Genetic parallels found between lung development and lung cancerJuly 05, 2006For over 100 years, biologists have speculated that cancer growth shares common features with embryonic development. Researchers at Children's Hospital Boston now provide solid evidence for this idea, showing through gene-chip analyses and bioinformatics techniques that many genes that are differentially expressed (turned "up" or "down") during early embryonic lung development are also differentially expressed in lung cancer. More importantly, they show that gene-expression profiling can predict a lung cancer's prognosis, and that cancers whose gene expression pattern resembles gene expression during the earliest stages of lung development have the worst prognosis of all. "This confirms our earlier finding of the importance of normal organ development in understanding cancer," says Isaac Kohane, MD, PhD, director of the CHIP program and a co-author on the paper. "Our observations might translate into more accurate prognoses and help us identify mechanisms of cancer growth that can be therapeutically targeted." Lung cancer, the world's leading cause of cancer deaths, has many known subtypes, but it is commonly misclassified, delaying appropriate treatment. In addition, cancers within a subtype may vary in their aggressiveness. Seeking a better way to classify lung cancers, Hongye Liu, PhD, and colleagues in the Children's Hospital Informatics Program (CHIP) examined gene activity in tumors from 186 patients and compared it with the gene activity that occurs during normal embryonic lung development in mice. They also examined 17 samples of normal lung tissue. Starting with 3,500 genes known to be common to mice and humans, they identified 596 genes whose activity was altered both in lung tumors and during lung development. Using the natural trajectory of lung development as a framework, Liu and colleagues were able to predict survival in patients with adenocarcinoma (the most common type of lung cancer, and the only type for which they had survival data). Tumors with gene expression patterns most like those during very early lung development had the worst prognosis, while tumors with gene expression patterns resembling those seen late in lung development had the best prognosis. Even within a single adenocarcinoma subtype — stage I disease — survival times varied according to gene expression patterns. Gene expression patterns in normal lung tissue resembled those seen in late in lung development. "Before, the idea that cancer and organ development are related was not quantified or statistically significantly demonstrated," says Liu. "The development perspective gives us a new mechanism for understanding cancer." The researchers also found that one lung cancer subtype, carcinoid tumors, have a gene expression profile distinct from all the others. When biopsy specimens are examined, carcinoid looks very similar to small-cell lung cancer, and the two are often mistaken for each other, yet their life expectancy and optimal treatments are very different. "By molecular profiling, we can distinguish these two cancers," Liu says. In addition, focusing on the 100 genes with the greatest cancer/development correlation, Liu and colleagues found three groups of genes that are involved in biological pathways believed to be key in lung cancer development, and some of the genes showed potential as drug targets. Several genes had stem-cell-like characteristics. Liu's work builds on a 2004 study, in which Kohane and Alvin Kho, PhD (another co-investigator on Liu's study) showed that a pediatric brain tumor called medulloblastoma shares many common genetic features with the cerebellum in its earliest stages of development ( http://www.childrenshospital.org/newsroom/Site1339/mainpageS1339P1sublevel81.html ). Children's Hospital Boston |
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| Related Lung Development Current Events and Lung Development News Articles New genes for lung disease discovered Scientists have discovered five genetic variants that are associated with the health of the human lung. The research by an international consortium of 96 scientists from 63 centres in Europe and Australia sheds new light on the molecular basis of lung diseases. Exposure to both traffic, indoor pollutants puts some kids at higher risk for asthma later New research presents strong evidence that the "synergistic" effect of early-life exposure to both outdoor traffic-related pollution and indoor endotoxin causes more harm to developing lungs than one or the other exposure alone. Asthmatic children: Did mom use her pump during pregnancy? Expectant mothers who eschew asthma treatment during pregnancy heighten the risk transmitting the condition to their offspring, according to one of the largest studies of its kind published in the European Respiratory Journal. How to Make a Lung: Cell-Regeneration Molecules Essential Signals for Early Lung Development, Penn Study Finds A tissue-repair-and-regeneration pathway in the human body, including wound healing, is essential for the early lung to develop properly. LSUHSC shows for first time infant inhalation of ultrafine air pollution linked to adult lung disease Stephania Cormier, Ph.D., Associate Professor of Pharmacology at LSU Health Sciences Center New Orleans, has shown for the first time that early exposure to environmentally persistent free radicals (present in airborne ultrafine particulate matter) affects long-term lung function. Cancer researchers link DICER1 gene mutation to rare childhood cancer Research published today in Science Express from the journal Science demonstrates the first definitive link between mutations in the gene DICER1 and cancer. Top notch decisions in the developing airways bring insights into lung disease In the normal lung, the airways are lined by a balanced mixture of ciliated, secretory and neuroendocrine cells which perform functions as diverse as air humidification, detoxification, and clearance of environmental particles. Changes in gene may stunt lung development in children Mutations in a gene may cause poor lung development in children, making them more vulnerable to diseases such as chronic obstructive pulmonary disease (COPD) later in life, say researchers at the University of Pittsburgh Graduate School of Public Health and the German Research Center for Environmental Health. Gene variants may determine lung function and susceptibility to maternal smoking A tiny variation within a single gene can determine not only how quickly and well lungs grow and function in children and adolescents, but how susceptible those children will be to exposure to second-hand tobacco smoke, even in utero, according to researchers from the University of Southern California. Scientists show gene mutation may cause immature lungs in newborns Scientists have identified a gene critical to lung maturation in newborns and the production of surfactant, which lines lung tissues and prevents the lungs from collapsing. More Lung Development Current Events and Lung Development News Articles |
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