Cancer is undoubtedly one of the greatest risks in the Ataxia Telangiectasia, in fact, second to lung infections.
About ¼ of people with AT develop cancer, the risk increasing with age.
The incidence of cancer is also higher in families of patients with AT.
Cancer
"Cancer" includes a large number of diseases that are sometimes expressed in a visible way: skin, growing tumors ..., but not always: cancer affecting blood cells by the bone marrow in an organ (lung, bone) before symptoms appear. But they all have some common points:
- Everyone is not equal in front of cancer: development of cancer depends on the genetic material of each individual. This explains the hereditary factor and the presence in families of a single type of cancer.
- Environment and exposure to risk factors are also highly contributory factors (cigarettes, pollutants, radiation ...).
- On a "healthy" subject, the development of cancer can take decades. The progressive weakening of the body's defenses can explain it.
- All cancers are degeneration of cells that are not recognized as such by the immune system and thus can proliferate, increasingly altering the functioning of the body.
Process in AT
In the chapter "The ATM gene", it has been described the process which, during the cell cycle, allows in the body of patients with AT the multiplication of abnormal cells after double-strand breaks in DNA.
This corresponds perfectly to the definition of a cancer and explains the cancer cases observed among them: stomach, brain, ovaries, skin, liver, larynx, lung and parotid gland (the largest of the salivary glands).
In the vast majority of cases, cancers in patients with AT are leukemia ou des lymphoma, cancers of the immune system.
Cancers in families of children with AT
A heterozygote is a healthy carrier of a defective allele (an individual has two alleles, ie two copies of each gene). We, parents of children with ataxia telangiectasia, are heterozygous for a mutation in the ATM gene.
By the late 80s, researchers note that heterozygotes for mutations in ATM (parents, aunts and uncles, grandfathers, grandmothers, cousins, etc ...) have abnormally high cancer rates, breast cancer being the highest. But every study on the subject has its share of inaccuracies and their results do not get to a clear idea.
For this reason, in June 2003, a team of INSERM led by Prof. Dominique Stoppa-Lyonnet launches a study in France, as part of a large-scale international study on breast cancer and over a significant period of several years. This study is called CoF-AT
Outlook
We parents can do something for once just by preserving factors known to promote these conditions.
Of course, the sensitivity of people with AT to commonly used techniques in the fight against cancer, chemotherapy and radiotherapy, limits potential treatments. But it does not mean that treating cancer is impossible, far from that.
In reality, these treatments do not satisfy the researchers because they are not specific enough and cause damage to healthy parts of the body which is already weakened by the cancer itself, even if it is less and less true with new treatments. It's almost as if to catch a criminal for sure, the police fired into the crowd.
Many other more accurate ways are being considered (see Research), such as with stem cells, genetically modified viruses, nanoparticles ...
And since our children are hypersensitive to cancer, since the ATM gene is central to certain cancer process, then it is interesting for the research against cancer and by extension, against Ataxia Telangiectasia.
