Interestingly, high levels of stage I–III melanosomes have been linked to cisplatin resistance in highly pigmented MNT-1 melanoma cells due to drug trapping inside the melanosomes.59 In our study of metastatic melanoma specimens, disrupted melanin production was associated with poor patient survival; if validated in earlier stage disease in a larger patient cohort, these markers of stagnating melanosome maturation (high ITGAV expression in high PMEL-expressing tumors and the loss of RAB27A) might indicate a causative role for this phenotype of poor survival. This evidence concerns the gene RAB27A and metastatic melanoma.