7. Tmplant

Sponge pieces was used for subcutaneous implantation. The sponges were sterilized by autoclaving at 121°C for 15 min. The cellulose sponge SpontexR

(manufactured by Spontex S.A., Beauvais, France) has previously been used in an in vivo experiments for the study of cartilage degradation (Bishop et al. "A novel model of cartilage segregation." J.Pharmacol.Toxicol.Meth. 1993, 30, 19-25.).

3_-3 Air sac formation

4-5 ml of air were introduced dorsally by subcutaneous injection using a 27 gauge needle to produce an air sac located in the middle of the back. The air sacs were re-inflated every forth day. The wall ofthe air sac became progressively thicker with time, and after approximately 10 days a sufficient lining of cells had been established. The implantation of the sponge was made not sooner than 10 days after induction of air sac.

3 4 Implantation technique All mice received intraperitoneal injection of anesthetic solution 0.1 ml per animal before implantation. Solution was prepared at the day of the treatment as followed: 0.85 ml of Ketamin 100 mg/ml (was obtained from Fort Dodge, NDS 0856- 2013-01), 0.15 ml of Rampun 2% (Xylazine HCI 10% , obtained from "Bar-Han", B- 8049), 1 ml PBS. After injection animals was shaved, marked and separate to the groups.

Each animal was placed on its abdomen and the skin of the back was washed with Ethanol 70%. A 0.5-0.7 cm incision was made through the skin covering the air sac. Blunt dissection was used to open a 1 cm deep cavity towards the cranial base of the air sac by careful separation of the skin from the membrane. A sponge implant (0.5 x 0.5 x 0.2 cm) was carefully inserted to. the pocket on the membrane away from the incision. The incision was closed by 2-3 sutures using DexonR 3-0. 3.5 Angiogenic response

The animals were sacrificed by ether aspiration. The overlying skin was carefully removed to expose the transparent membrane and not to rupture the air sac. The extent vascular proliferation was scored in situ. The subjective scoring was taken 5 by foUowing criteria:

0 transparent membrane without vascularization (blank membranes without implant).

1 + slight background vascularization. 2+ few vessels reach the sponge.

10 3+ many vessels reach the sponge with beginning of penetration in the implant. 4+ very intensive formation of the new vessels with reach and penetration of implant. After in situ scoring the implant from each animal was cut into two equal 15 portions. The first portion was placed in the plastic vial contaming 4% Buffered Formalin (for histological sections and further microscopical examination), the second one was measured for hemoglobin concentration

ά. Proliferation assay.

Endothehal cells (HEC) or Smooth muscle ceUs (SMC) were obtained from ATCC. 20 These ceU lines were grown in RPMI 1640 medium supplemented with peniciUin (100 U/ml), streptomycin (100 μg/ml), glutamine (2 mM) and 10% endotoxin free bovine ceU serum (Hyclone).

A suspension of the ceUs at 2xl0⁴ ceUs/ml was prepared in the above-described culture mediums and distributed 0.180 ml per well (about 4000 ceUs/weU) in the weUs of 25 96 weU, flat bottom, tissue culture microtiter plates.

A series of compounds stock solutions were prepared by chlutihg a 10 mM solution ofthe compound in 100% DMSO with phosphate buffered saline (PBS) containing 0.1% bovine serum albumin (BSA) to a concentration of 400 μM. These solutions were labeled DMSO. In many instances, 40 μl ofthe 10 compound in DMSO solution was mixed with 160 μl of 2M NFLHCOs and heated for 40 minutes at 100°C. The resultant solution was then diluted to 400 μM in PBS containing 0.1% BSA. These compounds stock solutions were labeled "tbi". The concentration of compound in each stock solution was adjusted to nine times the desired concentration ofthe compound in the assay mixture. 0.020 ml of each compound stock solution was added to the corresponding weUs about 2 hours after ceU addition, with six replicates for each concentration. In addition, PBS containing 0.1% BSA solution with no added compound was used as a control. The plates were incubated for 72-80 hours at 37°C in a 10% C0₂ humidified incubator. This formulation was termed "tbi", and served as a vehicle and as control. .The plates were labeled and the medium discarded. The weUs were fixed with 4% formaldehyde PBS (PBS buffered with 10% foimahn from Fisher Scientific; Catalog No. HC200-1) ( 0.2 ml/weU) for at least 30 minutes. The weUs were washed one time with borate buffer (0.2 ml/wen) (0.1M, pH 8.5). Freshly filtered 1% methylene blue solution (0.60 ml/weU) was then added to the weUs and incubated for 10 minutes at room temperature. The weUs were then washed five times with tap water, after which the weUs were dried completely. 0.20 ml weU of 0.1 N HCI was added to extract the color. After overnight extraction, the O.D. was read at 630 nm to determine the number of ceUs per well. The procedure for counting ceUs is described in greater detail in Oliver et al. J. Cell Sci., 92: 513 (1989), the teachings of which are incorporated herein by reference.

Whole mnimt staining o the aortic rings.

For whole mount Smooth Muscle Actin (SMA) FITC staining:

1. Fixation with 1 % paraformaldehyde for 30 min.

2. Rinsing with PBS overnight.

3. Block with PBS + 1% BSA overnight + tritonX 100 0.01%.

4. Incubate with rat anti-mouse CD31 (BD PharMingen Catalogue 0195 ID, rat monoclonal anit-pecam, clone MEC13.3.) 1 :500 dilution overnight.

5. Wash with PBS X 3 times. Time over 8-10 hrs. ABCAM mouse monoclonal to alpha actin (SMA) (FITC) Clone 1A4 ab8211- 100 lot: 8393 ABCAM Ltd, Cambridge.

Example 1: Modulation of smooth muscle cell and endothelial cell proliferation by the compounds of the invention. The assay was performed as described above in "Experimental Procedures".

SMC, or endothehal cells (HEC) were incubated with varying concentrations of the compounds of the invention for 4 days, and than were fixated and stained with methylene blue. OD was quantified using an Elisa Reader .to give an indication ofthe number of cells as compared to control. The results are shown in Fig. 2A (for compounds comprising c-kit derived peptides), 2B (for compounds comprising Tie-2 derived peptides), and 2C (for compounds comprising ILK derived peptides), 2D (for compound containing VEGF derived peptides) and. As can be seen c-kit and Tie-2, and VEGF derived peptides inhibited SMC or SMC endothelial cell proliferation, respectively, in a dose dependent manner while compounds comprising ILK derived peptide stimulated cellular proliferation in a dose dependent manner.

Example 2: Modulation of angiogenesis in Aortic ring assay by the compounds of the invention

Aortic ring assay was performed as described above in "Experimental Procedures" with compounds comprising the peptides of the invention. The results of all compounds tested are shown in a table of Fig. 3.

Fig. 3 shows pictures of aortic rings incubated with and without 10 uM of a compound comprising c-kit derived peptide (Fig. 3A), with varying concentrations of compounds comprising Tie-2 derived peptides (Fig. 3B), with and without 10 μM of a compound comprising GRK derived peptide. (Fig. 4E), and with and without 10 μM of a compound comprising ILK derived peptide (Fig. 3C) and with and without VEGF derived peptide (Fig. 3D). As can be seen compounds comprising c-kit, GRK, and Tie-2 and VEGF derived peptides inhibited angiogenesis of aortic rings, while compounds comprising ILK derived peptides stimulated angiogenesis.

Example 3:

Example 4: In vivo model modulation of angiogenesis in a sponge assay, by the compounds of the invention

Air-sac assay was performed as described in "Experimental Procedures" .

Sponges soaked with 20-50 ul of peptide stock solution (400 uM 0.1% BSA 4%

DMSO in PBS) were implanted s.c for two weeks, and than removed and stained for hemoglobin by H&E staining. The results are shown in Fig. 5 for sponges containing compound with Tie-2 derived peptides.

As can be seen the sponge containing the Tie-2 derived peptides features a significantly lower number of penetrated blood vessels as compared to control, mώ^ating that a compound comprising a Tie-2 derived peptides was able to inhibit angiogenesis in an in vivo model.

HΛι:iJlι ι —'. Jt/~ v i r'u aiuuuiuuuii υi ngiugni ow in mi. ^c J *- V uic vuiajjuuiiu- ui ulv. invention.

The eye assay was performed as detailed in "Experimental Procedures", wherein in one eye of the mice a pellet with FGF only was implanted while in the other eye a pellet with a compound comprising an ILK derived peptide was used.

The results are shown in Fig. 6 wherein in Fig. 6A the picture is ofthe eye after 5 days of implantation of the FGF-containing pellet, Fig. 6B is the same eye after 15 days, and Fig. 6C is a picture of the eye implanted with FGF containing chip and administered with an ILK-derived peptide. As can be seen in the FGF-containing implanted pellet after 5 days there was a significant formation of blood vessels (Fig. 6A) that were retracted, and almost disappeared on day 15 (Fig. 6B). Against this the eye administered also with an ILK- derived peptides maintained the vasculature also on day 12 (Fig. 6C). This results indicating that the compound of the invention is capable of modulating angiogenesis by stabilizing newly formed blood vessels for longer periods of time as compared to control.

Claims

CLAIMS:

1. A method for the modulation of angiogenesis comprising contacting blood vessels with an effective amount of a compound comprising a sequence selected from:

(a) a sequence which is a continuous stretch of at least five a ino acids present in a native Tie2, in positions of 1030 to 1052, or a sequence which is a continuous stretch of at least five arnino acids present in c-kit in positions 861 to 885; or a continuous stretch of at least five amino acids present in a native ELK in positions of 382 to 407; or a continuous stretch of at least five . amino acids present in a native VEGF in positions of 1097 to 1121; continuous stretch of at least five amino acids present in a native GRK in positions of 383 to 406 (all denoted HJ-loop);

(b) a sequence which is a continuous stretch of at least five amino acids present in a native Tie2, in positions of 904 to 923, or a sequence which is a continuous stretch of at least five arnino acids present in c-kit in positions 672 to 694; or a continuous stretch of at least five amino acids present in a

- native LLK in positions of 271 to 290; or a continuous stretch of at least five amino acids present in a native VEGF in positions of 918 to 939; continuous stretch of at least five arnino acids present in a native GRK in positions of 271 to 291 ( aU denoted ocD region); (c) a sequence which is a continuous stretch of at least five amino acids present in a native Tie2, in positions of 887 to 903, or a sequence which is a continuous stretch of at least five arnino acids present in c-kit in positions

655 to 671; or a continuous stretch of at least five arnino acids present in a native JLK in positions of 256 to 269; or a continuous stretch of at least five amino acids present in a native VEGF in positions of 900 to 917; continuous stretch of at least five amino acids present in a native GRK in positions of 257 to 271( aU denoted B4-B5 region); (d) a sequence which is a continuous stretch of at least five amino acids present in a native Tie2, in positions of 874 to 891, or a sequence which is a continuous stretch of at least five amino acids present in c-kit in positions 640 to 668; or a continuous stretch of at least five amino acids present in a native JLK in positions of 235 to 258; or a continuous stretch of at least five amino acids present in a native VEGF in positions of 884 to 903 ; continuous stretch of at least five amino acids present in a native GRK in positions of 239 to 260 (aU denoted A-region); (e) a variant of a sequence according to any one (a) to (d) wherein up to 40% of the arnino acid ofthe native sequence have been replaced with a naturally or non-naturally occuning arnino acid or with a peptidomimetic organic moiety; and/or up to 40% of the amino acids have their side chains chemically modified; and/or up to 20% of the amino acids have been deleted; provided that at least 50% of the arnino acids in the parent sequence of (a) to (d) are maintained unaltered in the variant, and provided that the variant has autoimmune disease improving properties; (f) a sequence of any one of (a) to (e) wherein at least one ofthe amino acids is replaced by the corresponding D- amino acid; (g) a sequence of any one of (a) to (f) wherein at least one of the peptidic backbones has been altered to a non-naturaUy occurring peptidic backbone; (h) a sequence being the sequence of any one of (a) to (g) in reverse order; and (i) a combination of two or more ofthe sequences of (a) to (h).

2. A method according to Claim 1, wherein the sequence is selected from:

(i) a sequence which is a continuous stretch of at least five arrrino acids selected from: a sequence present in native c-Kit in position 672-694-of the kinase , a sequence present in Tie2 in positions 904-923 of the kinase, a sequence present in VEGF in positions 918-939 ofthe kinase (αD region) a sequence present in LLK in positions 382-407 ofthe kinase; and a sequence present in GRK2 in positions 383-406 ofthe kinase (HJ-loop); (ii) a variant of a sequence according to (i) wherein up to 40% of the arnino acid of the native sequence have been replaced with a naturaUy or non- naturally occurring amino acid or with a peptidoπrimetic organic moiety; and/or up to 40% of the aniino acids have their side chains chemicaUy modified; and/or up to 20% ofthe amino acids have been deleted; provided that at least 50% of the amino acids in the parent sequence of (i) are maintained unaltered in the variant, and provided that the variant has autoimmune disease improving properties ; (hi) a sequence of any one of (i) or (ii) wherein at least one ofthe amino acids is replaced by the corresponding D- arnino acid; (i ) a sequence of any one of (i) to (iii) wherein at least one of the peptidic backbones has been altered to a non-naturaUy occurring peptidic backbone;

(v) a sequence being the sequence of any one of (i) to (iv) in reverse order; and - a combination of two or more ofthe sequences of (i) to (v).

3. A method according to Claim 2, wherein the position of (I) are positions 926 to 937 of VEGF, 909-920 of Tie-2 or 677-689 of c-kit (sub-sequences of alpha D region).

4. A method according to Claim 1 for the increase of angiogenesis, wherein the sequence is selected from:

(i) a sequence which is a continuous stretch of at least five arnino acids present in the native ELK kinase in positions 382-407(HJ-loop); (ii) a variant of a sequence according to any one of (i) wherein up to 40% ofthe amino acid of the native sequence have been replaced with a naturaUy or non-naturally occurring arnino acid or with a peptidomimetic organic moiety; and/or up to 40% of the amino acids have their side chains chemicaUy modified; and/or up to 20% of the arnino acids have been deleted; provided that at least 50% of the amino acids in the parent sequence of (i) are maintained unaltered in the variant, and provided that the variant has autoimmune disease improving properties; (iii) a sequence of any one of (i) or (ii) wherein at least one ofthe amino acids is replaced by the corcesponding D- amino acid; (iv) a sequence of any one of (i) to (hi) wherein at least one of the peptidic backbones has been altered to a non-naturaUy occurring peptidic backbone; (v) a sequence being the sequence of any one of (i) to (iv) in reverse order; and (vi) a combination of two or more ofthe sequences of (i) to (v).

5. A method according to Claim 4 wherein the increase angiogenesis is for the treatment of a disease selected from; coronary artery diseases, peripheral artery diseases, endothehal vascular diseases, arteriosclerosis, various processes of wound and tissue healing such as healing of bone, tendon, endothelial lining (such as in ulcers in the stomach), for improving the success rates of cell transplantation techniques, as weU as in reconstructive surgery to help re-estabhsh proper blood circulation to the reconstructed tissue.

6. A method according to Claim 1 for the decrease of angiogenesis wherein the sequence is selected from:

(i) a sequence which is a continuous stretch of at least five amino acids present in the native Tie-2 kinase in positions 904-923, a sequence which is continuous stretch of at least five amino acids present in the native c-kit kinase in positions 672-694, a sequence which is a continuous stretch of at least five arnino acids present in the native VEGF kinase in positions 918- 939 (alpha D region); a sequence a continuous stretch of at least five amino acids present in the native GRK kinase in positions 383-406 (HJ-loop);

(ii) a variant of a sequence according to any one of (i) wherein up to 40% ofthe amino acid of the native sequence have been replaced with a naturaUy or non-naturally occurring arnino acid or with a peptidomimetic organic moiety; and/or up to 40% of the amino acids have their side chains chemicaUy modified; and/or up to 20% of the amino acids have been deleted; provided that at least 50% of the amino acids in the parent sequence of (i) are maintained unaltered in the variant, and provided that the variant has autoimmune disease improving properties; (iii) a sequence of any one of (i) or (ii) wherein at least one ofthe amino acids is replaced by the corresponding D- amino acid; (iv) a sequence of any one of (i) to (hi) wherein at least one of the peptidic backbones has been altered to a non-naturaUy occurring peptidic backbone; (v) a sequence being the sequence of any one of (i) to (iv) in reverse order; and

(vi) a combination of two or more ofthe sequences of (i) to (v).

7. A method according to claim 6 wherein the decrease ofthe angiogenesis is used for the treatment of a disease selected from: : cancer, aged-related macular degeneration (which are many times aggravated by normal neovascularization), diabetic ret opathy^' (which are also caused by non normal neovascularization), rheumatoid arthritis, psoriasis, obesity, hemangioma (AIDS related), Kaposi sarcoma arteriosclerosis, and restenosis.

8. A method according to claim 7 wherein the cancer is solid tumor.

9. A method according to claim 8 wherein the solid tumor is selected from: carcinoma, sarcoma, adenoma, hepatoceUular carcinoma, hepatoceUular carcinoma, hepatoblastoma, rhabdomyosarcoma, esophageal carcinoma, thyroid carcinoma, ganglioblastoma, fibrosarcoma, myxosarcoma, liposarcoma, chondrosarcoma, osteogenic sarcoma, chordoma, angiosarcoma, endotheliosarcoma, lymphangiosarcoma, synovioma, Ewing's tumor, leiomyosarcoma, rhabdotheliosarcoma, colon carcinoma, pancreatic cancer, breast cancer, ovarian cancer, prostate cancer, squamous cell carcinoma, basal ceU carcinoma, adenocarcinoma ,renal cell carcinoma, hematoma, bhe duct carcinoma, melanoma, choriocarcinoma, seminoma, embryonal carcinoma, Wilms' tumor, cervical cancer, testicular tumor, lung carcinoma, smaU lung carcinoma, bladder carcinoma, epithelial carcinoma, ghoma, astrocytoma, meduUoblastoma, craniopharyngioma, ependymoma, pinealoma, retinoblastoma,, multiple myeloma, rectal carcinoma, thyroid cancer, head and heck cancer, brain cancer, cancer of the peripherals nervous system, cancer of the central nervous system, neuroblastoma, cancer of the endometrium, as weU as metastasis of aU the above.

10. A method according to claim 1 wherein the compound comprises a sequence depicted in Fig. 1

11. A method according to Claim 1 , wherein the compound is linear.

12. A method according to Claim 11, wherein the compound comprises a hydrophobic moiety at one of its terminals.

13. A method according to Claim 12, wherein the hydrophobic moiety is a hydrocarbon having 4 to 20 carbon atoms.

14. A method according to Claim 12, wherein the compound comprises the hydrophobic moiety conjugated to the N-terminal of any one ofthe sequences as defined in Claim 1(a) to l(i).

15. A method according to Claim 1, wherein the compound is a hydrophobic moiety conjugated to the N-terminal of any one ofthe sequences as defined in Claim 1(a) to l(i).

16. A method according to Claim 11, wherein the compound comprises a hydrophobic moiety conjugated to Gly, present at the N-teπninal of any one ofthe sequences as defined in Claim 1(a) to l(i).