异黄酮对前列腺癌细胞及PTEN基因的影响

Study of isoflavones on inhibition of prostate cancer cells and effects on PTEN gene

目的 通过大豆异黄酮抑制前列腺癌PC 3和LNCaP细胞生长和相关基因表达的影响 ,探讨大豆异黄酮类抑制前列腺癌的机制。方法 对染料木黄酮和大豆甙元作用后的雄激素非依赖型前列腺癌 (PC 3 )、雄激素依赖型前列腺癌LNCaP细胞的存活率、细胞毒作用、细胞周期和PTEN基因的mRNA表达等进行了研究。结果 染料木黄酮和大豆甙元对PC 3、LNCaP细胞抑制效应具有时间和剂量依赖性 ,具有诱导凋亡和引起坏死效应 ;染料木黄酮能诱导PC 3和LNCaP细胞的 (PTEN)表达 ,而大豆甙元只能诱导LNCaP细胞PTEN表达。结论 PTEN基因表达的变化可能在染料木黄酮和大豆甙元抑制PC 3和LNCaP细胞中具有重要的意义。染料木黄酮和大豆甙元抑制PC 3和LNCaP细胞可能存在多种作用途径。

Objective To explore the possible mechanisms in terms of the viability of prostate cancer cells and the changes of PTEN gene expression after incubation with genistein and daidzein.Methods In the present study,LNCaP cells and PC-3 cells were exposed to varying doses of genistein and daidzein to evaluate viability and cytotoxicity by use of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) and lactate dehydrogenase (LDH).Flow cytometry (FCM) were used to assess the cycle in LNCaP and PC-3 cells by treatments with genistein and daidzein.Reverse transcription-polymerase chain reaction(RT-PCR) was conducted to examine the level of mRNA of the tumor suppressor gene (PTEN).Results The results showed:genistein and daidzein exerted a time and dose-dependent inhibitory effects on both prostate cancer cell lines;Genistein and daidzein manifested dual cell death pathways,apoptosis and necrosis,depending on doseage.Genistein induceed expression of PTEN in PC-3 and LNCaP,and daidzein induceed expression of PTEN in LNCaP but not in PC-3. Conclusion It is indicated that the expression of PTEN may play a critical role and there maybe several pathways in the process of growth inhibition caused by genistein and daidzein.