LncRNA RP11-462C24.1 Regulates The Proliferation Apoptosis And Migration Of Colorectal Cells Via HSP70/PI3K/AKT Signal Pathway

Background:Colorectal cancer is a malignant tumor that seriously endangers human’s health.The pathogenesis of colorectal cancer remains unclear.LncRNA is a research hotspot in recent years and participates in many kinds of disease processes and plays an important role in the pathogenesis of cancer.Currently,the study of expression and significance for LncRNA in colorectal cancer is still limited.Therefore,it is of great significance to further study the expression and function of LncRNA in colorectal cancer.Methods:We compared the expression of RP11-462C24.1 in 60 CRC tumor samples and 60 adjacent tissues using RT-qPCR method.Then we analyzed the correlation between the levels of RP11-462C24.1 and the clinical characteristics of patients.SW480 and HT-29 cell lines were used in the following in vitro and in vivo studies.Transient over-expression and knockdown of RP11-462C24.1 in SW480 and HT-29,then we detected cell proliferation by CCK8 assays,the cell apoptosis by flow cytometry,the ability of cell migration by transwell assays.After transfection of RP11-462C24.1 over-expression plasmid and siRNA,we investigated the expression of RPL34,HSP70 and PI3K/AKT related proteins by western blotting.Add AKT-inhibitor MK-2206 to knockdown of RP11-462C24.1 cells to do regression testing process.Add over-expression HSP70 to over-expression RP11-462C24.1 cells to do regression testing process.RP11-462C24.1 over-expression plasmid transfected SW480 cell line and un-transfected cell line were subcutaneously implanted into nude mice.We established the xenograft mice tumor models to evaluate the effect of RP11-462C24.1 on the tumorigenesis of SW480 cell line in vivo.Results:We compared the expression of RP11-462C24.1 in 60 CRC tumor samples and 60 adjacent tissues,the results shown that RP11-462C24.1 was significantly down-regulated in CRC tumor samples compared with the adjacent tissues,and the level of RP11-462C24.1 in patients with CRC was negatively correlated with the TNM stage and metastasis of the patients.We also observed that RP11-462C24.1 was significantly down-regulated in CRC cell lines compared with the control cell line.To further investigate the role of RP11-462C24.1 in the pathogenesis of CRC,we tested the effect of RP11-462C24.1 on the proliferation and apoptosis in SW480 and HT-29 cell lines,the results shown that RP11-462C24.1 significant decreased the proliferation and increased the apoptosis both in SW480 and HT-29 cell lines.Over-expression of RP11-462C24.1 markedly decreased the migratory ability of SW480 and HT-29 cell lines,on the other hand,transfection of RP11-462C24.1 siRNA has led to increase migratory ability of SW480 and HT-29 cell lines in vitro.Our research also found that RP11-462C24.1 regulated the proliferation and apoptosis of SW480 and HT-29 cell lines through regulating the expression of RPL34,HSP70 and PI3K/AKT signal pathway in vitro.Affirmed by regression testing process.In addition,in vivo studies indicated that RP11-462C24.1 inhibited tumor growth compared with the control in tumor xenograft models.These results will widen our understanding of the mechanisms of the pathogenesis of colorectal cancer,and help to provide new targets for prophylactic and therapeutic strategies for colorectal cancer.Conclusion:The expression of RP11-462C24.1 in CRC tissue samples was significantly down-regulated.RP11-462C24.1 decreased the proliferation and increased the apoptosis of CRC cells.RP11-462C24.1 inhibited the migratory ability in CRC cells in vitro.RP11-462C24.1 may regulates the proliferation and apoptosis through regulating the RPL34 and HSP70/PI3K/AKT signal pathway.RP11-462C24.1 inhibited tumor growth compared with the control in tumor xenograft models and functioned as a tumor suppressor.