The long noncoding RNA MIR4435-2HG enhances the migration, promotion, and glycolysis of nonsmall cell lung cancer cells by targeting the miR-371a-5p/SOX2/PI3K/Akt axis

Abstract

Background: Nonsmall cell lung cancer is a leading cause of cancer-related death worldwide. The long noncoding RNA MIR4435-2HG has been shown to play a carcinogenic role in various cancers. The purpose of this study was to explore the role and regulatory mechanism of MIR4435-2HG in non-small cell lung cancer. Methods: Quantitative real-time polymerase chain reaction was used to detect MIR4435-2HG and SRY-box transcription factor 2 in nonsmall cell lung cancer cells. Gain- or loss-of-function assays of MIR4435-2HG and SRY-box transcription factor 2 were subsequently conducted. Cell proliferation, apoptosis, migration, glycolysis, and invasion were tested. A nude mouse tumor model was constructed to determine the role of MIR4435-2HG and SRY-box transcription factor 2 in the growth of tumor cells in vivo. Furthermore, the interactions between MIR4435-2HG, miR-371a-5p and SRY-box transcription factor 2 were analyzed via a dual-luciferase reporter gene assay. Results: Quantitative real-time polymerase chain reaction revealed that MIR4435-2HG and SRY-box transcription factor 2 were upregulated in nonsmall cell lung cancer cells. Forced MIR4435-2HG overexpression led to increased cell proliferation, migration, invasion, and glycolysis and repressed cell apoptosis. Overexpressing MIR4435-2HG promoted SRY-box transcription factor 2 expression and PI3K/Akt/mTOR pathway activation. Downregulating MIR4435-2HG had antitumor effects both in vitro and in vivo. SRY-box transcription factor 2 overexpression mostly reversed the suppressive effects of MIR4435-2HG downregulation. Mechanistic studies revealed that MIR4435-2HG, a competitive endogenous RNA, directly targeted and inhibited miR-371a-5p. Rescue assays revealed that miR-371a-5p overexpression or SRY-box transcription factor 2 downregulation significantly inhibited MIR4435-2HG-mediated oncogenic effects. Conclusion: MIR4435-2HG promotes nonsmall cell lung cancer cell malignant behaviors and glycolysis by regulating the miR-371a-5p/SOX2 axis.