Abstract
Cutaneous malignant melanoma is unique in that a lesion, as small as 3 mm in diameter, may cause widespread and disseminated disease that is uniformly fatal owing to the extreme resistance to radio- and chemo-therapy. In this article, we review the evidence that the highly malignant character of cutaneous melanoma is due to the existence of cancer stem cells (CSC) that are responsible for tumorigenic growth and clinical relapse following therapy. Although some markers, such as MS4A1, ABCG2 and ABCB5, are repeatedly found, the various and largely nonoverlapping phenotypes of CSC suggest that either different subpopulations of CSC exist, or that melanoma CSC express a phenotype that continuously changes. For this reason, emphasis is given to identification techniques that are independent of the surface phenotype of melanoma CSC. Finally, in view of their efficient efflux of toxic substances, melanoma CSC play a crucial role in the chemoresistance of melanoma, and targeting the CSC is considered to increase the impact of chemotherapy enormously.
Acknowledgements
Many thanks to Lies Gremeaux and Anke Van den Broeck for their sustaining comments throughout the course of this review.
Financial & competing interests disclosure
The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.
No writing assistance was utilized in the production of this manuscript.
