Tie-mei Shi

Down-regulation of lncRNA BLACAT1 inhibits ovarian cancer progression by suppressing the Wnt/β-catenin signaling pathway via regulating miR-519d-3p

Ovarian cancer has the highest mortality in gynecologic malignancies. LncRNA BLACAT1 serves crucial functions in various cancers, but its role in ovarian cancer has not been investigated. In this article, our team explored the role and the potential regulatory mechanism of BLACAT1 in ovarian cancer. Quantitative RT-PCR showed that BLACAT1 was aberrantly up-regulated in ovarian cancer tissues compared with normal tissues. In vitro, BLACAT1 knockdown induced cell cycle arrest and inhibited the proliferation, migration and invasion of ovarian cancer cells using flow cytometry, MTT and EdU assays, wound healing assay and transwell assay, respectively. Luciferase assay verified the binding relationship between microRNA-519d-3p and lncRNA BLACAT1, and BLACAT1 negatively regulated the expression of miR-519d-3p. We also found that miR-519d-3p overexpression could inhibit ovarian cancer cells proliferation, migration and invasion. Further, Western blot demonstrated that the expression of RPS15A and nuclear β-catenin expression was markedly reduced by BLACAT1 knockdown, and cytoplasmic β-catenin level was not obviously affected. In vivo, BLACAT1 knockdown inhibited the tumor growth, and immunohistochemistry showed that ki67 expression was decreased by BLACAT1 suppression. Inhibition of BLACAT1 was sufficient to down-regulate the expression of RPS15A and nuclear β-catenin but did not cause an obvious change in cytoplasmic β-catenin expression. Taken together, BLACAT1 knockdown inhibited the progression of ovarian cancer by suppressing the Wnt/β-catenin signaling pathway via regulating miR-519d-3p. Our work provided a proper understanding of the critical roles of BLACAT1 in ovarian cancer.

Long non-coding RNA LINC00460 promotes proliferation and inhibits apoptosis of cervical cancer cells by targeting microRNA-503-5p

Long non-coding RNAs are associated with the pathogenesis of cancers. Moreover, LINC00460 is involved in the development of multiple cancers. However, the function of LINC00460 in cervical cancer (CC) remains inconclusive. Herein, CC tissues and tumor-adjacent tissues were collected from patients. The effect of LINC00460 silencing in cell proliferation and apoptosis in CC was explored in vitro and in vivo. Additionally, the interaction between LINC00460 and miR-503-5p was analyzed using dual luciferase reporter assay. The expression of genes and proteins was assayed using quantitative real-time PCR, western blotting and immunohistochemistry, cell viability using MTT assay, cell cycle distribution using flow cytometry, cell apoptosis using Annexin V staining, Hoechst staining and TUNEL assay. LINC00460 levels in CC tissues were higher than tumor-adjacent tissues. LINC00460 silencing suppressed proliferation and promoted apoptosis of CC cells as evidenced by decreased cell viability, inhibited proliferation-related protein and cell cycle protein expressions and G1/S transition, increased apoptotic cells and Hoechst-positive cells, and enhanced apoptosis-related protein expressions. LINC00460 could bind to miR-503-5p and LINC00460 silencing enhanced miR-503-5p expression and inhibited its target gene expressions in CC cells. MiR-503-5p inhibition reversed LINC00460 silencing-caused inhibition of cell proliferation and miR-503-5p target gene expressions, and promotion of cell apoptosis. LINC00460 silencing also attenuated tumor growth, promoted miR-503-5p levels and cell apoptosis, and inhibited cell proliferation and miR-503-5p target gene expressions in tumor tissues. Hence, LINC00460 functioned as an oncogene in CC that affected cell proliferation and apoptosis via sponging miR-503-5p. This study provides a novel therapeutic target for CC.