CTC1 and melanoma: Our analysis showed that the combined gene alteration frequency of CTC1, STN1 and TEN1 in human melanoma is ~ 9%, within the range of alteration frequency of some of the well-known melanoma-associated genes like PTEN, p53, and TERT, although NRAS, BRAF are the top altered genes in melanoma [30,31] (Fig 1A).