The CircRNA Hsa＿circ＿0102485 Inhibits Prostate Cancer By Regulating The MiR-188-3p/ARID5B/AR Pathway

Objective:Prostate carcinoma(PCa)is one of the most common malignancies in men.There is an urgent need to develop new biomarkers and therapeutic targets for the early screening and treatment of PCa.A large number of studies have shown that circular RNA(CircRNA)has a great application prospect as a molecular marker for tumor diagnosis,treatment and prognosis.Even more and more studies have suggested that CircRNAs,as competing endogenous RNAs(ceRNAs),are involved in the regulation of the occurrence and development of PCa,but the specific role of CircRNAs in PCa is still not fully understood.This study aims to study the role and mechanism of hsa＿circ＿0102485 in PCa,and to clarify the potential of hsa＿circ＿0102485 as a new marker for the diagnosis and treatment of PCa.Methods:(1)To clarify the expression and biological role of hsa＿circ＿0102485 in PCa,The expression of hsa＿circ＿0102485 in prostate cancer tissues and paracancerous tissues,prostate cancer cell lines(PC3,MDA-PCA-2B,DU 145,22RV1,LNCaP)and normal prostate stromal cells(WPMY-1)were detected by real-time quantitative PCR.Then the hsa＿circ＿0102485 knockdown/overexpression cell model was constructed using lentiviral vector.CCK-8 assay was used to detect cell proliferation,scratch test and Transwell assay were used to detect cell migration and invasion,and flow cytometry was used to detect cell apoptosis.(2)In order to explore the mechanism of action of hsa＿circ＿0102485 in PCa,the effects of knockdown/overexpression of hsa＿circ＿0102485 on miR-188-3p,ARID5B and AR expressions were detected by qRT-PCR and Western blotting.The targeting binding relationship of hsa＿circ＿0102485,miR-188-3p and ARID5B was verified by dual luciferase reporter gene assay.The biological role of miR-188-3p in PCa was determined by the recovery experiment.(3)The role of hsa＿circ＿0102485 in the growth of prostate tumors was determined by xenotransplantation test in vivo,and the expression changes of miR-188-3p,ARID5B and AR were detected by qRT-PCR,Western blotting and immunohistochemistry.Finally,the expression of hsa＿circ＿0102485 in PCa tissues and paracancerous tissues was further verified by tissue chip in situ immunohybridization,and the clinical correlation between its expression level and PCa was analyzed.Results:(1)The qRT-PCR results showed that the expression of hsa＿circ＿0102485 was significantly down-regulated in PCa tissues and cell lines compared with that in paracancerous tissues and normal prostate cell lines.Cell function experiments showed that overexpression of hsa＿circ＿0102485 could inhibit the proliferation,metastasis and invasion of MDA-PCA-2B cells,and promote cell apoptosis.(2)The results of qRT-PCR and Western blotting showed that the overexpression of hsa＿circ＿0102485 down-regulated the expression of miR-188-3p,and up-regulated the expression of ARID5B and AR.Dual luciferase reporter gene assay results suggested that hsa＿circ＿0102485 and ARID5B both had specific targeting binding sites with miR-188-3p.The results of the recovery experiment showed that overexpression of miR-188-3p enhanced the proliferation,metastasis,invasion and anti-apoptotic ability of PCa cells,and the co-transfection of miR-188-3p mimics reversed the inhibitory effect of hsa＿circ＿0102485 on PCa cells.(3)Subcutaneous xenograft experiments showed that the overexpression of hsa＿circ＿0102485 in vivo significantly inhibited the growth of prostate tumors,and the interference of hsa＿circ＿0102485 promoted the tumor formation of PCa.The results of RT-qPCR,Western blotting and immunohistochemistry showed that the overexpression of hsa＿circ＿0102485 in vivo significantly inhibited the expression of miR-188-3p and up-regulated the expression of ARID5B and AR.Tissue-chip in situ immunohybridization and analysis of variance showed that the low expression of hsa＿circ＿0102485 in PCa was not significantly correlated with PCa patients’ age,ISUP grade,Gleason score and lymph node metastasis.Conclusion:The hsa＿circ＿0102485 is down-regulated in prostate cancer tissues and cell lines.Overexpression of hsa＿circ＿0102485 inhibited the proliferation,migration and invasion of PCa epithelial cells,while knockdown of hsa＿circ＿0102485 had the opposite effect.Mechanically,hsa＿circ＿0102485 uninhibited ARID5B by adsorbing miR-188-3p in sponge and promoted AR expression,thereby inhibiting the proliferation,invasion,metastasis and anti-apoptotic ability of PCa epithelial cells.We confirmed for the first time the antitumor effect of hsa＿circ＿0102485 in PCa,providing a new theoretical basis for the development of novel diagnostic markers and therapeutic targets for PCa.