LINC01176 Hinders Thyroid Cancer Progression by Sponging miR-146b-5p to Enhance SGIP1

Abstract

Background: Long non-coding RNA (lncRNAs) plays a crucial role in tumor pathogen-esis. However, the function of most of these genes remains unclear. Aims: In the present study, we aimed to unveil LINC01176’s role in thyroid cancer. Methods: Western blotting and qRT-PCR were applied for the analysis of the expressions of LINC01176, miR-146b-5p, and SH3GL interacting endocytic adaptor 1 (SGIP1). Proliferative and migratory capabilities were assessed using the CCK-8 assay and wound-healing experiments, re-spectively. Apoptosis of the cells was studied by quantifying the apoptosis-related markers Bcl-2 and Bax by western blotting. Animal models were established using nude mice to determine the role of LINC01176 in tumorigenesis. MiR-146b-5p’s putative binding to LINC01176 and SGIP1 was validated using dual-luciferase reporter and RIP analyses. Results: LINC01176 expression was downregulated in the thyroid cancer cell lines and tissues. LINC01176 overexpression represses cancer cell proliferation and migration but induces apoptosis. Elevated LINC01176 expression hampers tumorigenesis in animal models. LINC01176 targeted miR-146b-5p and negatively regulated its expression. Enrichment of miR-146b-5p counteracted the functional effects of LINC01176 overexpression. Additionally, miR-146b-5p interacted with SGIP1 and negatively regulated its expression. Thus, miR-146b-5p attenuates the anti-cancer ef-fects of SGIP1. Conclusion: LINC01176 negatively regulates the expression miR-146b-5p and upregulates SGIP1 expression. Hence, LINC01176 blocks the malignant progression of thyroid cancer.