The anti-tumor activity of Cucurmosin and application thereof
Technical field
The present invention relates to biochemical field, particularly relate to the anti-tumor activity and the application thereof of a kind of ribosome inactivating protein in the biological chemistry.
Background technology
In this article, anti-tumor protein is defined as having at least the protein of one of following activity: suppress the human tumor cell line activity, suppress mouse tumor cell line activity.Activity comprises the antagonistic effect of certain limit, and for example part suppresses or causes death.This albumen is protein oligomerization or single chain polypeptide.
The ribosome inactivating protein that from higher plant, extracts (Ribosome-Inactivating Protein, be called for short: RIP), RIP is the rrna inactivation that a class can make eukaryotic cells, thereby suppress intracellular protein synthetic cytotoxin, its mechanism of action is to have RNA N-Glycosylase or be polynucleotide adenosine Glycosylase [EC3.2.2.22] activity.According to its molecular structure, can be divided into 3 classes, Class1 RIP is the single chain polypeptide albumen of tool RNA N-glycosidase activity, for example, Trichosanthin (Trichosanthin from cucurbitaceous plant Snakegourd Fruit piece root, be called for short: TCS), the α of balsam pear seed, β-Semen Momordicae Charantiae albumen (α, β-Momorcharin, be called for short: α, (Pepocin is called for short: PEP) for the β-MOM) and the summer squash albumen of french gourd melon wooden dipper.Type 2 RIP are two peptide catenins, for example, from the abrin (Abrin) of euphorbia plant Ricin (Ricin) and leguminous plants acacia rachii seed, it is to have the A chain of RNA N-glycosidase activity and the B chain of a tool activity of lectin is formed by connecting by disulfide linkage by one.Type 3 RIP are a class jasmone inductive albumen (jasmonate-induced protein), and it is made up of the C end structure territory of a N end structure territory with RNA N-Glycosylase function and a unknown function, for example from the JIP60 of barley.The Class1 RIP that separates from cucurbitaceous plant, for example Trichosanthin, Semen Momordicae Charantiae albumen, sponge gourd albumen, white bryony albumen etc. all have the anti-tumor virus activity, particularly the anti-AIDS cytotoxic activity.About Class1 RIP and existing a lot of patent and the bibliographical informations of type 2 RIP.
Chinese patent 99102290.4 provides isolated Class1 RIP from pumpkin---Cucurmosin (Cucurmosin), and discloses its preparation method.SDS-PAGE shows that its molecular weight is 27kDa, and iso-electric point pI>9 have strongly inhibited intracellular nucleic sugar body protein synthetic activity.Cucurmosin has grown the monocrystalline that can supply X-ray diffraction to use, and crystal structure analysis is the result point out, Cucurmosin and Trichosanthin have structural homology [Chen et al.Acta Cryst.D56 2000,665-666; Shi etal:Chinese J.struct.chem.2003,22 (2), 165-168].
The present invention is based on above-mentioned prior art basis, has confirmed Cucurmosin glycosidase activity of the same RNA of having N-with Trichosanthin and anti-tumor activity, and the experiment basis of its application is provided.
Summary of the invention
The purpose of this invention is to provide the anti-tumor activity and the application thereof of Cucurmosin, realize that the technical scheme of the object of the invention is as follows:
Adopt gentle separation purification method, comprise that strong or weak positively charged ion gel media secondary ions displacement chromatographies such as salts solution extracting, the filtration of DEAE-Mierocrystalline cellulose, CM-Mierocrystalline cellulose or SP-agarose separate, can from pumpkin fruit, be separated to Cucurmosin, SDS-PAGE detection molecules amount is 27kDa, it is alpha-helix that garden two chromatograms detect its secondary structure, beta sheet, and disordered structure is respectively 30.8%, 41.7%.27.4%, similar to Trichosanthin.
Ribosome inactivating protein of the present invention can be used for the treatment of the relevant tumour of trophocyte, malignancy disease as the drug inducing labor raw material, as suede cancer etc., also can be used as the alternative medicine raw material of Trichosanthin, be used to overcome and use the immune response that produces repeatedly.
Ribosome inactivating protein of the present invention can be as antiviral, and particularly the medicine material of anti AIDS virus also can be used as the alternative medicine raw material that Trichosanthin is treated acquired immune deficiency syndrome (AIDS), is used to overcome use the immune response that produces repeatedly.
Ribosome inactivating protein of the present invention can be used as the antitumour drug raw material, also can be used as the alternative medicine raw material of Trichosanthin treatment tumour.
Ribosome inactivating protein of the present invention can be used as the N-Glycosylase and is used for molecular biology and immunology research.
Ribosome inactivating protein of the present invention can be used as the toxin material of immunotoxin or the toxin material of fusion rotein, is used for the treatment of tumour and virus disease, particularly acquired immune deficiency syndrome (AIDS).
The present invention compared with prior art has following positively effect:
(1) secondary structure of Cucurmosin and Trichosanthin are similar;
(2) Cucurmosin has RNA N-glycosidase activity;
(3) Cucurmosin has stronger cytotoxicity to human leukemia cell line K562.Half-inhibition concentration (IC
50) be 3.3 * 10
-7Mol/L.
Description of drawings
Now accompanying drawing is made drawing explanation: Fig. 1. show the Cucurmosin anti-tumor activity, 1,2 be Trichosanthin, and 3,4 is Cucurmosin, and 1,3 handle without aniline for sample, 2,4 after the aniline processing visible 450 Nucleotide feature segments; Fig. 2. show Cucurmosin circular dichroism collection of illustrative plates; Fig. 3. show the Cucurmosin anti-tumor activity; ▲ be Cucurmosin, ● be Trichosanthin.
Embodiment
Further describe the present invention below in conjunction with accompanying drawing by embodiment:
Embodiment 1. Cucurmosins of the present invention, press the method (Acta Biochimica et Biophysica Sinica 2000 of Zhang Zuchuan etc., 32 (5) 495-498) measure it to rats'liver ribosome-RNA(rRNA) N-glycosidase activity, and with Trichosanthin relatively, see Fig. 1, show the same RNA of the having N-of Cucurmosin glycosidase activity with Trichosanthin.
Embodiment 2. Cucurmosins of the present invention are measured on Japanese Jasco-810 type circular dichroism spectrometer, see Fig. 2, and the secondary structure content and the Trichosanthin that calculate it by least square fitting method are similar:
| Cucurmosin | Trichosanthin
① |
Alpha-helix | ???30.8% | ????31.9% |
Beta sheet | ???41.7% | ????30.5% |
Random coil | ???27.4% | ????37.9% |
1. see old generation sesame etc., Acta Biophysica Sinica 1989,5 (2) 188-250
Embodiment 3. Cucurmosins of the present invention, (monoclonal antibody communication 1995,11 (1): 39-42) measuring it has stronger cytotoxicity to human leukemia cell line K562, half-inhibition concentration (IC to press the method for Xie Jieming etc.
50) be 3.3 * 10
-7Mol/L sees Fig. 3.Human leukemia cell line K562 in the RPMI-1640 nutrient solution that contains 15% deactivation calf serum, 37 ℃, 5%CO
2Cultivate under the condition, cell concn is adjusted into 5 * 10 with nutrient solution
5/ ml adds the Cucurmosin and the Trichosanthin of different concns respectively, every hole 100 μ l, 3 multiple holes.Negative control hole adds physiological saline, and the positive control hole adds enchylema, and behind the cultivation 72h, every hole adds 20 μ l MTT (5mg/ml), continues to cultivate 3-4h, the centrifugal supernatant liquor that goes, and each hole A is measured with microplate reader after adding 100 μ l DMSO vibration dissolving in every hole
550Value.