A Canadian team led by Wan L Lam and Stephen Lam from the BC Cancer Agency, took samples from the lungs of 24 current and former smokers, as well as from non-smokers who have never smoked. They used these lung samples to create libraries using a technique called serial analysis of gene expression (SAGE), which helps to identify patterns of gene activity.
Only about a fifth of the genes in a cell are switched on at any given time, but environmental changes such as smoking lead to changes in gene activity. The researchers found changes that were irreversible, and some changes that were reversed by stopping smoking. The reversible genes were particularly involved in xenobiotic functions (managing chemicals not produced in the body), nucleotide metabolism and mucus secretion. Some DNA repair genes are irreversibly damaged by smoking, and smoking also switched off genes that help combat lung cancer development.
The researchers identified a number of genes not previously associated with smoking that are switched on in active smokers. One example is CABYR, a gene involved in helping sperm to swim and associated with brain tumours, which may have a ciliary function. The team also further investigated changes in genes involved in airway repair and regeneration, and within this group identified genes that fell into three categories following cessation of smoking: reversible (TFF3, encoding a structural component of mucus; CABYR, in it's newly discovered bronchial role), partially reversible (MUC5AC, a mucin gene) and irreversible (GSK3B, involved in COX2 regulation). These findings were tested against a second cohort of current, former and non-smokers.
"Those genes and functions which do not revert to normal levels upon smoking cessation may provide insight into why former smokers still maintain a risk of developing lung cancer," according to Raj Chari, first author of the study. The study is the largest human SAGE study reported to date, and also generated a large SAGE library for future research.
Tobacco smoking accounts for 85 percent of lung cancers, and former smokers account for half of those newly diagnosed with the disease.
Scientists spin artificial silk from whey protein
24.01.2017 | Deutsches Elektronen-Synchrotron DESY
Choreographing the microRNA-target dance
24.01.2017 | UT Southwestern Medical Center
A Swedish-German team of researchers has cleared up a key process for the artificial production of silk. With the help of the intense X-rays from DESY's...
For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.
According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
24.01.2017 | Physics and Astronomy
24.01.2017 | Life Sciences
24.01.2017 | Health and Medicine