Koshy et al. discovered that a minority of human NK cells, defined as adherent NK cells, is able to nearly double the number of their KV1.3 and KCa3.1 channels after their activation by cocultured cancer cells (KV1.3: 50 to 125/cell; KCa3.1: 20 to 40/cell). This evidence concerns the gene KCNN4 and cancer.