Nav: Home

How the immune system protects us against bowel cancer

January 31, 2019

Researchers from Charité - Universitätsmedizin Berlin have discovered a protective mechanism which is used by the body to protect intestinal stem cells from turning cancerous. The body's innate immune system was found to play a pivotal role in this regard. The researchers were able to demonstrate that, rather than having a purely defensive role, the immune system is crucial in maintaining a healthy body. The study has been published in the renowned scientific journal Nature*.

Inside our bowels, there is a meeting of two worlds. It is where the cells of our intestinal cell walls meet foreign materials, such as bacteria, foodstuffs, and the breakdown products of digestion. Both of these worlds - that of our bodies and that of the outside world - are in direct contact, continually exchanging information. This direct contact is of crucial importance to our bodies, as many of the environmental factors we are exposed to (such as certain types of bacteria or essential nutrients) are beneficial or even vital to our health. However, contact with the environment can also have a negative impact on our bodies. Certain foreign substances, for instance, can trigger genetic changes inside the epithelial cells which line our intestinal walls. The accumulation of this type of DNA damage, particularly when it occurs inside epithelial stem cells, can lead to bowel cancer.

To prevent this progression to cancer, cells have the capacity to repair DNA damage. Where damage is too extensive, they can commit 'altruistic cell suicide' (also known as apoptosis). Until now, scientists had assumed that stem cells triggered this repair mechanism independently. However, the study (led by Prof. Dr. Andreas Diefenbach, Director of Charité's Institute of Microbiology, Infectious Diseases and Immunology, BIH-Professor in Precision Medicine and Head of the Mucosal Immunology Research Group at the German Rheumatism Research Center) comes to a different conclusion, namely that the immune system is capable of enhancing the DNA repair mechanism in damaged stem cells, thus preventing progression to bowel cancer.

Working with other researchers, Prof. Diefenbach and his team were able to show in a mouse model that cells of the innate immune system are capable of recognizing genotoxic environmental factors present in the bowel. Among these are certain glucosinolates, natural components of plants which are commonly found in many types of cabbage. Once the cells of the innate immune system detect damaging glucosinolates, they send out interleukin 22, a type of cellular messenger. This, in turn, enables the epithelial stem cells to detect potential DNA damage earlier and repair it faster. "The immune system acts like a sensor that detects genotoxic food components," explains Prof. Diefenbach. "Switching off this sensor results in a significant increase in cases of bowel cancer."

For the immunologist, these findings are not only evidence of a previously unknown regulatory system which is used by the body to protect itself against bowel cancer. It is also evidence of the fact that the immune system's functions are far more complex than that of a simple defense mechanism against pathogens. "The immune system monitors both the healthy growth and function of different organs in the body," explains Prof. Diefenbach. He and his team would like to use future research studies to explore the complex interaction between food components, intestinal flora, the intestinal wall and the immune system in greater detail. "It is here that we may find the key to why there are so many inflammatory disorders," says Prof. Diefenbach.
-end-


Charité - Universitätsmedizin Berlin

Related Cancer Articles:

Stress in cervical cancer patients associated with higher risk of cancer-specific mortality
Psychological stress was associated with a higher risk of cancer-specific mortality in women diagnosed with cervical cancer.
Cancer-sniffing dogs 97% accurate in identifying lung cancer, according to study in JAOA
The next step will be to further fractionate the samples based on chemical and physical properties, presenting them back to the dogs until the specific biomarkers for each cancer are identified.
Moffitt Cancer Center researchers identify one way T cell function may fail in cancer
Moffitt Cancer Center researchers have discovered a mechanism by which one type of immune cell, CD8+ T cells, can become dysfunctional, impeding its ability to seek and kill cancer cells.
More cancer survivors, fewer cancer specialists point to challenge in meeting care needs
An aging population, a growing number of cancer survivors, and a projected shortage of cancer care providers will result in a challenge in delivering the care for cancer survivors in the United States if systemic changes are not made.
New cancer vaccine platform a potential tool for efficacious targeted cancer therapy
Researchers at the University of Helsinki have discovered a solution in the form of a cancer vaccine platform for improving the efficacy of oncolytic viruses used in cancer treatment.
American Cancer Society outlines blueprint for cancer control in the 21st century
The American Cancer Society is outlining its vision for cancer control in the decades ahead in a series of articles that forms the basis of a national cancer control plan.
Oncotarget: Cancer pioneer employs physics to approach cancer in last research article
In the cover article of Tuesday's issue of Oncotarget, James Frost, MD, PhD, Kenneth Pienta, MD, and the late Donald Coffey, Ph.D., use a theory of physical and biophysical symmetry to derive a new conceptualization of cancer.
Health indicators for newborns of breast cancer survivors may vary by cancer type
In a study published in the International Journal of Cancer, researchers from the UNC Lineberger Comprehensive Cancer Center analyzed health indicators for children born to young breast cancer survivors in North Carolina.
Few women with history of breast cancer and ovarian cancer take a recommended genetic test
More than 80 percent of women living with a history of breast or ovarian cancer at high-risk of having a gene mutation have never taken the test that can detect it.
Radiotherapy for invasive breast cancer increases the risk of second primary lung cancer
East Asian female breast cancer patients receiving radiotherapy have a higher risk of developing second primary lung cancer.
More Cancer News and Cancer Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

Risk
Why do we revere risk-takers, even when their actions terrify us? Why are some better at taking risks than others? This hour, TED speakers explore the alluring, dangerous, and calculated sides of risk. Guests include professional rock climber Alex Honnold, economist Mariana Mazzucato, psychology researcher Kashfia Rahman, structural engineer and bridge designer Ian Firth, and risk intelligence expert Dylan Evans.
Now Playing: Science for the People

#540 Specialize? Or Generalize?
Ever been called a "jack of all trades, master of none"? The world loves to elevate specialists, people who drill deep into a single topic. Those people are great. But there's a place for generalists too, argues David Epstein. Jacks of all trades are often more successful than specialists. And he's got science to back it up. We talk with Epstein about his latest book, "Range: Why Generalists Triumph in a Specialized World".
Now Playing: Radiolab

Dolly Parton's America: Neon Moss
Today on Radiolab, we're bringing you the fourth episode of Jad's special series, Dolly Parton's America. In this episode, Jad goes back up the mountain to visit Dolly's actual Tennessee mountain home, where she tells stories about her first trips out of the holler. Back on the mountaintop, standing under the rain by the Little Pigeon River, the trip triggers memories of Jad's first visit to his father's childhood home, and opens the gateway to dizzying stories of music and migration. Support Radiolab today at Radiolab.org/donate.