These findings are quite intriguing as transcriptional activation of either ABCB5, PAX3 or both might not be essential for CTC release from the tumour or CTC survival, but may feature a type(s) of CTC with tumour-initiating capabilities, which aligns with previous observations.9,10,15 PAX3 is a master regulator of melanocytic differentiation and maintenance of stem cell phenotype and migration of melanoblasts29,30 and regulates melanocytic function,31 through transcriptional regulation of MITF32 and other target genes. Here, PAX3 is linked to neoplasm.