CD24 and breast carcinoma: In the triple-negative breast cancers, metformin has been shown to suppress the metastasis-associated protein and breast CSC marker CD24 [139], suggesting a therapeutic role for metformin-based regimens in the clinical management of highly metastatic subgroups of triple-negative/basal-like breast carcinomas naturally enriched with CD24-positive tumor-initiating cells [140-142].