| Summary: | Objective To demonstrate the role of protease activated receptor 2 (PAR2) in the proliferation and apoptosis of hepatocellular carcinoma (HCC) cells. Methods Firstly, the mRNA expression level of PAR2 in the cancer and para-cancerous tissues of 100 HCC patients were detected by RT-qPCR. Then the association between multiple clinicopathologic parameters and PAR2 mRNA level in HCC tissues were illustrated by statistical analysis. Secondly, the mRNA and protein levels of PAR2 in primary hepatocyte (PHH cells), immortalized hepatocyte (MIHA cells) and hepatoma cell lines (PLC/PRF/5, SK-Hep-1, HepG2 and Hep3B) were determined by RT-qPCR and Western blotting. Thirdly, the proliferation of HCC cells was analyzed by MTS and soft agar assay after the silence of PAR2. Moreover, the apoptosis of HCC cells was analyzed by flow cytometry and the cleavage of PARP after the silence of PAR2. Finally, the apoptosis target genes were screened by RT-qPCR, and then validated by Western blotting. Results The relative mRNA level of PAR2 was 1.86±1.26 in HCC tissues, which was significantly higher than that in the adjacent tissues (0.96±0.66, P < 0.001), and the up-regulation of PAR2 in HCC tissues was positively correlated with tumor size and tumor stage (P=0.002). Also, the expression level of PAR2 in hepatoma cell lines was significantly higher than those in immortalized hepatocytes and primary hepatocytes (P < 0.05). Importantly, silence of PAR2 inhibited the cell viability and colony forming ability in SK-Hep-1 and PLC/PRF/5 cells (both P < 0.01), and also induced the apoptotic rate increased to 109% and 112% in SK-Hep-1 and PLC/PRF/5 cells (P < 0.01), separately. What's more, the silence of PAR2 up-regulate the expression of Bax at mRNA and protein levels. Conclusion PAR2 affects the proliferation and apoptosis of HCC cells through regulating the expression of Bax.
|
|---|
