多西紫杉醇治疗前列腺癌的分子机制研究

  目的  探讨多西紫杉醇治疗男性雄激素抵抗前列腺癌(castration-resistant prostate cancer, CRPC)的分子机制。  方法  前列腺癌细胞株LNCaP、PC-3和CW22-rv1体外培养后, 通过蛋白质印迹、细胞转染、荧光素酶分析、细胞存活率分析等试验分析多西紫杉醇(Docetaxel, Doc)处理后细胞株的存活、AR及p-c-jun的表达情况及其与细胞生存的关系, 同时实时定量PCR检测相应mRNA的表达情况。  结果  多西紫杉醇对不同前列腺癌细胞株的敏感性不同, 其中PC-3细胞最敏感, CW22-rv1和LNCaP细胞中度敏感, 其敏感性与p-c-jun表达呈负相关。转染c-jun基因可降低细胞对多烯紫杉醇的敏感性, 而PC-3细胞转染c-jun和AR基因后则可以使细胞恢复到中等程度敏感性, 细胞存活率为30%。长期暴露于Bicalutmide(比卡鲁胺)后的LNCaP细胞经Doc处理后PSA蛋白表达增加, AR蛋白表达水平降低, AR的mRNA却增加。  结论  p-c-jun降低前列腺癌细胞株对多西紫杉醇的敏感性, 而AR可以增加前列腺癌细胞株对多西紫杉醇的反应, AR的上调降低c-jun/p-c-jun的转录活性, 从而增加前列腺癌细胞株对Doc的反应, 可能是Doc治疗前列腺癌的机制之一。 

Molecular mechanism of docetaxel response in prostate cancer cells

  Objective  The present study investigated the biochemical mechanism of docetaxel(Doc) for the treatment of castration-resistant prostate cancer(CRPC).  Methods  The prostate cancer cell lines PC-3, LNCaP, and CW22-rv1 were grown in vitro.The expression of c-Jun and the androgen receptor(AR), the relationship between their expression levels, and the viability of LNCaP, PC-3, and CW22-rv1 cells after exposure to Doc were studied in vitro by immunoblot, luciferase, and viability assays.Furthermore, the expression of AR mRNA was analyzed by quantitative real-time polymerase chain reaction(RT-PCR).  Results  Doc therapy elicited different responses in the different cell lines.PC-3 cells were the most sensitive to treatment, whereas a moderate response was observed in CW22-rv1 and LNCaP cells.The sensitivity and response to Doc was negatively correlated with the level of phosphorylated c-Jun(p-c-Jun) expression.Transfection of the c-jun gene into cell lines decreased their response to Doc treatment, whereas cotransfection of the c-jun and AR genes restored the sensitivity of PC-3 to a moderate degree, with 30% viability was 30%.After long-term exposure to bicalutamide(cas), the Doc-treated LNCaP cells demonstrated increased levels of the prostate specific antigen(PSA).Likewise the AR protein levels decreased with increasing AR mRNA expression.  Conclusion  This study demonstrated that the level of p-c-Jun decreased the response of PC cells to Doc treatment, but the level of AR increases PC cells response to Doc treatment.The increased AR level inhibits c-Jun/p-c-Jun transcriptional, which decreases the protective effects of Doc in PC cells.