Gene array (Figure 4B) followed by real-time PCR analysis of individual genes (Figure 4C) clearly showed that p40 mAb treatment markedly increased the expression of apoptosis-related genes such as cytochrome C, caspase 3, caspase 8, caspase 9, p53, BAD, BID, BAX, and BAK in tumor tissues of PDX mice. The gene discussed is BAK1; the disease is neoplasm.