British scientists have discovered two new tumor suppressor genes that could improve treatment for malignant melanoma, a deadly skin cancer.
"We've discovered new genes that are present in normal skin cells that block malignancy in melanoma cells," Professor Robert Newbold told a news conference.
Newbold and his colleagues at Brunel University near London found the genes by using sophisticated new techniques to transfer healthy genes directly into cancerous cells.
"We now know that by placing these genes into the cancer cell they stop malignant melanoma in its tracks," he said.
Tumor suppressor genes (TSG) stop the uncontrolled growth of cancer cells. P16 had already been identified as an important TSG in skin cancer. Newbold and his team have added two more.
The scientists not only identified the new genes but mapped the portions of chromosomes 9 and 10 where they are located. They do not yet know how the genes work but once they do it will uncover new targets for drugs to treat melanoma.
"We're opening the door to developing new therapies," said Newbold. "These two genes are involved in the transition to malignancy."
Malignant melanoma is the most life-threatening type of skin cancer and the most common cause of cancerous death among 25-29 year olds.
It is also one of the fastest growing cancers throughout the world, particularly in warm, sunny countries. Excessive exposure to damaging ultraviolet rays from the sun is a major risk factor.
The cancer usually starts as a small brown or black mark on the skin and is often confused with a mole. If caught in its early stage the disease can be cured. But malignant melanoma is so dangerous because it can spread very quickly to other parts of the body.
"These findings show that we have successfully identified at least one new gene on chromosome 9 and one on 10 which have the ability to stop the growth and development of malignant melanoma," said Newbold.
The research is published in the latest edition of Cancer Research magazine.
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