Meanwhile, the cocultures of chloroquine-treated Par-4+/+ MEFs plus H-460 lung p53+/+ and H-1299, HOP92, and KP-7B lung or prostate PC-3 p53−/− cancer cells were sensitive to apoptosis, but not when cocultured with chloroquine-treated Par-4−/− MEFs, and chloroquine failed to induce Par-4 secretion in prostate cancer cells (LNCaP, C42B, DU-145, and PC-3) and lung cancer cells (H-460 and A-549). This evidence concerns the gene TP53 and prostate cancer.