Estrogen (steroid) and estrogen receptors have been implicated in breast cancer, ovarian cancer, colon cancer, prostate cancer, and endometrial cancer amongst others. Accordingly, several drugs have been identified for the treatment of these diseases hovering around this concept (e.g. steroidal and non-steroidal aromatase inhibitors, estrogen receptor antagonists, and anti-androgens). Provide the names and structures of one (or more) drug(s) that have been approved in each of these categories.