Melanoma is linked to Obesity Gene
A study published in Nature Genetics demonstrates that a major risk factor for malignant melanoma is obesity. Although it is the least common of all skin cancers, melanoma has the highest mortality rate of all skin cancers, that is responsible for approximately 80% of all skin cancer deaths. In UK melanoma is the fifth most common cause of death.
Malignant melanoma is a tumor that develops by proliferation of melanocytes, cells that are found between the two skin layers: epidermis and dermis. Among causative factors of melanoma, genetics has an important role. There are several melanoma associated genes: CDKN2A (p16), CDK4, RB1, CDKN2A (p19), PTEN/MMAC1. There are also mutations that run in families and in this case the risk of developing this type of skin cancer is higher. Melanoma can arise from preexisting lesions such as moles and signs that are suggestive for malignancy are systematized by ABCDE: asymmetry, irregular borders, change in color, diameter over 6 mm and elevation. Another important risk factor for melanoma, besides genetic factors, is exposure to sunlight. Studies have shown that sun exposure leads to skin immune system suppression, production of free radicals and DNA alteration.
Treatment of choice consists of surgical excision of melanoma with oncological safety margins and lymphadenectomy. Surgery is completed by chemotherapy and radiotherapy. The prognosis depends on many factors such as tumor stage (thickness), the invasion, type of melanoma, etc.. However survival at 5 years is less than 10%.
The study led by researchers at the University of Leeds is the first to reveal that could be a link between obesity and melanoma. To reach these conclusions, the researchers investigated 13,000 patients with melanoma and 60,000 healthy individuals worldwide. It seems that the FTO gene mutations lead to obesity and overeating and are associated with increased BMI (body mass index). A high BMI means obesity, and obesity is a risk factor for many diseases such as diabetes, heart disease, cancer and other types. Study author, Dr Mark Iles, Cancer Research UK scientist at the University of Leeds, said it is the first time this gene (FTO) that has already been associated with many diseases, has been involved in melanoma. He said it is possible that in the future to discover that this gene is involved in other diseases.
Dr Julie Sharp, Cancer Research UK’s senior science information manager, mentioned that this research may lead to the discovery of therapeutic targets and of new drugs for treating melanoma.