The Origins of Cancer: Scientists Target Tumor Development

Tumors develop through a variety of processes. Now, though, researchers have created the first comprehensive compendium of mutational processes that drive this development. In fact, these listed processes explain most mutations found in 30 of the most common cancer types, paving the way to treating and preventing cancers.

All cancers are caused by mutations in DNA in the cells of a person's body. While researchers know that certain environmental factors, such as tobacco smoke and ultraviolet light, can cause these mutations, scientists still have remarkably little understanding of the biological processes that cause the mutations which are responsible for the development of most cancers.

In order to examine the mutational process of tumors, the researchers studied 7,042 genomes of people with the most common forms of cancer. All of the cancers were found to contain two or more signatures, reflecting the variety of processes that work together during the development of cancer. Yet different cancers have different numbers of mutational processes. For example, two mutational processes underlie the development of ovarian cancer, while six underlie the development of liver cancer.

"We have identified the majority of the mutational signatures that explain the genetic development and history of cancers in patients," said Ludmil Alexandrov, one of the researchers, in a news release. "We are now beginning to understand the complicated biological processes that occur over time and leave these residual mutational signatures on cancer genomes."

The researchers also found that some of the mutational signatures are in multiple cancer types. Others, on the other hand, are confined to a single cancer type. Out of the 30 cancer types, 25 had signatures arising from age-related mutational processes.

"Through detailed analysis, we can start to use the overwhelming amounts of information buried deep in the DNA of cancers to our advantage in terms of understanding how and why cancers arise," said Serena Nik-Zainal, one of the researchers, in a news release. "Our map of the events that cause the majority of cancers in humans is an important step to discovering the processes that drive cancer formation."

The findings could allow researchers to better treat cancers and tumors in the future. By understanding the processes behind their formation, it's possible that scientists could prevent these processes in the first place through treatment.

The findings are published in the journal Nature.

Want to learn more about the research? Check out the video below, courtesy of YouTube.