Wilms' Tumor 1 Associated Protein Promotes Renal Cell Carcinoma Proliferation By Regulating CDK2 Stability

Objective:Wilms' tumor 1-associating protein(WTAP)plays an important role in the normal physiological processes of human and the development of tumor,but its specific biological role and related mechanism in renal cell cancer(RCC)remain unknown.The aims of this study were to investigate the expression of WTAP in RCC and explore its function in RCC cell lines.Methods:Quantitative real-time PCR and western blot were used to detect the expression level of WTAP in both human RCC cell lines and tissues.Immunohistochemistry and survival analysis were adopted to explore the association between WTAP expression and the prognosis of RCC.RCC cells were stably transfected with lentivirus approach and cell proliferation,migration,invasion,as well as tumorigenesis in nude mice were performed to assess the effect of WTAP in RCC.RCC cell lines were treated with actinomycin D and CDK2 1RNA expression was detected to explore the relationship of WTAP and the stability of CDK2 mRNA.To analysis whether there was an association between WTAP and CDK2,RNA immunoprecipitation(RIP)and dual-luciferase reporter assays were performed.Results:The results of qRT-PCR and and Western Blot showed that WTAP was significantly overexpressed in renal cell lines and tissues.Compared with patients with low expression of WTAP,patients with high expression of WTAP had higher grade of tumor stage,larger tumor size and lower overall survival rate.Additionally,cell function test in Caki-1 and ACHN indicated that cell proliferation,migration and invasion abilities in WTAP over-expressed group were enhanced compared with the negative control group,while WTAP knockdown showed the opposite results.Subcutaneous xenograft tumor model displayed that knockdown of WTAP could impede tumorigenesis in vivo.Mechanism study exhibited that WTAP overexperssion could increase the stability of CDK2 mRNA,while knockdown of WTAP decrease it.WTAP could bind to the 3'-UTR of CDK2.Conclusion:In conclusion,these findings suggest that WTAP may have an oncogenic role in RCC through physically binding to CDK2 transcript and enhancing its stability.Our study might provide new insights into RCC therapy and WTAP research.