Why don't we get cancer all the time?

Dec 19, 2007

The seemingly inefficient way our bodies replace worn-out cells is a defense against cancer, according to new research.

Having the neighboring cell just split into two identical daughter cells would seem to be the simplest way to keep bodies from falling apart.

However that would be a recipe for uncontrolled growth, said John W. Pepper of The University of Arizona in Tucson.

"If there were only one cell type in the group, it would act like an evolving population of cells. Individual cells would get better and better at surviving and reproducing," said Pepper, a UA assistant professor of ecology and evolutionary biology and a member of UA's BIO5 Institute.

"When cells reach the point where they divide constantly, instead of only when needed, they are cancer cells."

Instead, multicellular organisms use a seemingly inefficient process to replace lost cells, Pepper said. An organ such as the skin calls upon skin-specific stem cells to produce intermediate cells that in turn produce skin cells.

Although great at their job, the new skin cells are evolutionary dead ends. The cells cannot reproduce.

Losing the ability to reproduce was part of the evolutionary path single-celled organisms had to take to become multicellular, Pepper said.

What was in it for the single cells?

"Probably they got to be part of something more powerful," Pepper said. "Something that was hard to eat and good at eating other things."

Pepper and his colleagues published their paper, "Animal Cell Differentiation Patterns Suppress Somatic Evolution," in the current issue of PLoS Computational Biology. Pepper's co-authors are Kathleen Sprouffske of the University of Pennsylvania in Philadelphia and the Wistar Institute in Philadelphia and Carlo C. Maley of the Wistar Institute.

The National Institutes of Health, the Pennsylvania Department of Health, the Pew Charitable Trust and the Santa Fe Institute funded the research.

Pepper became curious about the origins of cooperation between cells while he was a postdoctoral fellow at the Santa Fe Institute in New Mexico.

"Organisms are just a bunch of cells," he said.

"If you understand the conditions under which they cooperate, you can understand the conditions under which cooperation breaks down. Cancer is a breakdown of cooperation."

Pepper and his colleagues used a kind of computer model called an agent-based model to compare different modes of cellular reproduction.

The results indicate that if cells reproduce by simply making carbon-copies of themselves, the cells' descendants are more likely to accumulate mutations.

In contrast, if cellular reproduction was much more complicated, the cells' descendants had fewer mutations.

Suppressing mutations that might fuel uncontrolled growth of cells would be particularly important for larger organisms that had long lives, the team wrote in their research report.

Source: University of Arizona

Explore further: Pain and itch may be signs of skin cancer

add to favorites email to friend print save as pdf

Related Stories

Exploring the inner workings of materials

Nov 02, 2011

Growing up in an “idyllic” area of farms and orchards in southern New Jersey, Krystyn Van Vliet had little exposure to science or technology. And yet, it was that very environment that she credits with kindling ...

Novel compound selectively kills cancer cells

Jul 13, 2011

A cancer cell may seem out of control, growing wildly and breaking all the rules of orderly cell life and death. But amid the seeming chaos there is a balance between a cancer cell's revved-up metabolism and skyrocketing ...

Study reveals capsaicin can act as cocarcinogen

Sep 02, 2010

The September cover story of the nation's leading cancer journal, Cancer Research, features a new study from The Hormel Institute, University of Minnesota, that links capsaicin, a component of chili peppers, to skin cancer ...

Scientists learn to block pain at its source

Apr 26, 2010

A substance similar to capsaicin, which gives chili peppers their heat, is generated at the site of pain in the human body. Scientists at The University of Texas Health Science Center at San Antonio have discovered how to ...

Recommended for you

Incomplete HPV vaccination may offer some protection

6 hours ago

Minority women who received the Human Papillomavirus Vaccination (HPV) even after becoming sexually active had lower rates of abnormal Pap test results than those who were never vaccinated. These findings appear in the journal ...

New imaging agent provides better picture of the gut

6 hours ago

A multi-institutional team of researchers has developed a new nanoscale agent for imaging the gastrointestinal (GI) tract. This safe, noninvasive method for assessing the function and properties of the GI tract in real time ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

enantiomer2000
1 / 5 (1) Dec 19, 2007
"Organisms are just a bunch of cells,"

nothing new to see here people, move along...