P2X7 activation in various cell types, including macrophages, lymphocytes (such as T lymphocytes and B lymphocytes), glial cells (microglia and astrocytes), and tumor cells (including most human tumor cells such as breast cancer, gastric cancer, colorectal cancer, and lung cancer cells), triggers the activation of associated signaling pathways like MAPK, JNK, and ATK. The gene discussed is P2RX7; the disease is breast carcinoma.