E3 ubiquitin ligase CHIP attenuates cellular proliferation and invasion abilities in triple-negative breast cancer cells

In this study, the CHIP expression was examined in different human breast cancer cell lines and a group of breast cancer tissues. We found, for the first time, that CHIP expression was correlated with the molecular subtyping of breast cancer. CHIP was least expressed in the base-like subtype of breast cancer, which are triple-negative breast cancer (TNBC) breast cancer predominantly. Accordingly, CHIP expression was evidently decreased in the TNBC MDA-MB-231 breast cancer cell line. Enforced induction of CHIP in the MDA-MB-231 cells exerted no obvious influences on cellular growth and cell cycle. The apoptotic and proliferation cells in hCHIP cells were both reduced compared to the ctrl cells. The mRNA and protein expressions of the anti-apoptotic Bcl-2 and Bcl-xL were markedly increased in the hCHIP cells compared to that of the ctrl cells. The expression of RelA was significantly reduced in the nuclear extract in hCHIP cells compared to that in the ctrl cells. The protein expressions of IKK β were markedly decreased in the hCHIP cells compared to the ctrl cells. The reduced cellular proliferation was largely due to the attenuated IKKβ-p65/NF-κB activity. Meanwhile, the invasion ability but not the migration ability was diminished when CHIP was overexpressed in the MDA-MB-231 cells. The activity of MMP2 but not MMP9 was significantly decreased in the hCHIP cells compared to the ctrl cells. Taken together, these observations here provide functional evidence for CHIP behave...
Source: Clinical and Experimental Medicine - Category: Research Source Type: research