The Role And Mechanism Of HAPLN3 In The Development And Progression Of Clear Cell Renal Cell Carcinoma

Background:Hyaluronan and proteoglycan link protein 3(HAPLN3)are the members of Hyaluronan and proteoglycan link protein family in extracellular matrix.Early studies have shown that HAPLN3 may be closely related to the occurrence and development of a variety of malignant tumors.However,the role and mechanism of HAPLN3 in clear cell renal cell carcinoma(ccRCC)have not been reported.In this study,we identified HAPLN3 as a potential new gene of clear cell renal cell carcinoma based on bioinformatics analysis,aiming to explore the influence and mechanism of HAPLN3 on the progression of clear cell renal cell carcinoma.Methods:Firstly,we investigated the differences of HAPLN3 expression in ccRCC by analyzing the data sets from the Cancer Genome Atlas(TCGA)and Gene Expression Synthesis(GEO)databases,and further validated them in the Human Protein Atlas(HPA)database.TCGA data set was used to analyze the correlation between HAPLN3 expression level and ccRCC progression and its prognostic value in ccRCC.Gene enrichment analysis(GSEA)was used to explore the related signaling pathways of HAPLN3 in ccRCC.Then,in order to investigate the biological function of HAPLN3 in ccRCC,a series of in vitro experiments were carried out to verify the expression level of HAPLN3 in different cell lines and tissue samples by real-time fluorescence quantitative PCR(QRT-PCR)and western blot(WB).HAPLN3 gene was knocked down by small interfering RNA transfection.Proliferation,apoptosis,migration and invasion of tumor cells were detected by CCK-8,EdU,flow cytometry and Transwell chamber invasion assay.Result:In this study,we found that HAPLN3 was overexpressed in ccRCC,and the expression level of HAPLN3 was related to the survival time and clinicopathological parameters of tumor patients.Meanwhile,HAPLN3 is an independent risk factor for ccRCC patients.In addition,siRNA knockdown of HAPLN3 can inhibit the proliferation,migration and invasion of ccRCC cells and promote the apoptosis of tumor cells in vitro.Further studies showed that HAPLN3 knockdown increased the protein expression of Bax and E-cadherin,and decreased the protein expression of Bcl-2,PARP,N-cadherin,MMP-2,Vimentin and p-Erk1/2.Conclusion:The results showed that HAPLN3 was abnormally high in the progression of ccRCC,and could regulate the proliferation,apoptosis,migration and invasion of ccRCC cells by activating the ERK1/2 signaling pathway.Therefore,HAPLN3 can be used as a new potential biomarker and therapeutic target in ccRCC.