Abstract 3762: A novel lncRNA, GTF2A1-AS1, is required for cell cycle progression and cell proliferation

Abstract

Long noncoding RNAs (lncRNAs) are major regulators of many cellular processes including cell cycle progression, cell proliferation and tumorigenesis. In this study, we identify a novel lncRNA, GTF2A1-AS1, and reveal its effects on cell cycle progression and cancer growth. Inhibition of GTF2A1-AS1 expression alters cell cycle distribution, leading to a decrease in the number of G1 cells and a concomitant increase in all other stages of the cell cycle, and in particular S phase, suggesting its involvement in the regulation of G1/S transition. Accordingly, knock down of GTF2A1-AS1 enhances G1 phase exit upon release from a late G1 block. In agreement with its suggested role in G1/S transition, prolonged silencing of GTF2A1-AS1 enhances proliferation of human cancer cells. GTF2A1-AS1 RNA is mostly nuclear and its gene is localized upstream to the protein-coding gene GTF2A1. GTF2A1-AS1 functions in trans to repress the expression of EIF5A2 and HOXA13. Knockdown of either EIF5A2 or HOXA13 rescues the effects of GTF2A1-AS1 silencing on cell proliferation, indicating that it functions mainly by modulating the levels of these two proteins. In agreement with the effect of GTF2A1-AS1 silencing on cell cycle progression and cell proliferation, low levels of GTF2A1-AS1 are associated with reduced survival in brain cancer patients. In conclusions, our data identify GTF2A1-AS1 as a novel lncRNA that regulates cell-cycle progression and cell proliferation and has a potential role in human cancer. Citation Format: Yael Goldstein, Tali Nizri-Megnaji, Doron Ginsberg. A novel lncRNA, GTF2A1-AS1, is required for cell cycle progression and cell proliferation. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3762.