[Study on Cep63 expression and apoptosis of thyroid papillary carcinoma cell lines TPC-1]

Objective: To investigate the effect of centrosomal protein Cep63 on the apoptosis of papillary thyroid carcinoma (PTC) cell lines TPC-1 and underlying mechanism. Methods: With collected PTC tissues and adjacent tissues, Cep63 expression was detected by RT-qPCR and its relationship with clinicopathological factors was analyzed. The experiment included negative control group (NC), low expression group (Cep63(-)) and overexpression group (Cep63(+)), and wild-type TPC-1 cells were transfected with Cep63 lentivirus. The efficiency of Cep63 was detected by western blot (WB) and qRT-PCR. Cell proliferation ability was detected by plate cloning experiment and MTT assay. Cell apoptotic rate was detected by flow cytometry, and expression levels of apoptosis-related proteins were detected by immunohistochemistry and WB. The t-test was used to compare the differences in the means between the two groups, the one-way analysis of variance was used to compare multiple groups, and the chi-square test was used to analyze the association between gene expression levels and pathological factors. Results: Compared with NC group, cell proliferation ability was significantly decreased in Cep63(-) group (3.18±0.07 vs. 2.14±0.09, t=8.54, P<0.01) and significantly increased in Cep63(+) group (3.18±0.07 vs. 3.58±0.10, t=3.21, P<0.05). Apoptotic rates in NC, Cep63 (-) and Cep63 (+) groups were respectively 3.03%±0.24%, 8.66%±0.44% and 1.17%±0.44%, and the flow cytometry showed that the low expression of Cep63 significantly increased the apoptosis TPC-1 cells (F=157.7, P<0.001). Bcl-2 protein expression levels of NC, Cep63 (-) and Cep63 (+) groups were respectively 1.07±0.03, 0.49±0.01 and 1.99±0.09, and BAX protein expression levels of three groups were respectively 0.64±0.02, 1.06±0.01 and 0.21±0.03. WB showed that the expression level of Bcl-2 decreased (F=183.2, P<0.001), while the expression level of BAX was significantly up-regulated (F=283.7, P<0.001). Conclusion: Cep63 may regulate the apoptotic process of TPC-1 cells through Bcl-2/BAX pathway and Cep63 may be a potential oncogene of PTC.