A new study found that estradiol the existing drug estradiol can obstruct tumour growth in a subtype of triple-negative breast cancer. According to the Medical News Today report in the phase II clinical trial the researchers may soon test the repurposed drug. Triple-negative breast cancer is an aggressive form of breast cancer wherein tumours lack expression of three proteins. This condition is able to grow and spread more quickly than other forms of breast cancer. The three are progesterone receptor human epidermal growth factor receptor 2 (HER2) and estrogen receptor. Also specialists cannot treat them with hormone therapy because its