Discovery of potential biomarker for smoking-related lung diseases



Researchers from Duke University Medical Center have identified a variation in a particular gene that increases susceptibility to early coronary artery disease. For years, scientists have known that the devastating, early-onset form of the disease was inherited, but they knew little about the gene(s) responsible until now. The results are published January 2 in the

Full Post: Neuropeptide Y gene variation may lead to early coronary artery disease

Researchers from Boston University School of Medicine (BUSM) have demonstrated that a recently discovered class of molecule called microRNA (miRNAs), regulate the gene expression changes in airway cells that occur with smoking and lung cancer.

These findings, which appear in the on-line early edition of journal Proceedings of the National Academy of Sciences, may lead to a new, relatively non-invasive biomarker for smoking-related lung diseases.

Approximately 1.3 billion people smoke cigarettes worldwide, which contributes to five million preventable deaths per year. Smoking is a significant risk factor for lung cancer, the leading cause of cancer death in the United States and the world, with more than one million deaths worldwide annually. Eighty-five to 90 percent of subjects with lung cancer in the United States are current or former smokers with 10 to 20 percent of heavy smokers developing this disease. Because of the lack of effective diagnostic biomarkers and the inability to identify which current and former smokers are at greatest risk, lung cancer is most often diagnosed at a late stage where current therapies are largely ineffective.

A previous study by the same researchers reported a gene expression biomarker capable of distinguishing cytologically normal bronchial airway epithelial cells from smokers with and without lung cancer, serving as an early diagnostic biomarker for lung cancer. The importance of this “field-of-injury” concept is that it allows for the detection of lung cancer in tissues that are more readily sampled than the diseased lung tissue itself. In this study, the researchers profiled the miRNAs in these readily accessible airway epithelial cells and identified those that are differentially expressed with smoking.

Studying current and non-smokers, the researchers examined whole-genome miRNA and mRNA expression in bronchial airway epithelial brushings obtained at bronchoscopy and found 28 miRNAs to be differentially expressed in the majority of smokers. In addition, the researchers showed that by modulating the expression of one such miRNA (mir-218), it was sufficient to alter the expression of a subset of the mRNAs that are both predicted targets of this miRNA and altered by smoking in vivo.

“These studies suggest that smoking-dependent changes in miRNA expression levels mediate some of the smoking induced gene expression changes in airway epithelium and that miRNAs therefore play a role in the host response to environmental exposures and may contribute to the pathogenesis of smoking-related lung cancer,” said senior author Avrum Spira, MD, an associate professor of medicine and pathology at BUSM.

According to the researchers, it is hoped that miRNA profiles obtained from these cells may serve as relatively non-invasive biomarkers for smoking-related lung diseases.

“These microRNA changes may serve as more robust biomarkers in clinical samples given their role as regulators of multiple mRNAs and their relative resistance to degradation,” said first author Frank Schembri, MD, an assistant professor of medicine at BUSM.

http://www.bu.edu/

Link




Canadian researchers are trying to answer why some smokers develop lung cancer while others remain disease free, despite similar lifestyle changes. Results were presented at the American Association for Cancer Research’s Seventh Annual International Conference on Frontiers in Cancer Prevention Research. According to the Centers for Disease Control and Prevention, more people die from lung

Full Post: Why only some former smokers develop lung cancer



The association between tobacco smoke and cancer deaths - beyond lung cancer deaths - has been strengthened by a recent study from a UC Davis researcher, suggesting that increased tobacco control efforts could save more lives than previously estimated. The epidemiological analysis, published online in BMC Cancer, linked smoking to more than 70 percent of the cancer

Full Post: Study links smoking with most male cancer deaths



An analysis of previous studies indicates that smoking is significantly associated with an increased risk for colorectal cancer and death, according to an article in the December 17 issue of JAMA, the Journal of the American Medical Association. Although tobacco was responsible for approximately 5.4 million deaths in 2005, there are still an estimated 1.3

Full Post: Smoking significantly linked to increased risk for colorectal cancer



In a new analysis of tissue biomarkers expressed in ovarian cancer samples, published by PLoS Medicine, David Huntsman and his colleagues from Vancouver General Hospital suggest that substantial differences exist between ovarian cancer subtypes which should be reflected in patient management. Although ovarian cancer is not the most common gynecologic cancer in women, the disease

Full Post: Analysis of tissue biomarkers expressed in ovarian cancer samples



Just seeing someone smoke can trigger smokers to abandon their nascent efforts to kick the habit, according to new research conducted at Duke University Medical Center. Brain scans taken during normal smoking activity and 24 hours after quitting show there is a marked increase in a particular kind of brain activity when quitters see photographs

Full Post: Why stopping smoking is hard