Experimental Study Of ¹³¹ⅠMarked The Preparation Of New Targeted FGF8 Molecular Probe And Its Effect On Prostate Cancer Cells In Vitro

Objective: To explore the best condition of the 131 I labeled small peptides H SQAAVP, which is the targeting fibroblast growth factor 8(FGF8) by 131 I.To g et radiochemical purity higher than 95% of the131I-HSQAAVP, study the stabili ty and biological activity of that labeled product in vitro. To research it s role on the treatment of prostate cancer LNCa P cells and DU145 cells invi tro.Methods: Use 131 I labeled peptide HSQAAVP with method Chloramine-T to filtrat e the best mark condition through orthogonal experiment. Get the labeled p roduct 131I-HSQAAVP by thin layer chromatography(TLC) measuring mark rate an d radiochemical purity, and by Sephadex G25 column chromatography separatio n. The new molecular probes purified 131I- HSQAAVP(radiochemical purity > 95%) are placed respectively at room temperature water and 37 ℃ serum, to observe the stability at different times by measuring its radiochemical purity.Method CCK-8 proliferation inhibition experiment are applied to hu man prostate cancer of LNCa P cell and DU145 cells in vitro culture to c alculate respectively the inhibition rates of HSQAAVP and the 131I- HSQAAVP on LNCa P cell and DU145 cell, and to determine the 131I-HSQAAVP biological activities. To join LNCa P cell and DU145 prostate cancer cell lines in v itro, respectively, with 131I- HSQAAVP in different radioactivity, HSQAAVP i n same concentration and blank controlgroup, after 48 h intervention using o ptical microscope, laser confocal microscope and flow cytometry analysis to identify the therapeutic effect of 131I- HSQAAVP to prostate cancer LNCa P cells and the of DU145 cell lines.Results: In the best mark condition, to join PBS buffer solution of the rea ction system of 50 mu L 0. 5 mol/L p H 7. 4 in HSQAAVP 50 μg and 131 I 74 Mbq(2m Ci), at room temperature(25 ℃) in 5min reaction, the mark rate can re ach more than 70%. After Sephadex G25 column chromatography separation a nd purification, the radiochemical puritycan reach more than 95%. The exper imental results of stability show that,after 24 h, both in vitro and in ser um,the radiochemical purity of 131I- HSQAAVP > 90%.Neither 131I- HSQAAVP nor HSQAAVP has statistical significance on proliferation inhibition rate of prostate cancer LNCa P cell and the DU145(P > 0.05), which illustrates that the biological activities of 131 I labeled HSQAAVP have not been changed. G reen fluorescein FITC combining with prostate cancer through small molecula r peteide HSQAAVP by its connecting specificity,is absorbed by cells. Und er laser scanning confocal microscope, FITC-HSQAAVP with prostate cancer LN Ca P cells and DU145 cells in 37 ℃ after 24 h, appear strong green fluoresc ence colour under the green fluorescence channel. The ability of cells to a bsorb green fluorescent reflects the combining ability of small molecular p etides HSQAAVP, both are positively correlated. Which illustrates that Andr ogen hormone has strong ability of combining with HSQAAVP by depending on either sensitive LNCa P cellsor insensitive DU145 cells.Conclusion: The 131 I babeled peptides HSQAAVP by method chloramines-T simple and efficient, and the biological activity of new molecular probes 131I-HSQA AVP remains unchanged, which has not obvious damage. 131I-HSQAAVP plays a significant role in therapy for prostate cancer LNCa P cells and DU145 cell, and new molecular probes provides theoretical basis and foreshadowing for 131I-HSQAAVP using in animal experiment and clinical application.