Downregulation of circ-PSMB6 suppresses NSCLC progression and metastasis through sponging miR-532-5p and regulating EZH1 expression
Abstract Background: Accumulating reports showed how circular RNAs (circRNAs) act importantly during tumor progression via regulating gene expression, but regulatory mechanisms remain largely unknown. Current investigation clarified circRNA regulatory mechanisms in non-small cell lung cancer (NSCLC).Methods: High-throughput sequencing and quantitative reverse transcription polymerase chain reaction (RT-qPCR) detection were utilized to explore circRNA expression in NSCLC tissues and cells. Our lab did statistical analyses and luciferase reporter analysis to validate correlations between circRNA, miRNA and gene expression. We transfected NSCLC cells with different vectors, and transwell migration, Cell Counting Kit-8 (CCK-8) proliferation along with colony formation assays were performed. In vivo tumorigenesis and metastasis assays were utilized to validate the circRNA role in NSCLC.Results: Data illustrated that hsa_circ_0041595 (circ-PSMB6) incremented in NSCLC cell lines and tissues, while circ-PSMB6 downregulation suppressed NSCLC cell proliferation and invasion in vitro and in vivo. Bioinformatics analysis and luciferase reporter data verified that miR-532-5p and Enhancer Of Zeste 1 Polycomb Repressive Complex 2 Subunit (EZH1) were circ-PSMB6 downstream targets in NSCLC cells. Overexpression of EZH1 or miR-532-5p inhibition reversed NSCLC cell invasion and proliferation after silencing circ-PSMB6. Further experiments discovered that circ-PSMB6 can influence cancer stem cell differentiation by regulating miR-532-5p/EZH1.Conclusions: Taken together, we found that circ-PSMB6 suppressed NSCLC metastasis and progression via sponging miR-532-5p and regulating EZH1 expression.