The Role Of CtBP2-c-Myc Signaling In The Prostate Cancer Progression

Objective:To reveal the mechanism of Ct BP2-c-Myc signaling in regulating prostate cancer cell biological behaviour.Methods:The Ct BP2 c DNA was intercepted the sequence via genetic engineering and Ct BP2 high expression of recombinant plasmids were obtained. The plasmids were transformed into PC3 cells. RT-q PCR and Westernblot were used to identify the level of Ct BP2 expression.The proliferation of Ct BP2 high expressed PC3 cells and normal PC3 cells were assessed by MTT assay.The ability of migration and invasion was assessed by Transwell between Ct BP2 high expressed PC3 cells and normal PC3 cells,and also Annexin V assay was used to evaluate apoptosis. RT-q PCR and Westernblot were used to detect the influence of Ct BP2 high expression to m RNA expression of Rho A、Rho B and Rho C. We queried UCSC database, and predicted whether or not Ct BP2 transcriptionally regulated Rho C. Plasmids containing Ct BP2 combined with Rho C transcription areas of DNA were built.Detecting whether Ct BP2 potentially transcriptional regulated Rho C by luciferase and chip assay. Rho C high/low expressed PC3 cells were verified by RT-q PCR assay, ROCK kinase activity was detected. Westernblot was used to detect the protein expression of p-MLC in Rho C high/low expressed PC3 cells. Westernblot was also used to detect the protein expression of ROCK1,Rho C, c-Myc, p-c-Myc and HSPC111 when Ct BP2 was high expressed.Results:1. Ct BP2 high expressed PC3 cells were successfully built, RT-q PCR and Westernblot were used to verify the high level of Ct BP2 expression(P<0.001);2. Cell biological behaviour tests showed that overexpression of Ct BP2 in PC3 cells improved cell invasion(P<0.05) but not proliferation(P>0.05)and apopotosis(P>0.05);3. We found that high expression of Ct BP2 promoted the m RNA expression of Rho A(P<0.05) and Rho C(P<0.001), but restrained Rho B m RNA expression(P<0.01);4. We queried UCSC database, and predicted that Ct BP2 transcriptionally regulated Rho C. Plasmids containing Ct BP2 combined with Rho C transcription areas of DNA were built successfully.It was found that Ct BP2 potentially transcriptionally regulated Rho C by luciferase and chip assay.5. Rho C high/low expressed PC3 cells were verified by RT-q PCR assay successfully. We found that high expression of Rho C promoted ROCK kinase activity(P < 0.005), low expression of Rho C inhibited ROCK kinase activity(P < 0.005). The protein expression of p-MLC in Rho C high expressed PC3 cells was enhanced, but it was decreased in Rho C low expressed PC3 cells. When Ct BP2 was high expressed, the protein expression of ROCK1,Rho C, c-Myc, p-c-Myc and HSPC111 were enhanced(P<0.001).Conclusions:Overexpression of Ct BP2 in PC3 cells improves cell invasion. Ct BP2 can regulate c-Myc and promote the progress of prostate cancer. Ct BP2 is proved to be a new target to the treatment of prostate cancer.