Tom Murphy
RedwoodAge.com
Leafy green vegetables and multivitamins may help ward off lung cancer in smokers, according to a new study.
Researchers at the Lovelace Respiratory Research Institute in Albuquerque found substances in the veggies and some vitamins may influence a process called gene methylation. Other research has linked that process to lung cancer.
The findings extend on ongoing debate in the medical community about links between diet and cancer. Some past studies have shown smokers who took beta-carotene supplements actually had an increased risk of lung cancer. This study showed reduced risk, but from a different set of food supplements.
Methyls are four-atom molecules and can affect the way genes act. For example, genes involved in cell division are "methylated" in lung tumors, according to the study led by Dr. Steven Belinsky.
The Albuquerque team, whose work was supported by the National Cancer Institute and the National Institutes of Health, looked at sputum from 1,100 current and former smokers who also filled out detailed questionnaires about diet. About three-quarters of the participants were women.
The researchers look at the methylation in eight genes linked to lung cancer, then compared the results to 21 dietary variables. They found people eating leafy green vegetables and taking folate had a lower probability of methylation.
Those who took multivitamins rich in chemicals found in leafy green
vegetables also had less gene methylation. Those chemicals include vitamins A, C
and K, carotenoids, lutein and folic acid.
"Aberrant gene methylation is a known mechanism in the development of
cancer from cigarette smoke carcinogens," said Dr. Jacob Kagan of the
Cancer Biomarkers Research Group in NCI's Division of Cancer Prevention.
Preventing Cancer
The researchers think gene methylation is a promising way of predicting lung
cancer so that doctors can intervene earlier through detection and early
chemical treatment. They also think prevention techniques may follow that will
include dietary changes.
"Additional research is needed to independently validate the current observations, and also to help resolve contradictions between varying studies," said Dr. Sudhir Srivastava, chief of the Biomarkers Research Group at the cancer institute. "Such studies are important steps for the future success of chemopreventive strategies."
