LINC00638 promotes the progression of non-small cell lung cancer by regulating the miR-541-3p/IRS1/PI3K/Akt axis

Background: Preceding works reveal the function of long non-coding RNAs (abbreviated to lncRNAs) during non-small cell lung cancer (NSCLC) evolvement. We explored the profile and biological functions of the lncRNA LINC00638 in NSCLC.Methods: Reverse transcription-quantitative PCR examined LINC00638 level in NSCLC and corresponding non-tumor tissues, human normal lung epithelial cells BEAS-2B, and NSCLC cells (NCI-H460, HCC-827, A549, H1299, H1975, H460). The gain- and loss-of-function assay of LINC00638 ascertained its function in modulating the proliferation, apoptosis, and invasion of NSCLC cells (HCC-827 and H460). Bioinformatics analysis investigated the underlying mechanisms. Dual luciferase reporter gene and RNA immunoprecipitation (RIP) checked the interactions between LINC00638 and microRNA (miR)-541-3p, miR-541-3p and insulin receptor substrate 1 (IRS1).Results: LINC00638 was upregulated in NSCLC tissues by contrast to the profiles found in the corresponding non-tumor normal tissues, as well as in NSCLC cells vis-`a-vis BEAS-2B cells. LINC00638 upregulation pertained to the poorer survival rates of NSCLC patients. Overexpressing LINC00638 augmented NSCLC cells' proliferation, growth, migration, and invasion but inhibited their apoptosis, while down-regulating LINC00638 led to the opposite. miR-541-3p might be an underlying target of LINC00638, which targeted IRS1, inhibited NSCLC progression, and reversed the carcinogenic effects of LINC00638. Mechanistically, LINC00638/miR-541-3p regulated the IRS1/phosphoinositide 3-kinase (PI3K)/Akt signaling pathway. Repressing IRS1/2 using its inhibitor NT157 repressed LINC00638-mediated oncogenic effects.Conclusion: LINC00638 may function as an oncogene in NSCLC by modulating the miR-541-3p/ IRS1/PI3K/Akt axis.