Abstract 6657: ACLY-mediated acetyl-CoA levels drive bladder cancer progression

Background: As cancers progress, elucidating the underlying mechanisms of metabolic reprogramming caused by genetic alteration in cancer cells may provide a key clue for exploring druggable targets. Targeting unique metabolic reprogramming which contributes to aggressive progression in bladder cancer (BC) remains a major challenge. This study aimed to identify metabolic pathways and druggable targets that influence BC progression and remodel the tumor microenvironment. Methods: Liquid chromatography mass spectrometry-based untargeted metabolomic profiling was performed on low grade (LG) and high grade (HG) BC tissue samples of patients (N=8). The prognostic value of related metabolic genes was assessed using transcriptomic datasets (TCGA and UROMOL). To investigate the biological mechanisms underlying ACLY-acetyl-CoA-regulated BC progression, we utilized proliferation, transwell invasion, wound healing, colony formation assays, western blotting, immunoprecipitation, and immunohistochemistry, employing T24, J82, UMUC3, and MB49 cell lines and tumor tissues. BC mice models were produced by injection of MB49 cells into the bladder wall and subcutaneous tissues of C57/BL6 and BALB/C nude mice and administrated by daily oral gavage or peritoneal injection of BMS-303141. Tumor growth was monitored longitudinally using caliper measurement and bioluminescence imaging. Altered tumor microenvironment was assess by histological analysis. Results: Acetyl-CoA was one of the most significantly enhanced metabolites in HG tumor tissues compared to LG tumor tissues. In the acetyl-CoA pathway, ACLY which converts citrate to acetyl-CoA, was found to play a critical role in maintaining tumoral acetyl-CoA levels, firmly linking it to poor prognosis in BC patients. Perturbing ACLY activity through genetic knockdown (siRNA or shRNA) and pharmacological inhibition (BMC-303141) significantly reduced intracellular acetyl-CoA levels, impaired cell proliferation, migration, invasion, and colony formation, suppressed EMT marker expressions (N-cadherin, vimentin), and affected PD-L1 protein levels by acetylation. ACLY and PD-L1 protein expression were positively correlated in BC tissue microarray-based analysis. In line with this, BMS-303141 suppressed tumor growth in both immunocompetent and immunodeficient mice, with more pronounced effects observed in immunocompetent mice, suggesting an additional anti-tumor effect through ACLY-acetyl-CoA-mediated immune modulation. Conclusion: Our findings indicate that acetyl-CoA is a critical metabolite in BC progression, particularly through ACLY, the primary enzyme responsible for producing intracellular acetyl-CoA in BC cells, linked to increased BC aggressiveness. Targeting ACLY holds therapeutic potential for aggressive BC. Citation Format: Hoe Suk Kim, Jiyun Lee, Seung-il Jo, Dongmin Suh, Hyesun Lee, Sangbin Oh, Chang Wook Jeong, Ja Hyeon Ku, Cheol Kwak, Sunghyouk Park, Jang Hee Han. ACLY-mediated acetyl-CoA levels drive bladder cancer progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 6657.