IncRNA EPB41L4A-AS1 Mitigates the Proliferation of Non-Small-Cell Lung Cancer Cells through the miR-105-5p/GIMAP6 Axis

Non-small-cell lung cancer (NSCLC) is the major subtype of lung cancer, with a series of long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and proteins involved in its pathogenesis. This study sought to investigate the functionality of lncRNA EPB41L4A antisense RNA 1 (lncRNA EPB41L4A-AS1) in the proliferation of NSCLC cells and provide a novel theoretical reference for NSCLC treatment. Levels of lncRNA EPB41L4A-AS1, miR-105-5p, and GTPase, IMAP family member 6 (GIMAP6) in tissues and cells were measured by RT-qPCR and the correlation between lncRNA EPB41L4A-AS1 and clinicopathological characteristics was analyzed. Cell proliferation was evaluated by cell counting kit-8 and colony formation assays. The subcellular localization of lncRNA EPB41L4A-AS1 was analyzed by the subcellular fractionation assay and the binding of miR-105-5p to lncRNA EPB41L4A-AS1 or GIMAP6 was analyzed by dual-luciferase and RNA pull-down assays. Functional rescue experiments were performed to analyze the role of miR-105-5p/GIMAP6 in NSCLC cell proliferation. lncRNA EPB41L4A-AS1 and GIMAP6 were downregulated while miR-105-5p was upregulated in NSCLC tissues and cells. lncRNA EPB41L4A-AS1 was correlated with tumor size and clinical staging and its overexpression reduced NSCLC cell proliferation. lncRNA EPB41L4A-AS1 was negatively correlated with miR-105-5p and positively correlated with GIMAP6 in NSCLC tissues, and lncRNA EPB41L4A-AS1 sponged miR-105-5p to promote GIMAP6 transcription in NSCLC cells. Overexpression of miR-105-5p or knockdown of GIMAP6 reversed the inhibition of lncRNA EPB41L4A-AS1 overexpression on NSCLC cell proliferation. lncRNA EPB41L4A-AS1 was downregulated in NSCLC and mitigated NSCLC cell proliferation through the miR-105-5p/GI-MAP6 axis.