PGR and triple-negative breast carcinoma: In contrast, triple-negative breast cancers, which are negative for ERα, for the progesterone receptor and for the human epidermal growth factor receptor 2, are highly aggressive and treatment options are, so far, restricted to cytotoxic agents.30 In this study, focusing on triple negative breast cancers, we unveiled the precise molecular events underlying ERα-36-mediated signaling pathway.