Friday, April 4, 2025
4/4/2025
Rac-enhanced Chimeric Antigen Receptor-Macrophage (Race-CAR-M) Immunotherapy for Triple Negative Breast Cancer - Project Summary Triple-Negative Breast Cancer (TNBC) is an aggressive subtype lacking estrogen, progesterone, and HER2 receptors, limiting targeted therapy options. Conventional systemic therapies, such as chemotherapy, are non- specific, leading to significant toxicity. Despite the success of Chimeric Antigen Receptor T-cell (CAR-T) therapy in hematologic cancers, its use in solid tumors like TNBC is hindered by challenges such as an antigen heterogeneity, immunosuppressive tumor microenvironment (TME), and limited T-cell infiltration. Macrophages can engulf pathogens, dying cells, and cancer cells and naturally infiltrate TME. An innovative approach involves engineering macrophages to express Chimeric Antigen Receptor (CAR) that specifically target antigens on cancer cells, thereby creating CAR-Macrophages (CAR-Ms). This project aims to develop and evaluate a novel CAR-M therapy targeting Chondroitin Sulfate Proteoglycan 4 (CSPG4), overexpressed in TNBC. Our earlier findings demonstrated that co-expression of an active form of Rac2 (Rac2E62K) with a CAR enables macrophages to specifically recognize and engulf living target cancer cells. Hence, Rac2 activation in anti-CSPG4 CAR-Ms is proposed to enhance tumor-infiltrating and phagocytic capabilities, leading to improved tumor targeting and eradication. This study aims to evaluate the specificity, efficacy, and impact on angiogenesis of anti-CSPG4, Rac-enhanced CAR-Ms (Race-CAR-Ms) using the chicken chorioallantoic membrane (CAM) model. The CAM model will facilitate detailed in vivo analyses, including tumor infiltration, tumor regression, and metastatic dissemination. Additionally, the anti-angiogenic potential of anti-CSPG4 Race-CAR-Ms will be investigated by measuring levels of proangiogenic factors and visualizing blood vessel formation through advanced imaging techniques. Optimizing the engulfment potential of anti-CSPG4 Race- CAR-Ms in the TNBC microenvironment requires a thorough understanding of their energy requirements and metabolic flexibility. Hence, the project focuses on metabolic profiling of anti-CSPG4 Race-CAR-Ms. Liquid chromatography-mass spectrometry (LC-MS) and flow cytometry-based metabolic assays will be used to identify key metabolic pathways and assess reactive oxygen species (ROS) production. The proposed research integrates advanced imaging, molecular biology techniques, and metabolic assays to elucidate the therapeutic potential anti-CSPG4 Race-CAR-Ms in TNBC. The outcomes are expected to provide significant insights into the efficacy and specificity of anti-CSPG4 Race-CAR-M therapy for TNBC and has the potential to contribute to the development of targeted immunotherapy for aggressive TNBC.
HHS’ Tracking Accountability in Government Grants System (TAGGS) website provides access to detailed descriptions of grants, loans, aggregated direct payments and other types of financial assistance awarded by the HHS Operating Divisions (OPDIVs) and the Office of the Secretary Staff Divisions (STAFFDIVs).