MCM3AP-AS1 KD Inhibits Proliferation, Invasion, and Migration of PCa Cells via DNMT1/DNMT3 (A/B) Methylation-Mediated Upregulation of NPY1R

Prostate cancer (PCa) is a heterogeneous tumor that commonly occurs among males worldwide. This study explored the potential role that long non-coding RNA MCM3AP antisense RNA 1 (MCM3AP-AS1) plays in PCa progression, and investigated its mechanism. MCM3AP-AS1 and neuropeptide Y receptor Y1 (NPY1R) expression was determined in PCa cells. The regulatory role of MCM3AP-AS1 in PCa cells was defined using scratch test, Transwell assay, 5-ethynyl-2′-deoxyuridine (EdU) assay, and flow cytometry. Methylation-specific PCR (MSP) was used to test the methylation level of NPY1R. Subsequently, the interaction among MCM3AP-AS1, DNA methyltransferase (DNMT)1/DNMT3 (A/B), and NPY1R was investigated using RNA immunoprecipitation, RNA pull-down, and chromatin immunoprecipitation. Finally, we observed xenograft tumor in nude mice. MCM3AP-AS1 was highly, whereas NPY1R was poorly, expressed in PCa. Lentivirus-mediated overexpression of MCM3AP-AS1 promoted proliferation, invasion, and migration while suppressing apoptosis of PCa cells, whereas opposite trends were detected after inhibition of the mitogen-activated protein kinase (MAPK) pathway. MCM3AP-AS1 promoted methylation of NPY1R promoter via recruitment of DNMT1/DNMT3 (A/B), thereby downregulating NPY1R expression to activate the MAPK pathway. Furthermore, overexpressed MCM3AP-AS1 was observed to facilitate PCa development in vivo, which could be reversed by overexpressed NPY1R. Altogether, MCM3AP-AS1 silencing inhibits PCa progression by disrupting methylation of the NPY1R promoter to inactivate the MAPK pathway.