Abstract 5910: Developing a novel humanized anti-FABP4 antibody for breast cancer treatment

Abstract Circulating levels of adipocyte fatty acid binding protein (A-FABP, also known as FABP4) are linked with metabolic dysregulation. Our previous study demonstrated that high serum levels of FABP4 increased the risk of breast cancer, indicating that circulating FABP4 could be a potential therapeutic target for this disease. In this study, we generated mouse monoclonal antibodies (mAb) against FABP4 by immunizing C57BL/6 mice with recombinant human FABP4. After screening over 1300 hybridoma clones, we identified an FABP4 neutralizing mAb, named 12G2, which inhibited breast cancer growth in various mouse models. To facilitate clinical application, we engineered chimeric and humanized variants of the 12G2 mAb. Notably, the humanized variant, 12G2-variant 9 (12G2-vt9), effectively inhibited mammary tumor growth and progression by reducing the activity of FABP4/ALDH1 in different breast cancer mouse models. Our findings suggest that 12G2-Vt9 is a promising neutralizing mAb targeting FABP4-mediated cancer stemness through ALDH1 signaling, offering potential as a targeted therapeutic antibody for the clinical treatment of breast cancer. Citation Format: Jiaqing Hao, Matthew Yorek, Jian yu, Anthony Avellino, Bing Li. Developing a novel humanized anti-FABP4 antibody for breast cancer treatment abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 5910.