Department of Urology, Huashan Hospital, Fudan University, Shanghai, China.
Panminerva Med. 2012 Sep;54(3):219-23.
Cyclin D1 is an important cell cycle regulatory proteins, which is a functional target of Slug in the regulation of cell growth of prostate cancer cells. But the pathway of these two factors interacting with each other is unclear.
The infectde PCa Cells were treated with proteasome inhibitor MG-132. Expression level of Slug, HA-cyclin D1 and other protein was examined by Western blot.
Increasing doses of adenovirus expressing human Slug were added to DU-145 cells separately, but there were no significantly difference on expressions of Slug and cyclin D1. We found that the protein expressions of HA-Cyclin D1 (wide-type) were all reduced through high expression of Slug, which is dose-dependent. However, there is no change for HA-Cyclin D1 (mutant) expression in PC-3 with pMIGW-Cyclin D1-HA T286A. The protein expression of HA-Cyclin D1 were all reduced three days after infection by adding adenovirus expressing human Slug to PC-3 carrying pMIGW-Cyclin D1-HA vector compared to negative control, which is dose-dependent. However, there is no change for HA-Cyclin D1 expression in PC-3 with pMIGW-Cyclin D1-HA treated by MG-132.
We found that forced expression of Slug inhibited proliferation of prostate cancer cells through downregulation of cyclin D1 expression. And Slug regulates cyclin D1 expression by ubiquitin-proteasome pathway in PCa cells.
细胞周期蛋白 D1 是一种重要的细胞周期调控蛋白，它是 Slug 在调节前列腺癌细胞生长中的功能靶标。但这两个因素相互作用的途径尚不清楚。
用蛋白酶体抑制剂 MG-132 处理感染的 PCa 细胞。通过 Western blot 检测 Slug、HA-cyclin D1 和其他蛋白的表达水平。
分别向 DU-145 细胞中加入不同剂量的表达人 Slug 的腺病毒，Slug 和 cyclin D1 的表达均无明显差异。我们发现，高表达 Slug 可使 HA-Cyclin D1（野生型）的蛋白表达均降低，呈剂量依赖性。然而，在携带 pMIGW-Cyclin D1-HA T286A 的 PC-3 中，HA-Cyclin D1（突变型）的表达没有变化。与阴性对照相比，用表达人 Slug 的腺病毒感染携带 pMIGW-Cyclin D1-HA 载体的 PC-3 后，HA-Cyclin D1 的蛋白表达在感染后 3 天均降低，呈剂量依赖性。然而，在经 MG-132 处理的携带 pMIGW-Cyclin D1-HA 的 PC-3 中，HA-Cyclin D1 的表达没有变化。
我们发现，Slug 的强制表达通过下调 cyclin D1 的表达抑制前列腺癌细胞的增殖。Slug 通过泛素蛋白酶体途径调节 PCa 细胞中的 cyclin D1 表达。
