A team of biologists led by a scientist at MIT has reported the rough location of a gene that may play a crucial role in the early growth of melanoma skin cancer.
The work, which could lead to new diagnostic strategies and treatments for melanoma, was published in the November 1 issue of the Proceedings of the National Academy of Sciences.
The first author of the paper is Jane W. Fountain, a postdoctoral fellow in the Center for Cancer Research (CCR) who works in the laboratory of Professor David E. Housman of biology, a co-author of the paper. Other MIT authors are Maria Karayiorgou, a postdoctoral associate at the CCR, and Nicholas C. Dracopoli, a principal research scientist at the Center for Genome Research.
Their colleagues in the work are Marc S. Ernstoff and Linda Titus-Ernstoff of Dartmouth University; John M. Kirkwood and Daniel R. Vlock of the University of Pittsburgh; Brigitte Bouchard, Setaluri Vijayasaradhi, and Alan N. Houghton of the Memorial Sloan-Kettering Cancer Center, and Jill Lahti and Vincent J. Kidd of St. Jude Children's Research Hospital in Memphis.
According to Dr. Fountain, evidence from a number of studies, including the one just published, "suggests that a rearrangement or deletion of a gene on chromosome 9 (one of the 23 pairs of human chromosomes found in every cell) may be the first or an initiating event in the development of melanoma."
"This type of gene," she continued, "is known as a tumor suppressor gene. It's normal function is to keep cell growth in check." When this gene is deleted from the chromosome or undergoes a mutation, "it presumably allows the predestined tumor cells to grow in an aberrant or uncontrolled fashion."
Dr. Fountain and colleagues have taken a step towards locating the tumor suppressor gene for melanoma by "narrowing the [search] on chromosome 9 down to a few million base pairs (there are approximately 145 million base pairs total on this chromosome)." The team is now "actively searching for candidate genes in this region."
Dr. Fountain expects that it will take from one to three years to identify the culprit gene, and from five to 10 years to potentially develop new diagnostic strategies and treatments for melanoma based on this information.
New treatments for melanoma are important because although the disease is easily cured by surgery when caught early, advanced cases are still difficult to treat. According to Dr. Fountain, a number of therapies have been tested in treating advanced melanoma, but "none to date are very effective in arresting tumor growth."
In the United States about 32,000 individuals are diagnosed with melanoma every year. Of those, Dr. Fountain said, from 8,000-16,000 will die within 10 years after diagnosis.
She notes, furthermore, that "over the past 10 to 20 years the incidence of melanoma has increased dramatically, more so than for any other form of human cancer, with the possible exception of lung cancer." As a result, she concluded, "the additional need for earlier detection and treatment will foreseeably not decrease in the years to come."
The work was supported by the National Institutes of Health, the American Cancer Society, and a Whitaker grant from MIT.
A version of this article appeared in the November 4, 1992 issue of MIT Tech Talk (Volume 37, Number 12).
