Colorectal cancer makes up 10% of all cancer deaths globally, and New Zealand — the southern region in particular — has very high rates of bowel cancer.
Research lead author and biochemistry PhD candidate Holly Pinkney said clinical developments were a priority for the disease, and their latest research may have identified new RNA molecules which would help doctors predict if a patient’s bowel cancer would return or not.
She said the Otago-led study could enable health professionals to separate colorectal cancer patients, who present at an early stage, into groups of "who will and who won’t" go on to develop metastasis and disease recurrence.
This would result in better treatment outcomes because high-risk patients would receive additional chemotherapy, while those who were at low risk would avoid over-treatment.
"We currently don’t have a good prognostic marker to help clinicians decide whether a patient with early-stage disease needs to only have their tumour removed, or if they need additional chemotherapy as well if, for example, the cancer is particularly aggressive and likely to cause relapse later in life."
She said while most research on therapeutic targets and biomarkers had focused on proteins, non-coding RNAs such as long non-coding RNAs (lncRNAs) comprised most of the transcriptome, and demonstrated superior tissue- and cancer-specific expression.
The researchers’ analysis identified 301 lncRNAs linked to malignant colorectal cancer regions, which were validated by using public data from the Dunedin Colorectal Cancer Cohort.
"Further validation using RNA–FISH revealed three lncRNAs that are detectable in stage two tumours, but not in normal epithelium, and are upregulated in metastatic tissues."
Ms Pinkney said high levels of these lncRNAs were associated with worse outcomes for patients, meaning they had the potential to be predictors of patient prognosis.
"We used some exciting technologies to do this research, including spatial transcriptomics — using a picture of the tumour like a map, to see exactly where genes are turned off or on — and AI, to help us predict what types of cells are present in the tumours.
"The development of new technologies, such as the spatial mapping of tumours or AI to make predictions about different parts of the tumour, are important for helping us do this research, and highlight how new scientific developments can be harnessed for cancer research," Ms Pinkney said.
