A SNP-Mediated lncRNA-microRNA Interaction in Association with NSCLC Risk

Background: Many cancer-associated single nucleotide polymorphisms (SNPs) are located in the genomic regions of long non-coding RNAs (lncRNAs). Mechanisms of these SNPs in connection to cancer risk are not fully understood. Methods: SNP (rs140618127) in lncRNA LOC146880 relating to non-small cell lung cancer (NSCLC) were genotyped based on a 2707 individuals’ case-control study. The mechanism was explored using cell experience and xenograft animal model. Total RNA and miRNA were extracted from cell lines to quantify the RNA levels of genes by qPCR. siRNAs were used to transfected with targeted genes; and mimic was used to detect the luciferase activity. RNA pulldown and mass spectrometry analysis were used to find out the target genes. Cells infected with lentivirus containing LOC146880 were homogenized for immunoblotting or immunoprecipitation. The effects of this SNP on cell were evaluated by CCK8, flow cytometry, colony formation assays, and Transwell. Findings: SNP rs140618127 [A], ‘A’ allele, is a protective factor of NSCLC. Results shown that rs140618127 contained a binding site for miR-539-5p and the binding between miR-539-5p and LOC146880 resulted in declined phosphorylation of an oncogene, ENO1. Furthermore, the reduced phosphorylation of ENO1 led to decreased phosphorylation of PI3K and Akt, which is linked to the decline in tumor cell proliferation and progress. Interpretation: This study provides an evidence to the unsubstantiated hypothesis of SNP modulating miRNA-lncRNA interaction, through which SNP affects the downstream phosphorylation of the lncRNA’s target ENO1, resulting in inhibition of tumor growth and metastasis and leading to a better prognosis. Funding Statement: Natural Science Foundation of China Grant (to BQ, 81602929). Declaration of Interests: The authors declare no potential conflicts of interest. Ethics Approval Statement: This study was approved by the Institutional Review Board at China Medical University, Shenyang, China. Content of the study was written in the informed consent form, which was signed by all patients. All animal experiments were approved by the Animal Care and Use Committee of Shanghai Jiao Tong University School of Medicine (Shanghai, China).