miR-155 Accelerates the Growth of Human Liver Cancer Cells by Activating CDK2 via Targeting H3F3A
Xiaoru Xin, Yanan Lu, Sijie Xie, Ying‐Jie Chen, Xiaoxue Jiang, Shuting Song, Liyan Wang, Pu Hu, Xin Gui, Tianming Li, Jie Xu, Jiao Li, Song Jia, Dongdong Lu
Abstract
miR-155 is associated with the promotion of tumorigenesis. Herein, we indicate that abnormal miR-155 was negatively correlated with the expression of P21WAF1/Cip1. Our results suggest that miR-155 alters the transcriptome and inhibits the expression of H3F3A in liver cancer cells. Therefore, miR-155 inhibits the methylation modification of histone H3 on the 27th lysine. Notably, on the one hand, miR-155-dependent CTCF loops cause the CDK2 interacting with cyclin E in liver cancer cells; on the other hand, miR-155 promotes the phosphorylation modification of CDK2 by inhibiting H3F3A. Subsequently, miR-155 competitively blocks the binding of RNA polymerase II (RNA Pol II) to the P21WAF1/CIP1 promoter by increasing the phosphorylation of CDK2, inhibiting the transcription and translation of P21WAF1/CIP1. Strikingly, excessive P21WAF1/CIP1 abolishes the cancerous function of miR-155. In conclusion, miR-155 can play a positive role in the development of liver cancer and influence a series of gene expression through epigenetic regulation. miR-155 is associated with the promotion of tumorigenesis. Herein, we indicate that abnormal miR-155 was negatively correlated with the expression of P21WAF1/Cip1. Our results suggest that miR-155 alters the transcriptome and inhibits the expression of H3F3A in liver cancer cells. Therefore, miR-155 inhibits the methylation modification of histone H3 on the 27th lysine. Notably, on the one hand, miR-155-dependent CTCF loops cause the CDK2 interacting with cyclin E in liver cancer cells; on the other hand, miR-155 promotes the phosphorylation modification of CDK2 by inhibiting H3F3A. Subsequently, miR-155 competitively blocks the binding of RNA polymerase II (RNA Pol II) to the P21WAF1/CIP1 promoter by increasing the phosphorylation of CDK2, inhibiting the transcription and translation of P21WAF1/CIP1. Strikingly, excessive P21WAF1/CIP1 abolishes the cancerous function of miR-155. In conclusion, miR-155 can play a positive role in the development of liver cancer and influence a series of gene expression through epigenetic regulation.