PTK2 and melanoma: In addition to the use of ERKi, the current gold-standard treatment combining the use of targeted inhibitors with immunotherapies suggests there may be efficacy in further combining BRAF or MEK inhibitors with those against other known mediators of anoikis resistance described in this review to target CTCs, especially given the considerable level of crosstalk between MAPK, PI3K-Akt, EGFR, FAK and other key signalling pathways in melanoma.