Dentists are at the frontline of oral cancer detection and having the ability to suggest something as simple as a blood test could ultimately save lives. By Samantha Trenoweth.
Samantha Khoury is a bright, tenacious, idealistic young scientist based in the Centre for Health Technologies at University of Technology, Sydney (UTS). She is part of a groundbreaking team that is working to improve the prognosis for many of the thousands of Australians who are diagnosed with oral cancer annually. She is also an early riser. “I do my best work before lunch time,” she admits, sparkly eyed at 9am, “so I like to get in here as early as I can and begin testing while my mind is fresh and alert.” The team, led by Dr Nham Tran, has discovered blood biomarkers for the potential early diagnosis of oral cancer.
This research began eight years ago at Royal Prince Alfred Hospital and the University of Sydney, where Dr Tran was a post-doctoral investigator working on human papillomavirus (HPV) in oral cancers. His idea was to discover whether molecules known as small ribonucleic acids (RNAs) could be used as biomarkers for the early detection of oral cancers. “These small RNAs are tiny molecules—just 21 or 22 nucleotides long,” Dr Tran says. “And they regulate gene expression in all cells. When they break down, everything goes haywire.”
Oral cancer is the sixth most common form of cancer in the world but the amount of attention and medical research it attracts is disproportionately low. “Studies have been done, profiling the blood of patients with other major cancers, like lung cancer, breast cancer and colorectal cancer,” Dr Tran explains. “Oral cancer seems neglected.” Samantha Khoury and Dr Tran have successfully discovered a set of blood markers. Now her PhD studies involve validating hundreds of blood samples for these biomarkers. When their work is complete, the final outcome will be a diagnostic blood test for the early detection of oral cancer. This will be as simple and hopefully as affordable as the blood tests that doctors regularly request to check cholesterol, iron or blood sugar levels.
The discovery of these biomarkers in the blood will certainly save lives. It will mean that oral cancer can be detected far earlier, through a simple, non-invasive blood test rather than a painful biopsy. And this is crucial because, globally, the incidence of oral cancer is on the rise. “In India and parts of Asia,” Dr Tran explains, “rates are high as a result of the carcinogens that people ingest. It’s the combination of smoking and the betel nut that they chew. In India, younger people are diagnosed with oral cancer—often they’re in their early twenties—whereas, in Australia and the USA, the average age for diagnosis is 62.” “In Australia and other developed countries,” Khoury adds, “oral cancer has primarily been a disease of older men who have a history of tobacco and alcohol consumption.
As our populations age, we’re naturally seeing an increased incidence of this cancer. “We are also beginning to see oral cancers appear in different age groups. In recent years, doctors have identified more oral cancers in young women who have been exposed to the HPV. The HPV vaccine will help significantly, but there are still a lot of people around the world who haven’t received it. In Australia it was delivered free by the government but in America that didn’t happen so, for most people, it’s prohibitively expensive.” Khoury’s research has been motivated by a combination of personal and academic concerns. “My grandfather passed away from cancer the year that I entered honours,” she explains. “At that point, I knew that I wanted to practise preventative medicine, and science gives you that opportunity. To be able to discover new techniques and increase the scope of what a doctor can do—that’s a very exciting and powerful position to be in. For my PhD, I wanted to choose an innovative idea that could be translated into a clinical care setting. That could go into the community, into hospitals and benefit people.”
This innovation, currently being filed under a UTS provisional patent, is cost effective and convenient, and can feed into a whole range of Australian medical screening programs. When the current round of testing is complete, the team will publish its findings and seek approval from regulatory bodies in the United States and Australia. If successful, they hope to further engage with the dental profession to implement a national screening program for oral cancer.
“A dentist is often the first person to pick up changes associated with oral cancer when they do a visual inspection of the mouth,” Samantha explains. “Dentists are at the frontline of oral cancer detection and they will be reassured when they can suggest something as simple as a blood test if they notice changes in a patient’s mouth. Early intervention with head and neck cancer makes a very big difference making dentists aware of their role is an important strategy.” Approximately 1100 people are diagnosed with oral cancer annually, which equates to three Australians being diagnosed per day. Currently, the only two options available for patient diagnosis are the brush test and tissue biopsy. This research will provide the first ever blood-based diagnostic kit, which the team has tentatively named miLifeTM. Because the majority of oral cancers are found as late stage cancers, the death rate is high—around 43 per cent at five years from diagnosis.
However, if oral cancers are detected early, patients can have a 90 per cent survival rate. So this is a discovery with enormous potential to save lives. Khoury says she has her parents to thank for her swift scientific thinking. “They have been a big inspiration,” she smiles. “I try to model what I do in the laboratory, or in meetings, on the way they organise their own lives. Technical skills can be learnt, knowledge can be gained by reading but the biggest skill set that you can have is the ability to unlearn and relearn things—a bit of neuro-plasticity. If you’re flexible, then you can take anything in your stride. It’s important not to get stuck.” Her sister is a musician studying at Julliard in New York and Samantha is grateful that her parents encouraged both of them to seek out the things that they were good at and passionate about and then helped them to pursue those ambitions. “My parents wanted me to be open to new ideas, to be a good thinker and to make decisions for myself based on logic and reason. Science appealed to me because I am a logical person. I like science because it explains things. I was always wondering, always curious, always asking why, and science is a great way to channel that. I wanted to explore what makes things tick.” Dr Tran came to science through a more circuitous route (via information technology) but he too enjoys its logic and is motivated by a desire “to help make a better world”. “If we can help someone who comes in for a regular appointment at the dentist or the doctor,” he says, “and we can ensure their cancer is diagnosed early, then that will be an achievement. These biomarkers can change the diagnostic landscape and prognostic outcome for patients with oral cancer. “I think we are on the way to that,” he adds, “and hopefully, in the next couple of years, we might be able to provide some genuine help in the community. There are some challenges still in front of us but I think we are going to get there.”