Qld researchers identify five distinct types of bowel cancer, raising hopes for better therapies

Queensland researchers have identified five distinct types of bowel cancer that are closely related to a patient’s age, in a breakthrough that could lead to more targeted treatments.

QUEENSLAND researchers have identified five distinct types of bowel cancer that are closely related to a patient’s age, in a breakthrough they hope will lead to more targeted treatments.

The three-year study by QIMR Berghofer Medical Research Institute scientists analysed more than 500 bowel cancer samples, including 216 from patients at the Royal Brisbane and Women’s Hospital.

The patients ranged in age from 25 to 85, with the scientists discovering that different genetic changes associated with bowel cancer happened at different ages.

Molecular biologist Lochlan Fennell, who conducted the study as part of his PhD, said the hope was that with more research into the five types of bowel cancer identified, better therapies could be tailored towards individual patients.

“Instead of treating every patient with the same drugs and assuming that every patient has the same prognosis, these subtypes might actually inform which drugs that we treat the patients with in future, and also their outcomes,” Mr Fennell said.

QIMR Berghofer Medical Research Institute molecular biologist Lochlan Fennell.

“The idea would be, and this is the idea with all cancers, to personalise our approach so that instead of providing one agent to everyone, we provide the right drug to the right patient at the right time.”

The study’s lead author Vicki Whitehall said the new way of classifying bowel cancer was based on DNA methylation within a patient’s tumour — or put simply, how genes were turned on and off.

“Our study found those changes in methylation of bowel cancers closely track with a patient’s age,” Associate Professor Whitehall said.

“This may indicate that bowel cancers occurring in younger and older patients may have different underlying causes. DNA methylation is a way a cell can turn its own genes on or off, but in cancer, this process gets hijacked and it turns on genes that favour growth and turns off genes that are meant to suppress it.

“This study suggests we should now focus on how methylation — the switching on or off of genes — causes these five different subtypes of bowel cancer and look for treatments that reduce DNA methylation to reduce the cancer risk.”

QIMR Berghofer Medical Research Institute's Associate Professor Vicki Whitehall.

About 17,000 Australians are diagnosed with bowel cancer annually and more than 4000 die from it each year.

The QIMR Berghofer study is published in the journal Cellular and Molecular Gastroenterology and Hepatology.

It was funded by the US National Institutes of Health, Pathology Queensland and Australia’s National Health and Medical Research Council.