CN104447955B - A kind of polypeptide combined with PSMA film outskirt targetings and its application - Google Patents

Abstract

The invention belongs to medical domain, discloses a kind of polypeptide combined with PSMA film outskirt targetings and its application.The amino acid sequence of the polypeptide such as SEQ ID No:Shown in 1, which mediates radionuclide to be marked by coupling agent, available for the target medicine for preparing treatment or diagnosis of prostate cancer.

Description

A kind of polypeptide combined with PSMA film outskirt targetings and its application

Technical field

The invention belongs to medical domain, is related to a kind of polypeptide combined with PSMA film outskirt targetings and its application.

Background technology

Prostate cancer (PCa) has become the major malignant tumor of the global men's health of harm at present, and early stage is mainly by outer Section performs the operation and radiotherapy, but early detection is difficult, and DISTANT METASTASES IN has occurred for majority when medical.The PCa cells of untreated are more For androgen-dependent, i.e., by blocking androgen to promote ndrogen-dependent cancer Apoptosis, but androgen-dependent PCa is passed through It is most of to switch to non-hormone dependence prostate cancer (androgen after a while after (the average 14-30 months) endocrine therapy Independent prostate cancer, AIPC), it is eventually converted into hormone-refractory prostate cancer (Hormone Refractory prostate cancer, HRPC), effective treatment method is there is no for HRPC and its transfer stove at present, is faced Bed is referred to as refractory prostate cancer, be cause PCa poor prognosis, the main reason for death rate is high.

¹²⁵I、¹⁰³Pd particles plesioradiotherapy and outer radiotherapy are the treatment means of HRPC, but are limited primarily to local disease Stove.Receive much concern in recent years for radiation treatment in the targeting of multiple lesion,¹⁷⁷Lu is preferable targeting internal radiotherapy core Element, is usually used in the mark of antibody, polypeptide and the like etc., and¹⁷⁷Lu is produced by pileradiation, is had inexpensive and easy Property is obtained, there is suitable physical half time (6.7d), the beta particle linear energy transfer and biological effect of transmitting are higher than¹²⁵I, group Mean range is knitted less than 200 μm, is adapted to kill cancer cell, the gamma-rays of transmitting can be used for SPECT imagings, to monitor and guidance is controlled How treatment process, therefore, increase desired therapeutic nucleic¹⁷⁷Lu assembles in the targeting of HRPC and transfer stove and delay is to improve It is particularly important that its prognosis problem urgently to be resolved hurrily, the wherein selection of acceptor and ligand.

Prostate-specific membrane antigen (prostate specific membrane antigen, PSMA) is a kind of II types Transmembrane glycoprotein, its size are about 100-120kD.It is made of 3 parts：Short intracellular section (amino acid/11-18), cross-film section (ammonia Base acid 19-43) and longer extracellular fragment (amino acid 44-750), in the swollen of high malignancy primary PCa, HRPC and its transfer stove Oncocyte surface is expressed in high abundance, and is raised with PCa malignant progressions, and normal in prostate, kidney, lungs, liver etc. Tissue, inflammatory hyperplasia tissue and other benign lesion cell surface expressions are extremely low, do not express even, become HRPC and its The major target proteins of transfer stove targeted therapy.

As ligand, polypeptide is small compared with antibody molecule amount, and stability is good, no immunogenicity, not by the non-spy of reticuloendothelial system Opposite sex intake, can connect the conjugates such as NOTA, CB-TE2A, PCTA, DOTA by chemical modification, carry out radioisotope labeling, External class synthesis (such as solid phase method) process is simple, economical, provides the foundation for extensive clinical practice.Importantly, polypeptide is made For radionuclide carrier, by structure optimization can obtain internal pharmacokinetics well as serum except it is fast, targeting specific is good, With reference to stable polypeptide.

Also it can then be easier to modification with reference to effect with preferable in addition, if polypeptide fragments are shorter and synthesize in vitro, more Beneficial to quantization and industrialization production.Can be with PSMA extracellular regions specific binding characteristics and with targeting work(if one kind can be developed The shorter polypeptide being readily synthesized of segment of energy, diagnose and treat and industrialization for PCa have preferable application prospect.

The content of the invention

The purpose of the present invention is provide a kind of polypeptide combined with PSMA film outskirt targetings for above-mentioned technical problem.

It is a further object to provide the radioisotope labeling polypeptide prepared by aforementioned polypeptides.

It is a still further object of the present invention to provide in the target medicine that aforementioned polypeptides prepare treatment or diagnosis of prostate cancer Application.

The purpose of the present invention is what is realized by following technical proposal：

A kind of polypeptide combined with PSMA film outskirt targetings, the amino acid sequence such as SEQ ID No of the polypeptide:Shown in 1.

A kind of radioisotope labeling polypeptide, the radioisotope labeling polypeptide are that aforementioned polypeptides are mediated by coupling agent Radionuclide is marked.

The radioisotope labeling polypeptide, wherein coupling agent are DOTA, NOTA, CB-TE2A or Hynic.

The polypeptide that the radioisotope labeling polypeptide, wherein the PSMA film outskirts targeting combine passes through with coupling agent Polyethylene glycol (PEG_n, n=1,2,3) connection.

The radioisotope labeling polypeptide, wherein radionuclide are resulting visualization radionuclide or therapeutic radiation Property nucleic.Resulting visualization radionuclide is such as⁶⁴Cu、⁶⁸Ga、¹¹¹In、^99mTc, Therapeutic radionuclides are such as⁹⁰Y、¹⁷⁷Lu、⁸⁹Sr。

Described is preparing the targeting medicine for the treatment of or diagnosis of prostate cancer with the polypeptide that PSMA film outskirt targetings are combined Application in thing.

Application of the radioisotope labeling polypeptide in the target medicine for the treatment of or diagnosis of prostate cancer is prepared.

The small molecule straight line polypeptide that the external Solid phase synthesis PSMA films outskirt targeting of this seminar first passage combines, its Structure is that polypeptide sequence is Ser-His-Phe-Ser-Val-Gly-Ser (SEQ ID No:1), i.e. serine-histidine-phenylpropyl alcohol Propylhomoserin-Serine-Valine-glycine-serine (hereinafter referred to as PTP), can be with PSMA extracellular fragments (amino acid 44-750) target Pass through polyethylene glycol (PEG to combination, and with coupling agent (such as DOTA, NOTA, CB-TE2A, Hynic)_n, n=1,2,3) even Connect, the radionuclide of coupling agent direct polypeptide is (such as⁶⁸Ga、⁶⁴Cu、¹¹¹In、¹⁷⁷Lu and^99mTc mark).Experiment in vitro is examined or check Its vitro stability, experiment in vivo investigate its internal pharmacokinetics and biodistribution, and by MicroPET/CT (or MicroSPECT/CT) Imaging Evaluation its prostate cancer position radioactive uptake.

Beneficial effects of the present invention：

Micromolecule polypeptide PTP prepared by the present invention, can be combined with PSMA film outskirt targetings, be put using prepared by the polypeptide Penetrating property isotope labeling polypeptide, can have preferable effect as the target medicine for diagnosing or treating prostate cancer.

Synantibody is different, and the polypeptide is without immunogenicity, and molecular weight is small, and blood removes fast, the richness reticuloendothelial system such as liver and spleen Intake is less and removing is fast, and distribution is few in the tissue such as prostate, and dense poly- more in prostate cancer (and its transfer) lesions position, and Holdup time is grown, can be effectively as the carrier of diagnose and treat radionuclide.

The outer head of district of PSMA films, the screening and acquisition for the polypeptide sequence that high specific combines are difficult, this micromolecule polypeptide nucleosides Acid sequence is obtained (display technique of bacteriophage is known technology, and screening process repeats no more) by display technique of bacteriophage, this is more Peptide is shorter, it is easier to which modification and external synthesis, can be prepared by external solid-phase synthesis, beneficial to quantization and industrialization production.

Brief description of the drawings

Fig. 1 is the HPLC inspection figures of DOTA-PTP.

Fig. 2 is DOTA-PTP mass spectrograms.

Fig. 3 is⁶⁸The radioactivity peak of the HPLC analyses of Ga-DOTA-PTP.

Fig. 4 is⁶⁸The ultraviolet peak of the HPLC analyses of Ga-DOTA-PTP.

Fig. 5 is prostate cancer (LNCAP) lotus knurl tail vein injection⁶⁸Row microPET/CT after Ga-DOTA-PTP 60min (upper row is Coronal, and lower row is cross-section position, and left, center, right are respectively CT, SPECT and SPECT-CT blending image, thin arrow for imaging Head show subcutaneous tumor shadow, and block arrow is kidney and bladder shadow).

Fig. 6 is mice with tumor (prostate cancer LNCAP and cancer of pancreas PC-3) tail vein injection¹⁷⁷It is different before and after Lu-DOTA-PTP The tumor volume change of time compares.

Fig. 7 is prostate cancer (LNCAP) lotus knurl tail vein injection¹⁷⁷3d after Lu-DOTA-PTP, 5d, 15d tumor tissues (HE is dyed pathological examination results：×10).

Embodiment

The invention will be further elaborated by the following examples.

Embodiment 1

First, the synthesis and its Quality Control of polypeptide DOTA-PTP

1st, the synthesis of solid phase method straight line polypeptide PTP and with Cyclen -1,4,7,10- tetraacethyls (DOTA) coupling

1. polypeptide from C-terminal to N-terminal direction composition, first amino acid is first hung on resin, weighs 2.0g resins in cleaning In dry reaction tube, appropriate dimethylformamide (DMF), activation 30min or so are added, then weighs first amino acid Fmoc-Ser (But)-OH 0.5mmol, 4-dimethylaminopyridine (DMAP) 75mg, N, N'- diisopropylcarbodiimide (DIC) 1ml is added in reaction tube, and DMF is solvent reaction 3h.Reaction is finished is washed 4~6 times with DMF, adds appropriate pyridine and methanol, body Product is than being 1:1, react 30min.Reaction is finished is washed 4~6 times with DMF.Then the Fmoc of amino acid is taken off with piperidine solution, takes off two Secondary common 15min, 10min+5min.To be washed 4 times with DMF again, methanol is washed 2 times, takes out a small amount of resin ninhydrin detection reagent detection, It is detected as blueness, you can carry out next step reaction；

2. second amino acid Fmoc-Gly-OH 1.5mmol is weighed, benzotriazole-N, N, N', N'- tetramethylurea six Fluorophosphoric acid ester (HBTU) 1.5mmol adds DIEA 0.5ml in reaction tube, reacts 40min, is washed 4~6 times with DMF, takes a small amount of Resin is detected with ninhydrin detection reagent, shows colourless, is then added piperidine solution and is taken off Fmoc, 10min+5min, is then washed with DMF 4 times, methanol is washed twice, is taken out a small amount of resin ninhydrin detection reagent detection, is detected as blueness, you can carries out anti-in next step Should；

3. following amino acid reaction method is the same as 2.；Amino acid classes press SEQ ID No:Reversely it is stepped up shown in 1, finally Obtain SEQ ID No:Polypeptide shown in 1, i.e. Ser-His-Phe-Ser-Val-Gly-Ser.

4. weighing 0.75mmol DOTA, HBTU 1.5mmol add n,N-diisopropylethylamine (DIEA) in reaction tube 0.25ml, by being detected with ninhydrin detection reagent, is detected as colourless；

5. finally filtered with trifluoroacetic acid cutting liquid cutting 2h, reaction solution, obtained the trifluoroacetic acid solution of polypeptide, sunk with ether Form sediment, centrifugation, is then washed 3~5 times with ether, obtain white solid, purified through HPLC again, is freezed, and takes a small amount of progress quality analysis.

2nd, quality analysis：

Peptide sequence, molecular weight and chemistry are carried out to target compound using high performance liquid chromatograph (HPLC) and mass spectrograph (MS) Purity carries out quality analysis

HPLC is analyzed：Parameter：C18 columns, (4.6 × 250mm), mobile phase：Solvent orange 2 A is containing 0.1% trifluoroacetic acetonitrile (Acetonitrile), solvent B is as follows containing 0.1% trifluoroacetic ultra-pure water, eluent gradient：

Flow velocity：1.0ml/min, ultraviolet wavelength：220nm, injection volume are 10 μ l.

Mass spectral analysis condition：

Flow rate:0.2ml/min Run Time:1min

Buffer A:0.1%HCOOH in water Buffer B:0.1%HCOOH in Acetonitrile

Two, results

1.DOTA-PTP peptide molecule structural formulas are shown in formula 1.

2. Quality Control image

(1) the HPLC inspection results of DOTA-PTP are shown in Fig. 1.

DOTA-PTP chemical purities：95.35%, storage：- 4 DEG C or -20 DEG C are relatively stablized.

HPLC images are as follows：The appearance time of DOTA-PTP is 9.446min.

(2) the result is shown in Fig. 2 for the mass spectrogram of DOTA-PTP.

Molecular weight:1106.18 good water solubility.

Embodiment 2：⁶⁸The preparation of Ga-DOTA-PTP and inside and outside experimental study

First,⁶⁸The preparation of Ga-DOTA-PTP

It is 2mg/ml to configure DOTA-PTP polypeptide solutions, and HEPES is 1M (pH：7),⁶⁸GaCl₃For 1-10mCi/ml.

Taking the HEPES liquid of 25 μ l, (a kind of nonionic both sexes buffer solution, component are 4- hydroxyethyl piperazineethanesulfonic acids, distilled water And sodium hydroxide) (concentration 1M), distribution sequentially adds 0.7-5 μ l DOTA-PTP polypeptide solutions (2mg/ml) and 100 μ l⁶⁸Ga Cl₃(radioactive concentration 1-10mCi/ml), is placed in 95 DEG C of water-bath and heats, and reaction 15-20min is obtained⁶⁸Ga-DOTA- PTP。

2nd,⁶⁸Ga-DOTA-PTP experiment in vitro

⁶⁸After Ga-DOTA-PTP synthesis, it is detected by radioactivity-HPLC, method and parameter are the same, as a result show Show⁶⁸The ultraviolet peaks of HPLC and radioactivity peak of Ga-DOTA-PTP occurs in same time, sees Fig. 3 and 4, top coal drawing (98.4 ± 0.35%) 37 DEG C of incubations, and in hyclone, take 20ul to carry out HPLC inspections, as a result have no respectively after placing 2h, 4h, 6h⁶⁸Ga Free peak, shows that its vitro stability is good, and top coal drawing is (96.3 ± 0.28%) during 6h.

3rd,⁶⁸Ga-DOTA-PTP mice with tumor vivo biodistribution credit cloth

(1) sampling randomly selects lotus prostate cancer (LNCap, PSMA are positive) nude mice 30 (male, 18 ± 2g of weight), It is divided into 6 groups (1-5 groups are experimental group, and the 6th group is receptor blocking closed group), every group 5, respectively in tail vein injection radioactive nucleus Element mark PSMA target polypeptides are (such as⁶⁸Ga-DOTA-PTP) (74kBq/0.1mL i.e. 2.0 μ Ci/0.1mL) afterwards 5,15,30,60, 120min, excessive (200mg/Kg weight) benzobamylum sodium intraperitoneal injection euthanasia, heart puncturing extracting blood 1.0ml, and solve Subdivision blots surface from the internal organs such as tumour, the heart, liver, spleen, lung, kidney, stomach, intestines, brain, muscle, bone, physiological saline cleaning, filter paper Moisture, claims weight in wet base, and γ calculating instruments (Perkin Elmer Wizard-1480, Shelton, CT) measure radiocounting simultaneously records Time, and the net radioactive activity of injection is calculated, the radioactivity that each time point main organs are calculated after radiation decay correction down accounts for It is every that the radioactivity of the percentage (ID%) and/or unit mass internal organs that inject gross activity count per minute accounts for injection gross activity The percentage (%ID/g) of minute flicker number.Stool and urine investigation radioactivity excretion is collected respectively and HPLC investigates it and stablizes in vivo Property.Wherein, receptor blocking closed group：Every mouse is through vein preform injection PTP (10mg/Kg weight), then tail vein injection⁶⁸Ga- 60min is put to death after DOTA-PTP, and binding specificity is investigated in the experiment of row biodistribution (experimentation is the same).

As a result：⁶⁸For Ga-DOTA-PTP after prostate cancer lotus knurl tail vein injection, blood background activity removes fast, medicine Mainly it may occur in which that liver kidney position radioactivity substantially lowers through liver and kidney excretion, 60min, the increase of enteron aisle radioactive uptake, Considering may be with⁶⁸Ga-DOTA-PTP is drained through enteron aisle and part, the normal structure such as brain, lung, prostate related through enteron aisle reabsorption Absorb it is low, after medicine tail vein injection during 60min prostate cancer/prostata tissue radioactive uptake ratio be 4.85 ± 0.47. After PSMA receptor blockings, prostate cancer subcutaneous transplantation knurl radioactive uptake is substantially blocked during 60min, radioactive uptake (%ID/ G) it is (1.36 ± 0.69), does not block group (6.03 ± 0.47) substantially less than.

Table 1：Prostate cancer mice with tumor is injected⁶⁸Each internal organs radioactive uptake (%ID/ of different time points after Ga-DOTA-PTP G, n=5)

Note：Every group of mouse number is 5, and 60minB is receptor blocking closed group data.Data withRepresent.

4th,⁶⁸Ga-DOTA-PTP prostate cancers (LNCAP) mice with tumor microPET/CT is imaged

Prostate cancer (LNCAP) lotus knurl tail vein injection 0.1mL (3.7MBq)⁶⁸50min after Ga-DOTA-PTP, is placed in Anaesthetize in box, anaesthetized in advance using 3% isoflurane (Isoflurane) under the oxygen gas flow rate of 3L/min.Put after pre- anesthesia Enter MicroPET/CT device scan beds and be scanned imaging (continuous narcosis of the 1.5% different fluorine of 2L/min).Micro PET/ CT equipment acquisition workstation is Inveon Acquisition Workplace (IAW) 1.5.0.28, static scanning data acquisition Order is in 80kV voltages, 500 μ A electric currents and scanning computed tomography data 10min under the 1100ms time for exposure, then surveys dynamic acquisition PET Data 60min.The data result of collection is dispersed through using IAW softwares, random counter, coincidence correction, pass through filtered back projection Method (Filtered Back projection) reconstruction coronal-plane, cross section, sagittal plane faultage image are analyzed.Using Inveon ResearchWorkplace softwares, based on PET/CT blending images, delineate tumour region of interest (Regions of Interest, ROI), calculate tumour radiotherapy intake and tumour/muscle (T/M) radioactive uptake ratio.

As a result：See Fig. 5, the visible obvious radioactive uptake of tumor locus, tumour/muscle ratio is 9.7 ± 3.1, tumour portion Position SUV is 6.8 ± 2.5, and the important organ such as liver, spleen, lung is showed no obvious radioactive uptake, and enteron aisle and bladder are visible obvious Increased radioactivity, prompts polypeptide mainly to be drained by liver and gall and urinary system, and drains very fast.

Embodiment 3：⁶⁴The preparation of Cu-DOTA-PTP and inside and outside experimental study

Except radionuclide is⁶⁴CuCl₂Outside, remaining is the same as embodiment 2.

As a result 1：⁶⁴Cu-DOTA-PTP radio-chemical purities are (98.3 ± 1.31%), and 37 DEG C of temperature in physiological saline Educate, take 20ul to carry out HPLC inspections respectively after placing 2h, 4h, 6h, as a result have no⁶⁴Cu dissociates peak, shows that its vitro stability is good, Top coal drawing is (96.5 ± 0.76%) during 6h.

As a result 2：Prostate cancer mice with tumor⁶⁴After Cu-DOTA-PTP tail vein injections, vivo biodistribution credit cloth with⁶⁸Ga- DOTA-PTP is similar, considers that main cause depends primarily upon DOTA-PTP for its vivo biodistribution characteristic distributions, shows as main Through liver and kidney excretion, remove soon, 60min may occur in which that liver kidney position radioactive uptake substantially lowers, enteron aisle radioactive uptake Increase, brain position radioactive uptake continue relatively low, and prostate normal structure radioactive uptake is significantly lower than tumour, and when 60min swells Knurl/prostata tissue radioactive uptake ratio is (4.86 ± 0.46).After PSMA receptor blockings, prostate cancer is subcutaneous during 60min Transplantable tumor radioactive uptake is substantially blocked, and radioactive uptake (%ID/g) is (1.47 ± 0.5), does not block group substantially less than (5.07±0.75)。

2 prostate cancer mice with tumor of table is injected⁶⁴Each internal organs radioactive uptake (%ID/g) of different time points after Cu-DOTA-PTP

Note：Every group of mouse number is 5, and 60minB is receptor blocking closed group data.Data withRepresent.

Embodiment 4：¹¹¹The preparation of In-DOTA-PTP and inside and outside experimental study

Except radionuclide is¹¹¹Outside In, remaining is the same as embodiment 2.

As a result 1：¹¹¹In-DOTA-PTP top coal drawings (97.5 ± 1.65%), and 37 DEG C of incubations in physiological saline, placement 2h, Take 20ul to carry out HPLC inspections after 4h, 6h respectively, as a result have no⁶⁴Cu dissociates peak, shows that its vitro stability is good,

Top coal drawing is (96.4 ± 0.77%) during 6h.

As a result 2：Prostate cancer lotus knurl tail vein injection¹¹¹After In-DOTA-PTP, vivo biodistribution credit cloth with⁶⁸Ga- DOTA-PTP is similar, its blood background activity is removed fast, and mainly through liver and kidney excretion, when 60min shows as liver kidney portion Position radioactive uptake substantially lowers, and enteron aisle and the internal organs radioactive uptake such as bladder radiation intake increase, brain, lung are lasting relatively low, Prostate normal structure radioactive uptake is significantly lower than tumour, and tumour/prostata tissue radioactive uptake ratio is during 60min (5.26±0.56).After PSMA receptor blockings, prostate cancer subcutaneous transplantation knurl radioactive uptake is substantially blocked during 60min, is put Penetrating property intake (%ID/g) is (1.63 ± 0.6), does not block group (5.12 ± 1.57) substantially less than.

3 prostate cancer mice with tumor of table is injected¹¹¹Each internal organs radioactive uptake (%ID/ of different time points after In-DOTA-PTP g)

Note：Every group of mouse number is 5, and 60minB is receptor blocking closed group data.Data withRepresent.

Embodiment 5：¹⁷⁷The preparation of Lu-DOTA-PTP and inside and outside experimental study

Except radionuclide is¹⁷⁷Remaining is the same as embodiment 2 outside Lu.

As a result 1：¹⁷⁷Lu-DOTA-PTP top coal drawings (98.3 ± 1.1%), and 37 DEG C of incubations in physiological saline, placement 2h, Take 20ul to carry out HPLC inspections after 4h, 6h respectively, as a result have no¹⁷⁷Lu dissociates peak, shows that its vitro stability is good, putting during 6h Pure is (97.6 ± 1.09%).

As a result 2：Prostate cancer lotus knurl tail vein injection¹⁷⁷After Lu-DOTA-PTP, vivo biodistribution credit cloth with⁶⁸Ga- DOTA-PTP is similar,¹⁷⁷Lu-DOTA-PTP blood background activity remove it is fast, and mainly through liver and kidney excretion, table during 60min Now substantially lower for liver kidney position radioactive uptake, enteron aisle and the internal organs radioactive uptake such as bladder radiation intake increase, brain, lung Continue relatively low, prostate normal structure radioactive uptake is significantly lower than tumour, and tumour/prostata tissue radioactivity is taken the photograph during 60min It is (4.58 ± 0.47) to take ratio.After PSMA receptor blockings, prostate cancer subcutaneous transplantation knurl radioactive uptake obvious quilt during 60min Block, radioactive uptake (%ID/g) is (1.44 ± 0.82), does not block group (5.13 ± 0.8) substantially less than.

Table 4：Prostate cancer mice with tumor is injected¹⁷⁷Each internal organs radioactive uptake (%ID/ of different time points after Lu-DOTA-PTP g)

Note：Every group of mouse number is 5, and 60minB is receptor blocking closed group data.Data withRepresent.

Embodiment 6：¹⁷⁷The mice with tumor pharmacodynamics test of Lu-DOTA-PTP

Prostate cancer (LNCAP：PSMA high is expressed) subcutaneous transplantation knurl animal model point 6 groups (every group 4), pancreatic tumor borne The animal model of PC-3 (PSMA low expressions) is control group.Tail vein injection 0.1ml¹⁷⁷Lu-DOTA-PTP (17.5MBq), is controlled Mouse weight is every other day measured during treatment and measures tumour maximum major diameter and vertical minor axis with vernier caliper, passes through formula meter Calculate gross tumor volume V, calculation formula V=ab²/ 2 (a is maximum major diameter, and b is vertical minor axis), while pay close attention to mice with tumor one As situation such as diet, skin colour, the state of mind, active situation etc., dynamic monitoring medicine toxic side effect.In drug therapy The previous day (i.e. -1d), treatment 1d, 3d, 5d, 10d, 15d, every group randomly chooses 3 execution respectively, takes tumour and important organ Carry out pathological examination.

As a result：¹⁷⁷Lu-DOTA-PTP securities are good, and (17.5MBq) mice with tumor weight has no significant change after intravenous injection, PSMA high expresses LNCAP groups and reaches PC-3 group no significant differences, mice with tumor diet, skin colour, work with PSMA radiolucent tables Emotionally condition is shown no obvious abnormalities.¹⁷⁷Different time before and after Lu-DOTA-PTP lotus knurl tail vein injections, mice with tumor subcutaneous transplantation knurl Size variation is shown in Fig. 6,¹⁷⁷After Lu-DOTA-PTP intravenous injections, LNCAP prostate cancer volumes have no significant change, during 7d Gross tumor volume is slightly before treatment, but no significant difference, and the cancer of pancreas PC-3 groups that PSMA expression is negative, gross tumor volume by It is cumulative to add,¹⁷⁷The 9th day after Lu-DOTA-PTP intravenous injections, gross tumor volume (190.25 ± 71.15mm³) apparently higher than treatment Before (53.31 ± 15.86mm³) and with time LNCap group (77.11 ± 8.42mm³).Pathological examination results are shown in Fig. 7, prostate cancer It is organized in¹⁷⁷The visible stove shape necrosis of 5d after Lu-DOTA-PTP intravenous injections, visible necrotic lesion increase in 10 days, area expand Greatly, 15 days when gross tumor volume have no and be obviously reduced that but internal tumours cell is largely downright bad, no obvious tumour cell exists, liver kidney Shown no obvious abnormalities etc. main organs.

Claims (8)

1. A kind of 1. polypeptide combined with PSMA film outskirt targetings, it is characterised in that the amino acid sequence of the polypeptide such as SEQ ID No:Shown in 1.
2. 2. a kind of radioisotope labeling polypeptide, it is characterised in that the radioisotope labeling polypeptide is more described in claim 1 Peptide mediates radionuclide to be marked by coupling agent.
3. 3. radioisotope labeling polypeptide according to claim 2, it is characterised in that coupling agent DOTA, NOTA, CB- TE2A or Hynic.
4. 4. radioisotope labeling polypeptide according to claim 2, it is characterised in that polypeptide described in claim 1 and coupling Agent is connected by polyethylene glycol, and the polyethylene glycol is PEG_n, n=1,2,3.
5. 5. radioisotope labeling polypeptide according to claim 2, it is characterised in that radionuclide is resulting visualization radiation Property nucleic or Therapeutic radionuclides.
6. 6. radioisotope labeling polypeptide according to claim 5, it is characterised in that resulting visualization radionuclide is selected from⁶⁴Cu、⁶⁸Ga、¹¹¹In、^99mTc, Therapeutic radionuclides are selected from⁹⁰Y、¹⁷⁷Lu、⁸⁹Sr。
7. 7. application of the polypeptide in the target medicine for the treatment of or diagnosis of prostate cancer is prepared described in claim 1.
8. 8. application of the polypeptide in the target medicine for the treatment of or diagnosis of prostate cancer is prepared described in claim 2.