Downregulated PIRH2 Can Decrease the Proliferation of Breast Cancer Cells

Background and Aims. We undertook this study to investigate the influence of PIRH2 (p53-induced RING-H2) protein on the proliferation and cell cycle of breast cancer cell lines. Methods. PIRH2 expression was detected by Western blot analysis, immunohistochemistry (IHC) and Kaplan-Meier curve analysis. Cell proliferation was assessed by cell counting kit-8 (CCK-8). Cell cycle control was analyzed by flow cytometry. Results. PIRH2 was up-regulated in breast cancer tissues and cell lines and up-regulated PIRH2 was highly associated with tumor size, grade, ER, and Ki-67. Moreover, Kaplan-Meier curve showed that up-regulated PIRH2 was related to the poor overall survival of patients with breast carcinoma. When the expression of PIRH2 was inhibited by siRNA transfection, cell proliferation was reduced. In addition, the number of G0/G1 phase cells was increased, but G2/M cells were not affected significantly. Conclusion. Decrease of PIRH2 expression in the breast cancer cell line MDA-MB-231 resulted in reduced tumor cell growth via the inhibition of cell proliferation and the interruption of cell cycle transition. (C) 2016 IMSS. Published by Elsevier Inc.