More than a sweet treat: ‘lollipops’ could help diagnose mouth cancer

This article was originally posted in March 2024. It was updated in October 2024 to reflect the new Stand Up To Cancer funding. 

Today, diagnosing mouth cancer usually involves scalpels, stitches and anaesthetic. Stand Up To Cancer (SU2C) is funding a project that could replace it all with ‘lollipops’.

With £350,000 from SU2C and the Engineering and Physical Sciences Research Council, Dr Ruchi Gupta and her team at the University of Birmingham are working to turn their special hydrogel into a (flavoured) test that can quickly pick up signs of mouth cancer from saliva.

If it works, the lollipop could be a much less invasive alternative to biopsies, which involve cutting out small pieces of tissue to send for testing. It could also help doctors diagnose oral cancers earlier, when treatment is more likely to be successful.

How will it work? 

By mixing precise measures of water and a permeable polymer, Gupta’s team have developed a smart hydrogel capable of isolating tiny proteins from liquid samples. It’s like a fishing net – for fish tens of thousands of times smaller than the width of a human hair.  

That net is useful because, as they grow, mouth cancers release proteins that aren’t found in normal mouth cells. A test that catches them could make it possible to detect oral cancer when it first starts growing. It could even be used as a screening tool for people with a high risk of the disease.  

“Smart hydrogels have really exciting potential for diagnosing mouth cancer,” says Dr Gupta. “They can be easily moulded into shapes as a solid to ‘catch’ proteins in saliva.”  

And that’s not even the smartest part. To see if the proteins captured by the lollipop point to cancer, scientists need to be able to extract them from the hydrogel. They can do that by exposing it to a certain colour of light, which prompts it to release the captured proteins for testing. 

The next step

So far, lab tests have shown that the hydrogel can pick up proteins from artificial samples, but it takes a long time – currently up to 12 hours.    

It goes without saying that, sweet as it might taste, a 12-hour test isn’t suitable for patients. The new funding will mean Gupta and her team can focus on reducing the hydrogel’s capture time. In the clinic, the test will ideally take no more than 10 minutes.   

After speeding up the capture process, the team will start testing the gel with even more complex samples. There are a lot of proteins in saliva, and a diagnostic lollipop needs to be able to accurately pick up the ones associated with mouth cancers. 

Adding to the toolkit

Although this particular idea is the first of its kind for mouth cancer, you might have heard of a similar early detection tool for oesophageal cancer: the capsule sponge.

Like cancers in hard-to-reach parts of the mouth, oesophageal cancer is currently diagnosed with an endoscope, a flexible tube with a camera on the end. Doctors usually thread the endoscope through your nose to look for signs of oral cancer, but, for oesophageal cancer, it has to go through your mouth, down your throat and into your food pipe. Then it usually needs to take a biopsy, too.

Testing with the capsule sponge is a much simpler, cheaper and more comfortable procedure. It’s a small, coated pill on a thread with a sponge packed tightly inside, and you can swallow it like you would any other pill. When it reaches the stomach, the pill’s coating dissolves and the sponge starts to expand. Then, as it’s pulled back up with the string, the sponge collects cells from the oesophagus. After that, it can be sent off for analysis in the lab.

Cancer Research UK has been funding trials of the capsule sponge since it was first developed by Dr Rebecca Fitzgerald at the University of Cambridge. The ongoing BEST4 trial is testing it as a tool for monitoring people with a condition called Barrett’s oesophagus for signs of oesophageal cancer. Dr Gupta thinks the lollipops could be used in a similar way for oral cancers.

“In the first instance, it would likely be more appropriate to use this tool to screen individuals that are at high risk,” she says.

“So, for example, people who smoke a lot, because a high proportion of people who smoke develop oral cancer. And then maybe in the longer term, as we get more accurate biomarkers, it could be rolled out for mass production.”

The future of early detection

The £350,000 of funding from SU2C and the Engineering and Physical Sciences Research Council will support the next three years of work on Dr Gupta’s hydrogel. Beyond that, her team could also explore using it to help diagnose other types of cancer that produce protein-based biomarkers – potentially as a urine test. But these developments are likely to be a way off yet. 

“In the first three years, the aim is to show that the gel works well, with real samples in the lab,” says Dr Gupta.  

“Maybe after that, the gels could be tested in animal models to make sure there aren’t any side effects we need to know about, but that’s a little beyond the scope of our current work.” 

“We’re really excited to start the next phase of this project. We’re hoping that we can be the first to make a device which is much kinder for diagnosing mouth cancer for patients and easier for GPs to use.”

Until then, doctors probably won’t be recommending too many lollipops. Sometimes, though, we all deserve something sweet.