2025 Early Detection Grant - Dr. Orion Tong

To defeat cancer, one of our best bets is to detect tumours early. Across nearly all  cancers, finding and treating early-stage disease gives you a much better chance of  cancer-free survival.  

But for cancers like pancreatic cancer, this is difficult because there aren’t many  clinical symptoms of early disease and its location deep in the body makes it hard to  monitor. 

We’re now getting to the point where we can pick up copies of DNA in the blood  released by cancer cells and detect them by gene sequencing. These ‘liquid biopsies’,  where a routine blood draw can be used to diagnose cancer coming back after surgery,  offer a huge window for better cancer monitoring. But we’ve only been exploring a small fraction of information present in this DNA, which limits how sensitive these tests are  and whether they’re suitable for detecting new pancreatic cancer. 

What this project aims to do, is expand the layers of cancer-specific information we can  get from tumour DNA in a blood draw. New gene sequencing methods allow us to  capture up to 7 distinguishing factors that can tag something as tumour DNA. In  particular, chemical modifications in DNA called ‘methylation’ are present on nearly  20% of DNA bases and shown to be involved in how cells turn into cancers. It’s starting  to become possible to use methylation in blood DNA to detect diseases like liver  damage during organ transplants. 

Via advanced new gene sequencing methods, we will analyse blood DNA from patients  with early-stage pancreatic cancer and compare their results to healthy individuals.  From this, we can develop new predictive DNA sequences for pancreatic cancer  detection. Using these sequences, it’s possible to design a highly targeted test that is  both sensitive enough to detect early stages of hidden tumours like pancreatic cancer  but with a reduced cost for implementation across clinics.  

Ultimately we are testing whether unlocking the full breadth of DNA analysis can  advance cancer detection to the point where a simple blood draw is sufficient to check  whether someone has an undetected tumour in their pancreas, and quickly move them  into surgery and therapy to save lives.