Abstract LB039: Ovarian cancer cell-derived exosomal UCA1 reprograms glucose metabolism in stromal fibroblasts

Abstract

Abstract Tumor progression is stringently regulated by the co-ordinated signaling between the tumor cells and the tumor microenvironment (TME) through diverse autocrine, paracrine and exocrine signaling mechanisms. Recent studies have shown that the exosomes that play a crucial role in the transfer of oncogenic macromolecules and oncometabolites to different cellular components of the TME can be targeted for therapy. Therefore, with the focus on identifying the exosomal long non-coding RNA (lncRNA) that can be therapeutically targeted, we investigated the profile of ovarian cancer cell derived lncRNAs and their functional role in ovarian cancer pathophysiology. Analysis of exosomes derived from a panel of high grade serous ovarian cancer cell lines indicated that UCA1 (Urothelial Cancer Associated 1) is the most abundantly packaged lncRNA in the exosomes. Similarly, exosomes from patient-derived ovarian cancer cells exhibited higher levels of UCA1. Ascites from ovarian cancer patients also indicated high levels of UCA1 in the ascites-derived exosomes. Results using PKH67-labelled ovarian cancer cell-derived exosomes and MRC5 fibroblast cell line indicated the exosomal transfer of UCA1 to the fibroblasts. Since paracrine signaling has been shown to induce metabolic reprogramming of peritumoral fibroblasts, we interrogated whether exosomal transfer of UCA1 could reprogram the glucose metabolism in the fibroblasts. Results from the Agilent Seahorse glycolytic stress assay indicate that the exosomal UCA1 promotes reprogramming of glucose metabolism in fibroblast cells while depleting of UCA1 in the exosomes failed to induce such metabolic reprogramming. Results from the analysis of the key glycolytic enzymes in the stromal fibroblasts, post-exosomal UCA1 uptake also corroborate this conclusion. Thus our results provide primary evidence that the exosomal-UCA1 induces pro-tumorigenic metabolic reprogramming in peri-tumoral fibroblasts. Together with the known oncogenic role of UCA1 in many different cancer cells, our findings indicate that targeting UCA1 could form a productive precision cancer strategy in ovarian cancer, targeting both the tumor cells and tumor stromal cells. This research was supported by the Department of Defense Ovarian Cancer Research Program Award W81XWH-18-1-0066, W81XWH-22-1-0415, the National Institute of General Medical Sciences grant P20 GM103639 and The National Cancer Institute of the National Institutes of Health grant P30 CA225520. Citation Format: Revathy Nadhan, Ji Hee Ha, Muralidharan Jayaraman, Srishti Kashyap, Danny N. Dhanasekaran. Ovarian cancer cell-derived exosomal UCA1 reprograms glucose metabolism in stromal fibroblasts [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB039.