Analysis of the B-RafV600E mutation in cutaneous melanoma patients with occupational sun exposure

Oncol Rep. 2014 Mar;31(3):1079-82. doi: 10.3892/or.2014.2977. Epub 2014 Jan 14.

Abstract

Sun-exposure is one of the risk factors associated with the development of a cutaneous neoplasm. In melanoma, the Ras-Raf-MEK-ERK (MAPK) signaling pathway is constitutively activated through multiple mechanisms, including B-Raf mutation. It has been hypothesized that B-Raf mutations in melanocytic lesions arise from DNA damage induced by ultraviolet (UV) radiation. However, it is still discussed if B-Raf mutations are associated with melanoma patients exposed to the sun. Therefore, in the present study, the known B-RafV600E mutation was analysed in melanoma samples from 30 indoor and 38 outdoor workers. B-RafV600E mutation was detected in 52 and 73% of outdoor workers and indoor workers, respectively. Of note, this mutation was identified in 12 of 14 (85%) melanoma of the trunk diagnosed in indoor workers and in 9 of 19 (47%) samples from outdoor workers (p=0.03). By analyzing melanomas of other body sites, no statistical difference in the frequency of B-RafV600E mutation was identified between the groups of workers. It appears that the mutation detected among indoor workers may be associated with a recreational or intermittent exposure to the sun, as usually the trunk is a sun-protected body site. Overall, these data indicate that the B-RafV600E mutation detected in melanoma is not associated with a chronic exposure to the sun. Mutations detected in other genes may also contribute to melanoma development in the subset of patients exposed to UV radiation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA Mutational Analysis
  • Female
  • Genetic Association Studies
  • Humans
  • Male
  • Middle Aged
  • Mutation, Missense
  • Neoplasms, Radiation-Induced / genetics*
  • Occupational Exposure*
  • Proto-Oncogene Proteins B-raf / genetics*
  • Skin Neoplasms / genetics*
  • Sunlight / adverse effects*

Substances

  • BRAF protein, human
  • Proto-Oncogene Proteins B-raf