Link between gut bacteria and early onset colorectal cancer

Understanding the link between gut bacteria and the development of early onset colorectal cancer: Researchers at the University of Melbourne Centre for Cancer Research have received funding from Cancer Council New South Wales to better understand the non-genetic causes of early-onset colorectal cancer, presenting screening opportunities for the vulnerable group.

Associate Professor Dan Buchanan and his Colorectal Oncogenomics Group will explore how certain bacteria in a person’s bowel cause changes to their DNA and how this process leads to the development of cancer.

The study will inform cancer risk prediction and screening by identifying features that can help to predict which young people are likely to develop colorectal cancer caused by bacteria.

A group of early-onset colorectal cancer consumers – people with personal experience of cancer – informed the development of the study, highlighting issues to be explored such as not knowing what caused their cancer and the lack of understanding of familial risk.

Consumer and CI on the grant Natalie Diepenhorst said “I was diagnosed with stage 2 colorectal cancer at the age of 32; the third member in my family to be diagnosed spanning three generations. However, genetic testing shows no known heritable link for us.”

“This project will work towards identifying at-risk individuals beyond genetics and gives me hope for early diagnosis and prevention of colorectal cancer, particularly in people under 50.”

Associate Professor Buchanan said that by developing novel approaches to identify young adults in the population who have an elevated risk of early-onset colorectal cancer, they could be offered preventative screening.

“We know that altered gut bacteria causes an important subset of early onset colorectal cancer, but there is currently no way to detect this subset, or those individuals at higher risk of developing it.”

“This funding is enabling research that will provide an unprecedented opportunity to impact cancer control through targeted prevention in young adults, a group who are currently not offered routine screening,” he said.

Early-onset colorectal cancer has been increasing in incidence globally for over 20 years, with the cause of the increase unknown. In Australia, incidence has increased by 85-100 per cent for ages 20-29 and by 35 per cent for ages 30-39. This rise is projected to double by 2030.