LncRNA MALAT1 modified progression of clear cell kidney carcinoma (KIRC) by regulation of miR-194-5p/ACVR2B signaling

: This investigation was purposed to extrapolate whether and how lncRNA MALAT1, miR-194-5p, and ACVR2B altered development of clear cell kidney carcinoma (KIRC). We totally gathered 318 pairs of KIRC tissues and adjacent normal tissues, and also purchased human KIRC cell lines and normal human proximal tubular epithelial cell line. Besides, si-MALAT1, pcDNA-MALAT1, miR-194-5p mimic, miR-194-5p inhibitor, and negative control (NC) were, respectively, transfected into KIRC cells. The viability, proliferation, and apoptosis of the cells were determined with CCK-8 assay, colony formation assay, and flow cytometry. Dual-luciferase reporter gene assay was implemented to validate the targeted relationships between MALAT1 and miR-194-5p, as well as between miR-194-5p and ACVR2B. The results showed that highly expressed MALAT1, ACVR2B, and lowly expressed miR-194-5p were associated with larger tumor size (≥4 cm), advanced TNM stage and poor prognosis of KIRC patients, when, respectively, compared with lowly expressed MALAT1, ACVR2B, and highly expressed miR-194-5p (P < 0.05). Transfection of pcDNA-MALAT1, miR-194-5p inhibitor, and pcDNA-ACVR2B conferred the KIRC cells with promoted viability and proliferation, as well as reduced apoptosis (P < 0.05). Treatment of rats with pcDNA-MALAT1, miR-194-5p inhibitor, or pcDNA-ACVR2B also contributed to larger tumor size growing in them (P < 0.05). Moreover, MALAT1 could directly target miR-194-5p to suppress its expression, and ACVR2B was the targeted molecule of miR-194-5p (P < 0.05). Finally, ACVR2B could reverse the effects exerted by miR-194-5p on viability, proliferation, and apoptosis of KIRC cells (P < 0.05). In conclusion, LncRNA MALAT1/miR-194-5p/ACVR2B signaling was regarded as a candidate pathway for modulating KIRC progression.