While melanoma makes up only 4 percent of all skin cancers, it causes about 79 percent of skin cancer deaths, and it is the only type that can spread through the bloodstream to internal organs. Roughly 47,700 American develop melanoma annually, and it can strike anyone. Disturbingly, the death rate for melanoma has increased by about 44 percent since 1973, most rapidly among white men over the age of 50. Risk factors for this disease include moles, fair skin, family history, age and too much exposure to ultraviolet radiation and sunburn. If you catch it early enough, it's treatable.
Normal cells grow and divide, but have a limited life span.
A natural system of programmed cell death called apoptosis keeps the body's system of young, healthy cells and older or worn-out cells in balance. But cancerous cells don't have a programmed cell death, and instead wildly multiply, form tumors and can even spread throughout the body. In many cancers, scientists have found that a defect in the p53 gene allows cells to sidestep the natural dying process, but this is not the case with melanoma. Now, Soengas and her colleagues have found an abnormality in another gene further along the apoptosis pathway. The gene, called Apaf-1, is missing one copy, and the second copy is switched off.