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.
Magic number colloidal clusters
13.12.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg
Record levels of mercury released by thawing permafrost in Canadian Arctic
13.12.2018 | University of Alberta
What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...
A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.
The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...
A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.
Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...
Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...
What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.
Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...
12.12.2018 | Event News
10.12.2018 | Event News
06.12.2018 | Event News
13.12.2018 | Life Sciences
13.12.2018 | Physics and Astronomy
13.12.2018 | Earth Sciences