Sunscreen Gene Found To Prevent Melanoma | Opens Doors To New Drug Discovery
Researchers at the University of Southern California (USC) have identified a “sunscreen gene” that may protect against the deadliest form of cancer- melanoma. They say the finding potentially could lead to new drugs to prevent the disease.
After using data from 340 melanoma patients, researchers found that melanoma patients with deficient or mutant copies of the “UV radiation Resistance Associated Gene” are less protected from harmful ultraviolet rays. The study also included two experimental groups with either reduced levels of UVRAG or a mutant copy of that gene in melanoma cells or 50 fly eyes, using normal UVRAG copies as controls.
The researchers subsequently gave a UV pulse to cells carrying the normal UVRAG and cells carrying defective copies of it. After 24 hours, cells carrying healthy versions of the gene had repaired more than 50% of the UV-induced damage. In contrast, the defective samples repaired less than 20% of the damaged cells.
UVRAG is involved in the multistep DNA cell repair process, researchers found. First a known protein scans for damaged DNA. Once it finds lesions, it tags the UV-resistant gene into action. The UV-resistant gene is
like a humanitarian convoy dropping off reinforcements or aid to help damaged areas repair at precisely the right time.Unfortunately, the research team did not have data from people without skin cancer, so they were unable to compare their observations of melanoma patients with those of skin cancer-free people.
“If we understand how this UV-resistant gene functions and the processes by which cells repair them after ultraviolet damage, then we could find targets for drugs to revert a misguided mechanism back to normal conditions,” said Chengyu Liang from University Of Southern California in the US. More than 90 per cent of melanoma skin cancers develop because of cell damage from exposure to UV radiation, researchers said.
“People who have the mutated UV-resistant gene or low levels of the UV-resistant gene may be at higher risk of melanoma or other skin cancers, especially if they go sunbathing or tanning frequently,” said Liang. “Our study suggests that the UV-resistant gene may serve as a biomarker for skin cancer prevention,” she said.
“We found the expression level of the UV-resistant gene is related to melanoma patients’ survival and metastasis stages,” Dr. Yang said. “Lower levels of the UV-resistant gene mean a lower survival rate and advanced metastases stages.”
“To our knowledge, the UV-resistant gene does not have any enzymatic activity; it’s a supporter or coordinator,” Dr. Liang added. “Although it may not be the direct doer, without it, the whole structure collapses.”
The investigators will conduct research with mice to learn more about how the UV-resistant gene functions. “The UV-resistant gene may serve as a good target for drug development,” said study author Yongfei Yang, a research associate at Keck.
Perhaps one day a drug could stimulate the repair function of the UV-resistant gene to ensure swift and effective repair of UV-damaged skin cells, Yang said. “That would be a good treatment for people who are at high risk of developing skin cancer,” the researcher concluded.
The findings were published in the journal Molecular Cell.
