Histone Acetyltransferase P300 And Mrtf-a Synergistically Promote The Migration Of Breast Cancer Cells

Tumor metastasis is the leading cause of breast cancer death,while invasion and migration of cancer cells is an important step of the metastatic processes.Migration is a complex biological process,which associated with a variety of signaling pathways and transcription factors.Now as we know,there are hundreds of genes that are related to tumor cells migration,therefore the research work should focus on exploration of the key molecules and genes that affect the expression of dozens,even hundreds of target genes.p300 is an important member of histone acetytransferases family,which is widely involved in a series of gene regulation.It has been reported that high expression of p300 in breast cancer was positively correlated with tumor recurrence and adverse prognosis but it has not been reported in the field of breast cancer metastasis up to now.Recent data showed that MRTF-A had a significant effect on the migration of breast cancer cells.Here we want to study the function of p300 and whether there is a synergic effect between p300 and MRTF-A on the migration of breast cancer.First,we used wound healing assay to investigate the role of p300 in breast cancer cell migration.The results proved that p300 can promote the migration of breast cancer cells MCF-7 and MDA-MB-231.And the analyses of RT-RCR,Real-time PCR,western blotting and luciferase report gene activity assay showed that p300 can raise the transcription and expression of migration-related genes,and exhibited a dose-dependent relationship;p300-specific siRNA was transfected into cells to inhibit the p300 gene expression,we found that it can significantly reduce the migration of the both cancer cells and the mRNA and protein levels of migration-related genes in p300 depleted MCF-7 cells.Next,we explored whether p300 and MRTF-A could synergically promote breast cancer cell migration.First,MRTF-A expression was knocked down with specific shRNA and the results showed that both the mRNA levels and protein levels of migration-related genes were reduced.Here,our results supported the metastasis-promoting roles of MRTF-A as some studies demonstrated.Then,we overexpressed p300 and MRTF-A in MCF-7 cells and detected the changes of transcription and expression of migration-related genes before and after transfection through the analyses of RT-PCR,Real-time PCR and western blotting.We found both the transcriptional level and the expression level have a remarkablely upregulation after single transfection or cotransfection,and shows obvious synergy between p300 and MRTF-A.Finally,we studyed the molecular mechanisms of p300 and MRTF-A synergically promoting breast cancer cell migration.First of all,in order to determine whether the synergy of p300 and MRTF-A resulted from a direct interaction between the proteins,we performed coimmunoprecipitation assays with MRTF-A truncated mutants.The data...