When there is an abnormal cell growth in the lungs, it leads to lung cancer. Lung cancer is often caused due to smoking, but is not restricted to it alone. Usually there are no signs or symptoms to identify lung cancer, but coughing, shortness of breath and wheezing may appear in advanced stages of cancer. Treatment includes radiation, chemotherapy and surgery.
Lung cancer is identified as one of the deadliest type of cancer which occurs in both men as well as women. It is more common in older people than those under 45 years of age. A leading cause of this cancer is cigarette smoking. Second hand smoke (breathing of other’s cigarette smoke) too increases risk of lung cancer. Other causes include;
- Exposure to substances associated with cancer such as beryllium, uranium, vinyl chloride, coal products, asbestos, gasoline and diesel exhaust.
- High arsenic levels in drinking water
- Air pollution
- Radon gas
New studies carried out by international scientists identify 3 genetic regions which make non- smoking Asian women predisposed to Lung cancer. The findings of this research further indicate that risk of non-smoking Asian women to lung cancer is associated with unique genetic characteristics that separate them from lung cancers in smokers.
The 7th leading cause of cancer related death of never-smokers in the entire globe is attributed to lung cancer. Majority of lung cancers diagnosed in women in Eastern Asia are never-smokers. Although varied factors such as second hand smoke, exhaust smoke from cooking also amount to lung cancer amongst Asian women, they form a very small proportion of disease. In order to gain better understanding regarding lung cancer in Asian women who have never smoked, National Cancer Institute researchers, in collaboration with researchers from several other countries created the Female Lung Cancer Consortium in Asia to conduct a large Genome-Wide Association Studies (GWAS) in never-smoker ladies. It compares the DNA markers across the genome of people with the disease to those of without the disease. This is the largest GWAS study regarding lung cancer carried in the entire world said the senior investigator and leader of the study, Qing Lan, M.D., Ph.D.
The findings of the consortium were reported in Nature and Genetics, online on November 2012. The GWAS combined data from 14 studies which included data of approximately 14,000 Asian women, out of which 6,600 had lung cancer whereas 7,500 did not suffer from lung cancer. The study also took into account environmental factors such as exposure to secondhand smoke.
The conglomerate was able to find that in the genome variations at 3 locations, 2 on the chromosome 6 and 1 on the chromosome 10, were the cause of lung cancer in Asian women who never smoked. Out of these discoveries, chromosome 10 discovery was very important as it had never been found in any other GWAS of lung cancer in any race of women.
According to Nathaniel Rothman. M.D, senior investigator at NCI’s Division of Cancer Epidemiology and Genetics, the study has given strong evidence that inherited genetic variation play an important role in increasing lung cancer risk. These variants may also cause increased risk of lung cancer that is associated with environmental factors.
One important discovery made in this study is that there was no association with chromosome 15 variation that has been associated with lung cancer in smoking population. This thus establishes the fact that since there is no association, the chromosome 15 variation is smoking related. Another discovery made was that those Asian women with the newly identified genetic variant are more susceptible to environmental tobacco smoke effects, although more research is required in this sphere.
This study has been an important one in identifying susceptibility of Asian women and how gene variation can cause this susceptibility. It is another step in future that will help to fight the deadliest of cancer effectively.
Michelle Tyler is a freelance healthcare writer with more than 10 years experience in the healthcare communications field. A Certified Medical Assistant, she works with the Local Media group to research and report on the latest medical breakthroughs.
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