LncRNA MYMLR promotes pituitary adenoma development by upregulating carbonyl reductase 1 via sponging miR-197-3p.

Abstract

Long noncoding RNAs (lncRNAs) have been demonstrated to participate in various biological processes and play key roles in tumorigenesis and metastasis. Pituitary adenoma (PA) is one of the most common malignancies in central nervous system. Recently, multiple lncRNAs have been identified to regulate PA initiation, progression and metastasis. we aimed to elucidate the expression pattern and function of lncRNA MYMLR in PA development. The expression of lncRNA MYMLR in PA tissues and cells was examined by real-time quantitative PCR. Knockdown of MYMLR expression was achieved by using shRNA. The function of MYMLR and regulatory network were analyzed using CCK-8 assay, wound-healing assay, migration assay and Annexin V/PI staining. Xenograft tumor model was used to explore the function of MYMLR in vivo . Bioinformatics analysis and luciferase reporter assay were conducted to investigate the interaction between MYMLR and its regulatory network. LncRNA MYMLR was highly expressed in PA tissues compared with that in normal tissues. Knockdown of MYMLR suppressed cell proliferation, migration and invasion, while promoting PA cell apoptosis. Mechanistically, MYMLR functioned as a competing endogenous RNA (ceRNA) sponging microRNA miR-197-3p. Furthermore, miR-197-3p exerted its tumor inhibitory role via negatively regulating carbonyl reductase 1 (CBR1). Overexpression of CBR1 antagonized the inhibitory effect of lncRNA MYMLR knockdown or miR-197-3p overexpression. In addition, xenograft tumor model revealed that knockdown of lncRNA MYMLR suppressed PA tumor development in vivo via regulating CBR1. Our findings suggest a regulatory network of lncRNA MYMLR/miR-197-3p/CBR1, which benefits the understanding of PA development and provides a promising lncRNA-direct therapeutic strategy against PA.