Researchers at the U-M Comprehensive Cancer Center, along with scientists at Washington University in St. Louis, have found that a particular gene reverses the cancer-like growth characteristics of human melanoma cells. Melanoma is an often fatal form of skin cancer whose incidence is increasing faster than any other form of cancer.
Findings of the study have been published in the April issue of the Journal of the National Academy of Sciences.
Investigators at the U-M include Paul Meltzer, assistant professor of pediatrics, and Jeffrey M. Trent, deputy director of the center and the Emanuel N. Maisel Professor of Oncology.
These results extend our knowledge of one of the bodys natural defense systems known to prevent cell damage caused by irradiation, ultraviolet light and other environmental carcinogens, Trent says. Our work further suggests that this gene may also have an effect on cell growth.
The segment of the chromosome on which the gene called MnSOD is found is often missing in malignant skin cancers. The researchers conclude that introducing the gene into human melanoma cells has the same tumor-suppressing effects as introducing the entire chromosome.
The incidence of melanoma in the United States has almost tripled in the past four decades, growing faster than any other type of cancer in the populations. Approximately 36,000 Americans were diagnosed with melanoma in 1992, and about 20 percent of those individuals will die from it. If not diagnosed early, the death rate climbs to almost 100 percent. Projections suggest that melanoma will develop in one in 90 Americans by the year 2000.
Melanoma affects adults in all age groups, with a median age at diagnosis of 53. In young adults, melanoma has the highest annual incidence rate of any cancer in Caucasians between the ages of 25 and 29, and in Caucasian males ages 3539.
The current five-year survival rate of 80 percent is a vast improvement from the 49 percent survival rate in the early 1950s.
The precise cause of melanoma is unknown. Major risk factors include sun exposure, especially repeated blistering sunburns during childhood.
Investigators at Washington University include James Grant and Susan Church, both assistant professors of pediatrics.