Examples are ATP-sensitive potassium (KATP) channels in breast cancer cells [27, 40], KV4.1 channels in human gastric cancer cell lines [19] and tumorigenic human mammary epithelial cells [12], KV1.3 channels in lung adenocarcinoma cells [13], and KV11.1 channels in neuroblastoma cells [41]. The gene discussed is KCNA3; the disease is gastric cancer.