The Relationship Between Single Nucleotide Polymorphism At MiR502 Binding Sites And The Expression Of SET8 And The Outcome Of Renal Clear Cell Carcinoma Patient

Objective: It’s reported that more than 350,000 people diagnosed with renal cell carcinoma worldwide each year,and this cancer is associated with more than 140 000 deaths per year.Renal clear cell carcinoma is the common pathological type of RCC,accounted for about 60% of all patients with RCC.Until now,the main treatment for clear cell renal cell carcinoma(ccRCC)is resection,and ccRCC is highly resistant to chemotherapy.As well as approximately 30% patients of ccRCC who have distant metastases at the time of diagnosis.Above all significantly limits the postoperative survival rate of patients with ccRCC.MicroRNAs(miRNA)is a kind of highly conservative small non-coding RNA,which regulates the expression of target genes by binding to the 3’-UTR of mRNA in nocoding region leading to degrade or inhibit its translation.More and more studies have shown that genetic mutation in the 3’-UTR of mRNA may affect oncogenesis by changing the miRNA-mRNA binding force and miRNA-targeted gene expression.SET8 functions as a monomethylation catalyst for histone H4K20.Previous studies showed that SET8 may possess various functions in many biological processes,including the maintenance of genome integrity,regulation of gene transcription,mediation of DNA repair and damage,and the control of cell-cycle progression and development.Several studies reported that single nucleotide polymorphism at miR502 binding sites in SET8 mRNA is related to the oncogenesis,such as hepatocellular carcinoma and breast cancer.Especially the expression of SET8 in tumor tissue was obviously higher than that of adjacent non tumor tissues,which closely related with the prognosis of tumor.The aim of this study is to explore the relationship between single nucleotide polymorphism at miR-502 binding sites and the expression of SET8 and the outcome of clear cell renal cell carcinoma,and observe the change in biology of 786-O cell by knowdown of endogenous expression of SET8.Methods:1 A total of 110 patients diagnosis with ccRCC in the Department of Urology Pathology in the Fourth Hospital of Hebei Medical University from January 2006 to December 2010 were enrolled.Demographic characteristics and clinical information were collected from medical records.The clinical information included sex,age at diagnosis,TNM stage,tumor size,and lymph node metastasis.We followed up these patients until December 2015 through recheck and regular telephone.Moreover a total of 130 healthy people without diseases associated with renal clear cell carcinoma and taking physical examination in the Fourth Hospital of Hebei Medical University from October 2012 to October 2013 were enrolled.Detailed clinical information and blood were collected.2 Gene sequencing detected the genotype of miR502 binding site,and analysis the relation between the risk and outcome of ccRCC and genotype.The relationship between the expression of SET8 and the clinical information and outcome of ccRCC was analysized by immunohistochemistry.3 The clear cell renal cell carcinoma cell line 786-O cells were divided into three groups: Control(without transfection),NS-siRNA(transfected with negative sh RNA),SET8-siRNA(transfected with positive sh RNA).The proliferation of 7860-O cells were determined by MTT and clone formation.The migration was determined by wound healing assay,and the cell invasion was determined by transwell invasion assays.The expression of Survivin,Caspase3,and E-cadhrin by qPCR and Western Blot.Results: We provide evidence that the SET8 CC genotype was associated with a decreased risk of renal cell cancer(RCC)in this case-control study.Furthermore,we found that the SET8 CC genotype was associated with reduced SET8 protein levels based on the immunostaining of 110 RCC tissue samples.We also found that low SET8 levels were associated with longer RCC survival rates.SET8 knockdown inhibited the proliferation,migration,and invasion of 786-O renal cancer cells.The expression of Caspase3 and E-cadherin were up-regulated,while Survivin expression was down-regulated by SET8 knockdown in 786-O renal cancer cells.Conclusion:1 CT and TT genotypes of miR502 binding sites in the 3’UTR of SET8 mRNA are associated with the elevated risk of ccRCC.2 CT and TT genotypes of miR502 binding sites in the 3’-UTR of SET8 mRNA are relation to the high expression of SET8,and SET8 is an independent risk factor for the five-year prognosis of patients with renal cell carcinoma.3 SET8 may regulate the proliferation,apoptosis,invasion,and metastasis of 786-O cell by Survivin,Caspase3 and E-cadherin.4 Analyzing the single nucleotide polymorphism of miR502 binding sites in the 3’UTR of SET8 mRNA and the expression of SET8 will help us identify high risk people of ccRCC.