Nuclear Oncology

Posts Tagged ‘Cancer’

Research explains how some cancer-causing virus
According to the results of a study published in Genome Research, led by Manel Esteller, director of the Epigenetics and Biology as the results of a study published in Genome Research, led by Manel Esteller, director of the Epigenetics and Cancer Biology Biomedical Research Institute (IDIBELL) and the Catalan Institute of Oncology (ICO) and ICREA researcher, says that 15% of cancer cases are related to a virus. But not all infected people eventually develop a malignancy. The malignant process is initiated in cases where the pathogen is able to modify their own genetic material to outwit the body’s defenses.

Researchers have analyzed over 500 samples of infected tissue by leading oncogenic viruses: human papilloma virus, necessary cause for cervical cancer development, the hepatitis B virus, related to the occurrence of liver cancer, and Epstein-Barr virus, the cause of some types of lymphoma. They have been collected in three population groups: individuals infected but not symptomatic, people who have developed an infection or a premalignant lesion, and people who have already developed a tumor or cancer associated.
In each of these stages, the genetic material of the virus undergoes important changes in the epigenome. That is, the pattern of chemical signals, a kind of switches, which makes their genes (genome) are expressed or not. Methylation of the disabled, and acetylation activates them. “When the virus enters the body, in the early stages of infection, is expressed in all their genes because it is not methylated. So the immune system can detect and remove it,” says Esteller.
But little by little, the virus manages to evade the immune system. As the infection progresses to a premalignant state, the virus will be more methylated, which means that their genes are expressed and leaving, therefore, the immune system is costing you more and more detect and attack, says Esteller. The virus achieves this state by robbing the host cell proteins. The uses to weave a garment with which biochemical immune camouflage. However, not hiding his viral load, which is still active. When the malignant tumor appears, the virus has not only fully camouflaged, but the gene has also been plundering modify the behavior of the cell and turn it into a carcinogen.
What makes these viruses increase their ability to deceive? To get an accurate answer still need more research, but there are indications that on the one hand individual genetic differences influence. And secondly, there are studies that indicate that some environmental exposures facilitate methylation. This is the case of exposure to snuff, high radiation doses or excesses with the sun, says Esteller. Bad habits not only alter the epigenetics of the virus, but also weaken the immune system and allows the virus to penetrate better into the cell. In fact, when it detects the presence of hepatitis B and C drugs are used to enhance immune system activity. In the case of papilloma virus (HPV), yet there is no effective treatment to destroy it, but you are advised to exercise extreme healthy habits for the immune system to defend itself in the most effective and runs with it, explains Silvia Sanjose, responsible Unit infections and cancer of the ICO. In women, HPV accounts for about 55% of tumors associated with infections.
According to both experts, knowing the epigenetics of these viruses will develop treatments that prevent the methylation, ie they prevent the virus robs its host cell proteins to trick the immune system. Esteller believes that these alterations may also be present in other viruses responsible for diseases such as influenza and AIDS.
Other research shows that not only inherits the genome, but also its pattern of activation, the epigenome. “We believe the epigenome altered by toxic habits could also be inherited,” he concludes.

Quit smoking to avoid cancer in the future

Two studies reveal more benefits if you quit smoking. One of them, published in the journal Proceedings of the National Academy of Sciences’ (PNAS), presents a new statistical model to predict mortality of men and women between 2004 and 2034. With this tool, the authors conclude that when leaving the snuff, the decline in the mortality rate is faster than previously thought.

Thus, taking into account the rate at which society is quitting smoking, estimate that by 2034, men between 50 and 85 years are 22.5% more likely to live than they had in 2004. This percentage drops to 7.4% in the case of females, who are less firm in making the decision to quit smoking.

The novelty is that the model takes into account the years he has been smoking the individual when they turn 40 instead of the number of cigarettes consumed. “The time it takes to smoke, rather than the intensity of smoking is a much more effective variable to predict the risk of death from lung cancer are smokers,” says study coordinator, Samuel Preston, University of Pennsylvania , United States.

The other study, published in the journal ‘Pediatrics’, identifies a new risk of snuff affects nonsmokers. This is the ‘third hand smoke’, a term that doctors have devised a Children’s Hospital Boston MassGeneral to refer to the harmful particles that remain in clothing and carpets, which are harmful, especially for children.

Parents who smoke often open windows or calm your craving for nicotine in rooms where children are not to avoid the harmful effects of secondhand smoke, also called “secondhand smoke”. However, they are not aware that in the cushions, carpets, clothes and even hair cigars are waste, including heavy metals, carcinogenic particles and other harmful materials.