What do redox metabolism, printers/lithographers, and hip replacements have to do with the prevention of melanoma?
F. Meyskens, Jr. UC Irvine, Orange, CA 8583 Our studies of the properties of reactive oxygen species(ROS) in melanomagenesis led us to explore the role of heavy metals in this process. A systematic experimental exploration of the effect of ROS on melanin and melanosomes in melanocytes and melanoma cells using biophysical techniques including electroparamagnetic resonance to measure free radicals and electron microscopy suggests that the conversion of melanin from an anti-oxidant and reducing agent to a pro-oxidant and photoreactive compound is an early pathogenic event that is accompanied by melanosomal disruption that serves as an ongoing organelle source of free radical generation. The involvement of selected heavy metals enhances this process and in conjunction with ultraviolet light can lead to phenotypic changes in normal human melanocytes that resemble dysplatic nevi melanocytes in culture. A re-examination of the non-genetic risk factors for melanoma has identified a large(and n
