Cancer and mutations

People with Gorlin Syndrome have only 1 working copy of a gene involved in the “Sonic Hedgehog Signalling Pathway”; generally the gene called “patched – 1” (PTCH1), but sometimes another of the relevant genes. Most people have 2 working copies of each of these genes, but Gorlin Syndrome results when one copy of a relevant gene is mutated, from conception, in all our cells. You could say that all our cells are therefore just a single - mutation - away from having NO working copy of a vital gene; a gene that can be described as a “tumour suppressor” gene, because it acts to prevent our cells becoming malignant or forming tumours.

Genes occasionally mutate. This is directly relevant to cancer.

In basic biology courses, genetic mutations are generally discussed in the context of inheritance, where the mutation may be passed to descendants. In humans and many other species, only the cells in specialised parts of the organism will pass their genes to descendants. In humans, the ovaries of women and the testes of men contain cells that produce “gametes”: ova from women, and spermatozoa from men. Mutations in ova or spermatozoa are called “germ-line” mutations, because they may be passed to descendants (“germ” is old scientific jargon related to seeds and reproduction). Cells in the rest of our body also accumulate genetic mutations over our lifetime, when the DNA in those cells is damaged, but those are genetic mutations which are not passed to descendants; they will affect only a part of that person's body. Such mutations are called “somatic mutations”, because “somatikos” is Greek for “of the body”. Wikipedia has a brief article about this scientific term.

http://en.wikipedia.org/wiki/Somatic

Many cancers are thought to result from somatic mutations. Therefore, I want to help people living with Gorlin Syndrome to understand what somatic mutations are, and know how they can minimise the rate of somatic mutations in their own bodies and minimise the rate at which tumours begin.

How can we minimise genetic mutations?

Some of the factors causing genetic mutations are not able to be controlled by us. We can (and should) choose to minimise our exposure to UV and to “ionising radiation” such as X-rays, but all of our bodies naturally contain some radioactive atoms and we are exposed to radiation from rocks, bricks and cement, and from outer space (“cosmic rays”), so we cannot avoid all radiation – induced genetic mutations.

In addition, the cellular mechanisms that copy DNA during cell division are not 100% perfect, so occasional mistakes are made in copying genes. There are repair mechanisms operating to fix these errors in DNA replication, but sometimes they fail to correct all the errors, and the alteration in DNA is then copied as the cell multiplies. The mutation is perpetuated in cells derived from the original altered cell.

Since every cell in people living with GS already carries a mutation in a relevant gene, our risk (or rate) of tumour formation is higher than in most people. It is important that we do what we can to avoid a mutation in our single copy of the relevant gene, because loss of that sole copy will cause severe damage to the cell involved, and will generally lead to initiation of a tumour as the cell multiplies.

I will explain what I think we can do about this. What we eat and drink is worth considering.

First, do NOT smoke. Smoke contains carcinogenic molecules; molecules that promote cancer formation. Many increase the rate of genetic mutations. Secondly, diet is worth considering. In my opinion, it is common sense to do what we can to stay well.

Public health experts recommend that everyone should eat certain foods, to minimise risk of cancers. People living with Gorlin Syndrome especially need to do this; I am convinced that it is important and worthwhile. Diet is known to influence rates of tumour formation, and I think this effect will probably be more – obvious in Gorlin Syndrome than in the absence of Gorlin Syndrome, because we are so sensitive to carcinogenic agents. Eating plenty of antioxidant – rich foods will help our bodies prevent or repair the inevitable DNA damage that occurs as we age, even in areas of our bodies that are not exposed to extra radiation.

Green tea is sometimes promoted as a source of antioxidants. It was investigated years ago in the UK as an agent to slow down the rate of BCC formation in people with GS. It seems that "black" tea (that is, Ceylon / Indian style tea) also help to prevent BCCs; I am glad about this, because I drink a lot of “black tea” (with milk).

See this article from "Quarterly Advocate":

http://www.bccns.org/news/2007Summer.pdf

"As Published in Journal of the American Academy of Dermatology, May 2007

Tea Drinkers May Have Lower Skin Cancer Risk

People who unwind with a cup of tea every night may have a lower risk of two common forms of skin cancer, new research suggests. In a study of nearly 2,200 adults, researchers found that tea drinkers had a lower risk of developing squamous cell or basal cell carcinoma, the two most common forms of skin cancer. Men and women who had ever been regular tea drinkers -- having one or more cups a day -- were 20 percent to 30 percent less likely to develop the cancers than those who didn't drink tea. … … …"

It is good to know that tea has many good effects on my body, as well as being a refreshing daytime drink.

Red wine is another source of dietary antioxidants, but there are plenty of non-alcoholic choices; apparently, fruits and vegetables that are naturally coloured red, orange, yellow, purple or green are good sources, too.

I will discuss vitamin D in another post. In brief: take vitamin D, in a supplement!