Study of Enzalutamide With and Without Sorafenib in Advanced Hepatocellular Carcinoma Patients

The purpose of this study is to test the safety of enzalutamide with or without sorafenib at different doses. Enzalutamide is approved by the Food and Drug Administration (FDA) for the treatment of advanced prostate cancer. Enzalutamide blocks a protein called the androgen receptor. Experiments on liver cancer cells and animal models show that blocking the androgen receptor causes liver cancer to stop growing. Enzalutamide has not been approved to treat liver cancer. The investigators want to see if enzalutamide is safe for patients with liver cancer who have had their tumors grow on sorafenib. The investigators also want to see how safe and effective sorafenib and enzalutamide are for liver cancer patients that have never been treated with sorafenib. This is the first time enzalutamide and sorafenib are being used together. This treatment may not help treat the participant's cancer.