Ribosomal Protein L11 Affects The Progression Of Renal Clear Cell Carcinoma Cells By Inhibiting The Activity Of The C-Myc Promoter

Objective: The aim of this study is to explore the impact and mechanism of ribosomal protein L11(RPL11)on multiple biological functions of clear cell renal cell carcinoma(cc RCC)cells,such as proliferation,cell cycle,apoptosis and migration.Methods:(1)Bioinformatics.Based on The Cancer Genome Atlas(TCGA)database for cancer genomics and using the R language to analyze the relationship between RPL11 and the survival period of patients with clear cell renal cell carcinoma.Using the GEPIA database to analyze the expression of c-Myc in clear cell renal cell carcinoma samples.(2)Cell biology and molecular biology.The expression of RPL11 in cc RCC cell lines(786-O and Caki-1)was analyzed by q RT-PCR and Western Blotting.An overexpression plasmid of RPL11 was synthesized and transfected into cc RCC cell lines to investigate the biological functions of RPL11 on cc RCC through MTT,colony formation,flow cytometry,cell scratch and Transwell assays.The effect of RPL11 on the expression of c-Myc and its downstream target genes was detected by q RT-PCR and Western Blotting experiments.An overexpression plasmid of c-Myc was synthesized and co-transfected with the overexpression plasmid of RPL11 into cc RCC cell lines.MTT,colony formation,cell scratch,and Transwell assays were performed to determine if overexpressing c-Myc can reverse the effects of overexpressing RPL11 on the biological functions of cc RCC cells.The binding of RPL11 to the c-Myc promoter region was validated by a luciferase reporter gene experiment.Results:The TCGA database was analyzed to study cc RCC clinical non-paired samples and compared with normal samples.It was found that RPL11 is positively correlated with poor survival in tumor samples.q RT-PCR and Western blotting detected that RPL11 expression was downregulated in cc RCC cell lines.Overexpression of RPL11 inhibited the proliferation of cc RCC cells,arrested the cell cycle in the G0/G1 phase,increased apoptosis,and inhibited cell migration.Western blotting detected that overexpression of RPL11 can arrest the cell cycle in the G0/G1 phase by downregulating CDK4.RPL11 can promote apoptosis by upregulating Bak and downregulating Bcl-2 and Bcl-x L.RPL11 can inhibit cell migration by upregulating E-cadherin and downregulating MMP2,MMP9,and N-cadherin.These results suggest that RPL11 inhibits the progression of cc RCC.Further experiments with a luciferase reporter gene showed that RPL11 binds to the c-Myc promoter region and has a negative regulatory effect.Specifically,overexpression of RPL11 can inhibit the expression of c-Myc m RNA and protein,as well as downstream target gene m RNA expression.Conclusion:RPL11 is down-regulated in cc RCC cell lines and has an inhibitory effect on the proliferation and migration of cc RCC cells.As a tumor suppressor gene,RPL11 inhibits the expression of c-Myc by binding to its promoter region,thereby inhibiting cc RCC cell proliferation,cell cycle G0/G1 phase transition,and migration,while promoting cell apoptosis.