Commensal Bacteria Fight Colorectal Cancer

What are Commensal Bacteria? Commensal Bacteria are microorganisms that live in a symbiotic relationship with their host organism, such as ...

What are Commensal Bacteria? Commensal Bacteria are microorganisms that live in a symbiotic relationship with their host organism, such as humans, without causing harm. These bacteria can be found on the skin, in the digestive tract, and in other areas of the body.

Commensal bacteria play an important role in the body's immune system, helping to prevent the growth of harmful bacteria and promoting the overall health of the body. They can also help to break down food, produce vitamins, and regulate the immune system.

While commensal bacteria are generally considered beneficial, some can become harmful under certain conditions, such as when the immune system is weakened or if they enter parts of the body where they shouldn't be, such as the bloodstream or urinary tract. In such cases, they can cause infections and other health problems to the person.

Colorectal cancer is the third most commonly diagnosed cancer in the world. It is a complex disease that arises from a combination of genetic, environmental, and lifestyle factors. Despite advances in cancer research and treatment, the incidence and mortality rates of colorectal cancer remain high. However, recent studies have shown that commensal bacteria, the bacteria that live in our gut, may play a critical role in preventing colorectal cancer.

The human gut is home to trillions of microorganisms, including bacteria, viruses, fungi, and other microbes. These microorganisms play an essential role in maintaining our overall health by regulating digestion, metabolism, and immune system function. However, an imbalance in the gut microbiome, known as dysbiosis, can lead to various diseases, including colorectal cancer.

Several studies have shown that certain commensal bacteria can prevent the development of colorectal cancer. For example, a study conducted by researchers at the University of California, Los Angeles (UCLA), found that a strain of commensal bacteria called Bacteroides fragilis can reduce the incidence of colorectal cancer in mice.

The researchers discovered that B. fragilis produces a toxin called BFT (B. fragilis toxin), which activates the immune system and promotes the production of a type of immune cell called regulatory T cells. These cells play a crucial role in preventing inflammation and suppressing the growth of cancer cells. The researchers found that mice that were treated with B. fragilis had significantly lower levels of inflammation and fewer colon tumors than untreated mice.

Another study conducted by researchers at the University of Chicago found that a strain of commensal bacteria called Fusobacterium nucleatum plays a critical role in the development of colorectal cancer. The researchers found that F. nucleatum can attach to colon cells and promote the growth of cancer cells by suppressing the immune system's response. However, the researchers also found that certain strains of commensal bacteria can prevent the growth of F. nucleatum and reduce the risk of colorectal cancer.

These studies demonstrate the critical role that commensal bacteria play in preventing the development of colorectal cancer. However, more research is needed to understand how these bacteria work and how they can be used to develop new treatments for colorectal cancer.

In conclusion, commensal bacteria play a critical role in preventing the development of colorectal cancer. By understanding how these bacteria work and how they interact with the immune system, researchers may be able to develop new treatments for this complex disease. 

As we continue to learn more about the gut microbiome, it is clear that our health is intimately connected to the microorganisms that live inside us. By nurturing a healthy gut microbiome, we may be able to prevent and treat a range of diseases, including colorectal cancer.

Here are some reference links related to commensal bacteria:

1. Ley, R. E. (2010). Obesity and the human microbiome. Current opinion in gastroenterology, 26(1), 5-11. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3325238/
2. Belkaid, Y., & Hand, T. W. (2014). Role of the microbiota in immunity and inflammation. Cell, 157(1), 121-141. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4265395/
3. Honda, K., & Littman, D. R. (2016). The microbiota in adaptive immune homeostasis and disease. Nature, 535(7610), 75-84. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5102284/
4. Sender, R., Fuchs, S., & Milo, R. (2016). Revised estimates for the number of human and bacteria cells in the body. PLoS biology, 14(8), e1002533. https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.1002533
5. Human Microbiome Project. (n.d.). https://hmpdacc.org/