New research: One to ten mutations are needed to start a cancer

One to ten mutations in the genes present in a cell are average enough to initiate a cancer, according to a new British scientific study. But the number of required genetic mutations differs greatly between different types of cancer.

For the first time, scientists have in their hands confirmed estimates of the number of mutations that "trigger" a cancer, having genetically analyzed over 7,600 volumes of 29 different types of cancer. 

The researchers, led by Dr Peter Campbell, of the Wellcome Trust Sanger Institute, who published the journal Cell Cell Biology, also recorded the major genes responsible for cancer and, on the way, they discovered several new "guilty" genes - while many more are expected to be discovered in the future. 

"We have responded to a long-standing question in cancer research, which has been in the hands of scientists since the 1950s: how many mutations are needed in a normal cell to become cancerous. The answer is:very few, "Campbell said.

But there are significant differences. For example, only one mutation is enough for a thyroid or testicular cancer, four average mutations per patient are sufficient to initiate liver or breast cancer, and for colon cancers it usually requires around ten mutations . 

Another notable finding of the new research is that cancerous mutations are usually well tolerated by the cells of the body. Instead, the mutations that one inherits from his parents are often not tolerated and lost by the human species over time. However, as cancer develops in the cells of the body, almost all mutations are retained.

It has also been found that about half of the key mutations that trigger cancer occur in genes that were never previously thought to be cancerous genes. Scientists now believe that in the future they will discover many more genes that, after mutation, are involved in cancer. 

Research such as this is an important step forward in identifying those specific - and possibly different for each human - mutations responsible for a cancer among the thousands of other mutations found in each tumor. This will definitely contribute to more personalized and more effective anti-cancer therapies.