PTEN and melanoma: Melanomas arising in the nf1/pten/p53-mutant background were highly invasive into underlying musculature (Fig. 1b–d), and developed much earlier than melanomas in either the Tg(mitf:BRAFV600E);p53M214K/M214K or Tg(mitf:NRASQ61K);p53M214K/M214K zebrafish [18–21].