雄激素依赖性和雄激素非依赖性前列腺癌差异膜抗原的筛选

目的:探讨雄激素依赖性和非依赖性前列腺癌细胞差异表达膜蛋白的筛选方法。方法:提取雄激素依赖性前列腺癌(androgen dependent prostate cancer, ADPC) 细胞株LNCaP 和雄激素非依赖性前列腺癌(androgen independentprostate cancer, AIPC) 细胞株PC-3 膜蛋白作为抗原,采用免疫共沉淀方法,与ADPC 和AIPC 患者的血清各3 例交叉孵育,行Western 印迹检测,比较、识别杂交后差异表达蛋白条带,串联质谱分析鉴定,细胞免疫荧光和组织免疫组织化学方法验证。结果:共获得11 个差异表达的膜蛋白(Neural-Cadherin precursor,ER60 precursor, Claudin-4 等);细胞免疫荧光结果显示Claudin-4 在LNCaP 和PC-3 细胞存在明显差异,在ADPC 组织中阳性表达率(34.3%) 低于AIPC 组织中阳性表达率(72.4%, P<0.05)。结论:本研究所采用的方法筛选前列腺癌差异表达膜蛋白具有可行性;Claudin-4 可能在雄激素非依赖性前列腺癌的发生和发展中发挥重要的作用。

Screening of membrane antigen differentially expressed in androgen-dependent prostate cancer and androgenindependent prostate cancer

Objective: To determine the screening of the expression of membrane proteins in androgendependent prostate cancer (ADPC) and androgen-independent prostate cancer (AIPC) and to explore the mechanism of membrane proteins in these two cancers. Methods: Serum samples were collected from 3 patients with ADPC and another 3 patients with AIPC. The serum was incubated with ADPC cell line LNCaP and/or AIPC cell line PC-3 and detected by immunoprecipitation and Western blot. Differentially expressed proteins between ADPC and AIPC identified by mass spectrometry were compared and their expression level and location were analyzed by immunofluorescence. Results: Altogether 11 membrane proteins were identifited, such as the Neural-Cadherin precursor, ER60 precursor, Claudin-4, and so on. Immunofluorescence revealed that the expression level of Claudin-4 in PC-3 cells was higher than in LNCaP cells. Conclusion: We can use the screening method to study membrane proteins in prostate cancer. Claudin-4 may play an important role in the pathogenesis and the development of AIPC.