HDAC1 and neoplasm: Importantly, we found that HRD tumors were highly enriched in immunogenic epithelial cells, infiltrated myCAFs, M1 macrophages, tumor reactive CD8+ T cells, and CD4+ Tregs, while HRP tumors were highly enriched in epithelial cells expressing HDAC1, indolent CAFs, M2 macrophages, and bystander CD4+/CD8+ T cells.