June 30, 2011

Order of Cancerous Mutations Identified

(Ivanhoe Newswire) "“ A key for early diagnosis of cancer and personalized medicine is the order of genetic aberrations - deviations or irregularity - in individual cancers. Now, scientists have begun to reveal the order of mutations that lead to cancer.

"We know that each cancer is a collection of genetic malfunctions," Raymond Cho, Ph.D., assistant clinical professor in the department of dermatology at the University of California, San Francisco, was quoted as saying.

"We now know it is possible to determine which changes happen earlier and which ones happen further down the road, even in a single cancer."

The researchers focused on TP53, a known oncogene, which is a gene that has the potential to cause cancer. TP53 is present in cutaneous squamous cell carcinomas and serous ovarian adenocarcinomas. By examining how additional copies of the mutant oncogene accumulated, they found that complex changes in TP53 occurred earlier in most cases, rather than later, as had been previously believed.

The ability to identify the actual sequence of mutations will help scientists to determine which mutations lead to precancerous lesions and which produce invasive carcinomas, which are cancers that begin in a tissue that lines the inner or outer surfaces of the body.

"Although cancers carry many mutations, the ones that always happen earliest set the stage for additional abnormalities," said Dr. Cho.

SOURCE: Cancer Discovery, June 29, 2011