Researchers at the University
of Padova in Italy have identified
a possible link between melanoma, the most severe type of skin cancer, and the gene
for the vitamin D receptor. They reviewed several studies that looked at the
association between the risk for melanoma and common variants of the vitamin G
receptor gene called BsmI. The University
of Padova team found
people with variants in a Vitamin D gene, called BsmI, had an increased risk
for the disease.
“These findings prompt further
investigation on this subject and indirectly support the hypothesis that sun
exposure might have an anti-melanoma effect through activation of the vitamin D
system,” the researchers wrote in the study published in the Nov. 1 issue of the
journal Cancer.
Data from six studies, which included a
total of 2,152 patients who had melanoma and 2,410 subjects that did not have
the cancer, were included in the analysis, Reuters notes. The studies looked at
the impact of five vitamin G receptor gene variants designated TaqI, FokI,
BsmI, EcoRV, and Cdx2, on the risk of melanoma.
They found people who had an increased risk
of melanoma had variants in a vitamin D gene called BsmI. Dr. Simone Mocellin
and Dr. Donato Nitti, from the University
of Padua reported that
Patients with the BsmI variant had a 30 % increased risk of melanoma. This will
account for close to 10 percent of melanoma cases. The impact of the other
variants was less clear.
The recent study represents the first combined
analysis performed using published data, according to the report in the journal
Cancer.
A study by the National Institute of Cancer
found a 50 percent increase in the annual incidence of melanoma among young
women. The main risk factor for developing melanoma is ultraviolet radiation.
Contrary to other studies which say that sunscreen
can even increase the melanoma risk, the study’s authors concluded that although
the effects of BsmI variant are not fully known, the findings indirectly
support the theory that sun exposure may have anti-cancer effects.
“Current evidence is in favor of the
association between one [vitamin D receptor] gene polymorphism and the risk of
melanoma development, although further work will be necessary to validate the
risk identified in the current meta-analysis,” the authors wrote. They also
said that a significant limitation of the analysis is the fact that the results
could not be adjusted by patient characteristics, environmental factors or any
other melanoma risk factors (e. g. phototype, a family history of melanoma).
According to the American Academy
of Dermatology, more than 1 million new cases of skin cancer are diagnosed each
year. About 62,480 people in the U.S. will be diagnosed with
melanoma in 2008. About 48,000 melanoma related deaths occur worldwide each
year and around 160,000 new cases of melanoma are diagnosed worldwide each
year. The malignant tumor of melanocytes which are found predominantly in the
skin accounts for 75 percent of deaths associated with skin cancer.
