Abstract 1635: Inhibition of FANCA Suppresses Breast Cancer Development by Regulating Cell Cycle Progression

Abstract

Abstract FANCA is one of the 22 known Fanconi anemia (FA) pathway genes that are involved in interstrand crosslink (ICL) repair. We have also shown that and FANCA plays a role in double strand break repair by promoting strand annealing and exchange. In this report, we describe that FANCA expression in breast cancer is significantly elevated within TCGA databases and in patient tumors-derived sections on both transcription and translation levels and this elevation is associated with poor outcomes of the breast cancer patients. Importantly, we have found that overexpressing FANCA in breast cancer cell line MDA-MB-231 promotes tumor growth both in vitro and in vivo. We have also demonstrated that FANCA inactivation by knocking out or knocking down inhibits growth of MDA-MB-231 in vitro and in vivo by causing cell cycle arrest at G1 phase resulting from hypophosphorylation of Rb protein. Our RNA-seq data has indicated that E2F targets are also downregulated in FANCA knockout (KO) cells compared to the wildtype (WT) MDA-MB-231 cells, which is consistent with the G1/S cell cycle arrest and Rb hypophosphorylation. Intriguingly, heterozygous FANCA KO in a breast cancer mouse model MMTV-PyMT model has shown reduction of breast tumor formation and volume. Our goal is to elucidate the role of FANCA in breast cancer development and to evaluate the potential of FANCA as a target for breast cancer treatment. Citation Format: Liang Luo, Wenjun Liu, Fenghua Yuan, Fang Li, Anna Palovcak, Daniel Calkins, Karoline Briegel Briegel, Yan Li, Christian Mason, Zhao-Jun Liu, Sylvia Daunert, Yanbin Zhang. Inhibition of FANCA Suppresses Breast Cancer Development by Regulating Cell Cycle Progression [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(6_Suppl):Abstract nr 1635.