RASSF10 is Epigenetically Inactivated and Suppresses Cell Proliferation and Induces Cell Apoptosis by Activating the p53 Signalling Pathway in Papillary Thyroid Carcinoma Cancer

Abstract

Objectives: We aimed to confirm whether RASSF10 activated the p53 signalling pathway, thereby modulating cell proliferation, migration, invasion, and apoptosis in papillary thyroid carcinoma (PTC) cells. Methods: A total of 108 PTC tissue samples and normal adjacent tissues were obtained. RT-PCR and Western blotting analyses were performed to detect RASSF10 expression, and methylation levels of RASSF10 were estimated by methylation-specific PCR (MSP). We also detected the expression and methylation status of RASSF10 in both a human PTC cell line (K1) and a normal thyroid cell line (FRTL5). After transfection of cells with empty vector pcDNA3.1, pcDNA3.1-RASSF10, p53 siRNA and shRASSF10, Coulter counter, colony-formation, wound healing, Transwell and flow cytometry analyses were performed to examine the role of RASSF10 in cell proliferation, migration, invasion, and apoptosis. Finally, the expression of p53, p21, Bcl-2 and Bax were detected using Western Blotting analyses. Results: RASSF10 expression in PTC tissues was significantly lower and hyper-methylated compared to normal adjacent tissues. In addition, RASSF10 was significantly down-regulated and hyper-methylated in K1 cells compared to FRTL5 cells. In addition, suppressed proliferation and significantly induced apoptosis of K1 cells were observed after transfection with pcDNA3.1-RASSF10 (P < 0.05). Furthermore, RASSF10 activated the p53 signalling pathway and regulated the expression of p53, p21, Bcl-2 and Bax. Furthermore, p53 siRNA could antagonize the effects of RASSF10 in K1 cells. Conclusions: RASSF10 induces apoptosis in PTC cells by activating the p53 signalling pathway, indicating its role as a treatment target for PTC.