LIMD1-AS1 suppressed non-small cell lung cancer progression through stabilizing LIMD1 mRNA via hnRNP U

Abstract

Background: Non-small cell lung cancer (NSCLC) occupies the majority of lung cancer cases and is notorious for the awful prognosis. LIM domains-containing 1 (LIMD1) is suggested as a tumor suppressor in lung cancer, but its mechanism in NSCLC remains elusive. Present study aimed to uncover the mechanism of LIMD1 in NSCLC. Methods: qRT-PCR was performed to analyze the level of LIMD1. The functions of LIMD1 in NSCLC cells were evaluated by CCK-8, EdU, and caspase-3 activity assays. RIP and pull-down assays were applied to determine the interaction of LIMD1 with heterogeneous nuclear ribonucleoprotein U (hnRNP U) and LIMD1-AS1. Results: LIMD1 was downregulated in NSCLC samples and cells. Functionally, LIMD1 hindered proliferation and drove apoptosis in NSCLC cells. Moreover, long noncoding RNA (lncRNA) LIMD1 antisense RNA 1 (LIMD1-AS1) was downregulated in NSCLC samples and cell lines. LIMD1-AS1 knockdown abrogated NSCLC cell growth in vitro and in vivo. Mechanistically, LIMD1-AS1 stabilized LIMD1 mRNA through interacting with hnRNP U. Rescue experiments suggested that LIMD1-AS1 repressed NSCLC progression through LIMD1. Conclusions: LIMD1-AS1 suppressed NSCLC progression through stabilizing LIMD1 mRNA via hnRNP U, providing new thoughts for the improvement of molecular-targeted therapy for NSCLC.