XRCC2 promotes cancer progression by regulating p53/p21 signaling pathway in hepatocellular carcinoma

Abstract

Introduction: X-ray repair cross-complementing gene 2 (XRCC2) plays an important role in DNA damage repair. However, how the expression of XRCC2 was regulated in the progression of hepatocellular carcinoma(HCC) remains unknown. The aim of this study is to investigated the expression of XRCC2 in HCC and to unravel the underlying mechanism of XRCC2 in HCC. Method: The expression of XRCC2 in tissues from HCC patients was analyzed using a microarray and real-time PCR. The effects of XRCC2 on cell proliferation and tumorigenesis in HCC cells were analyzed by flow cytometry, colony formation assays and CCK8 assays. The correlation between XRCC2 expression and long-term outcomes after liver resection, as well as the potential molecular mechanism of XRCC2 in regulating the proliferation in HCC cells were also addressed. Result: The expression of XRCC2 was higher in tumor tissues and HCC cell lines compared to the adjacent liver tissues and normal liver cell lines. The expression level of XRCC2 has a reverse relationship with the long-term outcomes after liver resection. Down-regulating the expression of XRCC2 in HCC cell strains could inhibit the proliferation of HCC cells by inducing S-phase arrest and cell apoptosis in vitro and in vivo. Further study indicates that down-regulating the expression of XRCC2 could induce the up-regulation of p53/p21 signaling pathway. Conclusion: This study provides novel insights into the role of XRCC2 in controlling HCC cell proliferation and tumorigenesis, and identifies XRCC2 as a potential prognostic marker and therapeutic target.