Here, we harnessed female C57BL/6J mice lacking key regulators of MPT-driven necrosis and necroptosis to investigate whether whole-body defects in these pathways would influence mammary carcinogenesis as driven by subcutaneous slow-release medroxyprogesterone acetate (MPA, M) pellets plus orally administered 7,12-dimethylbenz[a]anthracene (DMBA, D), an in vivo model that recapitulates multiple facets of the biology and immunology of human hormone receptor positive (HR+) breast cancer. This evidence concerns the gene NR4A1 and breast cancer.