Contribution of enterotoxigenic Bacteroides fragilis to colorectal carcinogenesis

Support this project
Status: In-progress
Year: 2016
Funded: $88,215
Grant Type: Major Project Grant

Colorectal cancer is a common type of cancer, and while recent evidence suggests that gut bacteria may increase risk, the exact mechanisms remain elusive. Bacterial infections can cause chronic inflammation, which has been linked to cancer development.

The Bacteroides fragilis toxin potentially alters intracellular signalling pathways that are also linked to cancer development. We will explore how chronic inflammation as a result of enterotoxigenic B. fragilis (ETBF) infection is associated with development of colorectal cancers, including whether genetic mutations arise as a result of this chronic inflammation.

We will also investigate the role of microRNAs as a potential mechanism that regulates this process. MicroRNAs are small RNA molecules that do not code for proteins, but have recently been shown to play important roles in many cellular processes, including the development of cancer. We hope that this project will identify novel markers for the early detection of colorectal cancer.

Researcher // Dr Rachel Purcell – University of Otago

Dr Purcell is a Research Fellow with the Department of Surgery. She has a background in molecular biology and cancer genetics. Her research is centred on the molecular mechanisms of pathogenic bacteria in colorectal carcinogenesis.

More About Dr Rachel Purcell

What is Colorectal Cancer?

Colorectal cancer (CRC), also known as bowel cancer and colon cancer, is the development of cancer from the colon or rectum (parts of the large intestine). A cancer is the abnormal growth of cells that have the ability to invade or spread to other parts of the body. Signs and symptoms may include blood in the stool, a change in bowel movements, weight loss, and feeling tired all the time. Most colorectal cancers are due to old age and lifestyle factors, with only a small number of cases due to underlying genetic disorders. Other risk factors include diet, obesity, smoking, and lack of physical activity. Dietary factors that increase the risk include red meat, processed meat, and alcohol. Another risk factor is inflammatory bowel disease, which includes Crohn’s disease and ulcerative colitis. Some of the inherited genetic disorders that can cause colorectal cancer include familial adenomatous polyposis and hereditary non-polyposis colon cancer; however, these represent less than 5% of cases. It typically starts as a benign tumor, often in the form of a polyp, which over time becomes cancerous.

People in New Zealand die of colorectal cancer each year.
0 nd
It is the second most commonly occurring cancer in women.
0 rd
It is the third most commonly occurring cancer in men.
0 m
Worldwide there were over 2 million new cases in 2018.

Stay in touch with CMRF

// Get all the latest news and insights to your inbox