BACKGROUNDThis study investigates the combined effects of the epigenetic anticancer drug 5-azacytidine (5-Aza) and N6-methyladenosine (m6A) on breast cancer stem cells (CSCs) and normal breast epithelial cells. CSCs are characterized by their ability to self-renew, their resistance to conventional therapies, and their role in metastasis, presenting a significant challenge in breast cancer treatment.METHODS AND RESULTSThe study utilized flow cytometry to isolate CD44 + /CD24low CSCs from MCF-7 breast cancer cells and evaluated these cells through spheroid formation assays. The results demonstrated that both 5-Aza and m6A, both individually and in combination, exert cytotoxic effects on CSCs, induce apoptosis, and reduce their migratory capacity. Importantly, these treatments did not produce similar effects on normal breast epithelial cells (MCF-10A), indicating selective action on CSCs. Gene expression analysis revealed that treatment with 5-Aza, m6A, and their combination altered the expression of key stem cell-related genes, including OCT4, NANOG, SOX2, and c-MYC, which are associated with CSC self-renewal and malignancy.CONCLUSIONSThese findings suggest that epigenetic modulation through 5-Aza and m6A could effectively target CSCs, disrupting their ability to drive tumor progression and metastasis, particularly in aggressive breast cancer subtypes. This study highlights the potential of 5-Aza and m6A as a combinatorial therapeutic approach, offering a promising avenue for improving treatment outcomes in breast cancer patients, especially those with therapy-resistant disease. Further clinical investigation is needed to validate these findings and explore their therapeutic implications.