Abstract:
Purpose：Clusterin (CLU), also known as apolipoprotein J, has two isoforms: secretory CLU protein (sCLU) and nuclear CLU protein (nCLU), and the former is now increasingly found to be closely related with the tumorigenesis. Nowadays, more and more studies reported that, especially in bladder cancer, sCLU is involved in chemotherapeutic resistance and result in bad prognosis. However, little has been known about the mechanism of how the sCLU regulates the tumorigenesis of bladder cancer (BCA) up to now. Here, the molecular mechanism of sCLU in BCA was explored. Methods: We collected 16 pairs of bladder cancer tissues samples, and identified that the expression level of sCLU with PT-PCR. Down-regulation of sCLU by small interfering RNA (si-RNA) was transfected in BCA cell lines. 48h after transfected, we took cell proliferation, colony formation assay to evaluate the effect on the biological characters of tumor cells. What’s more, western blot was used to determine MAKPs signaling, such as P38，JNK, ERK, was also detected. Results: sCLU has a high level expression in human BCA tissues. Knocking down the gene clusterin, the BCA cell lines had a lower cell proliferation abilities（p<0.05）. Via down regulation of MAPK/P38 signal pathway, the BCA cell lines had a poor cell proliferation compared with the negative group. Conclusion: Our findings demonstrated that silence of gene clusterin effectively inhibits the proliferation through MAPK/P38 signal pathway.