c-KIT signaling as the driving oncogenic event in sub-groups of melanomas

Histol Histopathol. 2009 May;24(5):643-50. doi: 10.14670/HH-24.643.

Abstract

As we enter the era of targeted therapy for melanoma, attempts are being made to sub-group tumors on the basis of their driving oncogenic mutations, with the hope of developing truly personalized therapeutic regimens. c-KIT is a receptor tyrosine kinase whose aberrant activation is implicated in the progression of gastrointestinal stromal tumors and some acute myeloid leukemias. The role of c-KIT signaling in melanoma has been controversial; although c-KIT activity is critical to melanocyte development, its expression tends to be lost in most melanomas. Some reports have even shown that the re-expression of c-KIT induces apoptosis in melanoma cell lines. The recent publication of work showing the presence of activating c-KIT mutations in acral and mucosal melanomas, as well as melanomas arising on skin with chronic sun damage, has renewed interest in c-KIT signaling in melanoma. Recent work from our own laboratory has further identified melanomas with constitutive c-KIT signaling activity resulting from c-KIT receptor overexpression. Although the initial clinical trials of the c-KIT inhibitor imatinib mesylate in melanoma were negative, some dramatic responses have been seen in patients with very high c-KIT expression and/or documented activating mutations, fostering the belief that focused studies in patients selected on the basis of c-KIT mutational status will yield more encouraging results. The current review discusses the role of c-KIT signaling in melanoma progression and how this new information can be applied to the targeted therapy of melanoma.

Publication types

  • Review

MeSH terms

  • Animals
  • Benzamides
  • Humans
  • Imatinib Mesylate
  • Melanocytes / cytology
  • Melanocytes / enzymology
  • Melanoma / classification
  • Melanoma / enzymology*
  • Melanoma / etiology*
  • Melanoma / genetics
  • Melanoma, Experimental / classification
  • Melanoma, Experimental / enzymology
  • Melanoma, Experimental / etiology
  • Melanoma, Experimental / genetics
  • Mice
  • Models, Biological
  • Mutation
  • Piperazines / therapeutic use
  • Protein Kinase Inhibitors / therapeutic use
  • Proto-Oncogene Proteins c-kit / chemistry
  • Proto-Oncogene Proteins c-kit / genetics
  • Proto-Oncogene Proteins c-kit / metabolism*
  • Pyrimidines / therapeutic use
  • Signal Transduction
  • Stem Cell Factor / genetics
  • Stem Cell Factor / metabolism
  • Uveal Neoplasms / enzymology
  • Uveal Neoplasms / etiology
  • Uveal Neoplasms / genetics

Substances

  • Benzamides
  • Piperazines
  • Protein Kinase Inhibitors
  • Pyrimidines
  • Stem Cell Factor
  • Imatinib Mesylate
  • Proto-Oncogene Proteins c-kit