Second, as expected, we found marked upregulation of apoptosis-related genes such as cytochrome C, caspase 3, caspase 8, caspase 9, p53, BAD, BID, BAX, and BAK in tumor tissues of p40 mAb-treated PDX mice as compared to that of either untreated or control IgG-treated PDX mice. Here, BAK1 is linked to neoplasm.