CYP19A1 and breast cancer: More specifically, the aromatase inhibitor, a drug commonly prescribed for postmenopausal ER+ BC, has been shown to induce an increase in body fat and a reduction in insulin sensitivity [140,141,142], as well as long-term cardiotoxicity [143,144,145], osteoporosis [146,147,148], and arthralgia [149,150,151].