This invention relates to antibodies to anti-cancer antibodies and uses thereof, including combination therapies and compositions. Combinations targeting the extrinsic, intrinsic, or common pro-apoptotic pathways are provided. Exemplary anti-cancer antibodies are differentially expressed in cancers, such as antibodies targeting the bind the antigens NPC-1, 16C3, or 31.1. Exemplary anti-cancer antibodies target lung cancer, ovarian cancer, cervical cancer, uterine cancer, pancreas cancer, breast cancer, and colon cancer.