Abstract 3745: GRAS1 long non-coding RNA binds and stabilizes NF-kB activating protein to protect lung cancer cells from DNA damage

Abstract Long non-coding RNAs (lncRNAs) control numerous biological processes, including epigenetic regulation, gene expression, proliferation and metabolism. However, the detailed biological mechanisms by which lncRNAs regulate cellular processes are still poorly understood. We identified a set of growth regulator non-coding RNAs based on data mining of CRISPR/Cas9 screens and high-throughput sequencing studies from patient normal and tumor cells. We hypothesized that growth regulator lncRNAs play a role in cancer development by recruiting effector proteins to regulate gene expression. In our screen, the Growth Regulator Antisense 1 RNA (GRAS1) was identified as a key factor controlling growth in non-small cell lung cancer cells. Loss of GRAS1 resulted in altered expression of genes involved in DNA repair, cell cycle progression, and p53 and NF-ΚB signaling pathways. Extensive DNA damage occurred within 48 hours after GRAS1 knockdown, with a significant increase in the number of γH2AX loci visualized by immunofluorescence assay. We used RNA antisense purification combined with mass spectrometry to identify the NF-ΚB activating protein (NKAP) as the top directly interacting partner of GRAS1 lncRNA. NKAP stability decreased after GRAS1 knockdown, and this phenotype could be reversed with proteasome inhibition. Further, RelA levels were decreased in GRAS1 knockdown cells. We found that GRAS1 lncRNA binds and stabilizes NKAP to enable survival and protect against DNA damage in lung cancer cells. Citation Format: Tong Su, Bobby Kong, Jonathan Zhu, Colleen A. McHugh. GRAS1 long non-coding RNA binds and stabilizes NF-kB activating protein to protect lung cancer cells from DNA damage. [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 3745.