ESR1 and breast cancer: CD44 and CD24 are characteristic of the cancer stem cell phenotype, and these molecules are closely associated with poor prognosis and chemotherapy resistance in cancer.24, 25, 26, 27 Recently, natural substances from plants have been documented as effective intervention agents in the down‐regulation of CD44/CD24 expression in experimental breast carcinoma.28 However, whether IBC can directly regulate CD44/CD24 expression to decrease paclitaxel resistance in ER+ breast cancer cells remains unclear.