In addition, the more bioavailable character of MART-10 as compared to 1α,25(OH)2D3 in MCF-7 cells and its noncalcemic nature in an animal model suggest that MART-10 has potential as a superior chemotherapeutic agent to replace or to be in combination with traditional antihormone therapy for the treatment of breast cancer, such as the ER+ breast cancer patients, to decrease the tumor recurrence and eliminate the side effect on bone caused by the antihormone treatments. Here, ESR1 is linked to breast cancer.