UPF1 and melanoma: Given that the UPF1 gene, whose product represents the core component of NMD machinery, is commonly mutated in pancreatic adenosquamous carcinoma [122], melanoma-specific NMD target transcripts with retained introns may be likely upregulated in a defective UPF1-dependent manner, providing cells with critical malignancy advantages, such as therapy resistance and metastasis.