While the role of β3 in cancer cell biology is uncertain, it is of interest to notice that two missense mutations have been identified in the SCN3B gene in high grade metastatic colorectal cancer biopsies (Sjoblom et al., 2006), and that non-mutated SCN3B gene was proposed to induce apoptosis through a p53-dependent signaling pathway in cancer cells after DNA damages (Adachi et al., 2004). The gene discussed is SCN3B; the disease is metastatic colorectal cancer.