A specially designed chewing gum could one day become an unusual tool in the fight against some head and neck cancers.
Researchers at the University of Pennsylvania have developed a bean-based gum that can target a virus and harmful bacteria linked to cancers of the mouth and throat.
Early laboratory tests using samples from patients produced striking results.
Head and neck cancer is a broad term for cancers that develop in areas such as the mouth, throat and voice box.
One common type is head and neck squamous cell carcinoma, which begins in the thin, flat cells lining these areas.
Treatment can include surgery, radiation, chemotherapy and newer medicines, but advanced disease can still be difficult to control.
Researchers are increasingly interested in the microbes that live in the mouth because some may influence cancer risk or how a cancer behaves. The mouth normally contains a large community of bacteria, viruses and other microorganisms. Many are harmless or helpful, but certain microbes have been linked to disease.
One important example is human papillomavirus, better known as HPV. Some types of HPV can infect cells in the mouth and throat and are a major cause of cancers in the oropharynx, which includes the back of the throat and the tonsils. HPV-related throat cancers have risen in several countries in recent decades.
The researchers also focused on two bacteria called Porphyromonas gingivalis and Fusobacterium nucleatum. Both can live in the mouth and have been studied for their links to gum disease and cancer. Previous research has associated these bacteria with poorer outcomes in some people with oral cancer.
The new work was led by Henry Daniell at the University of Pennsylvania School of Dental Medicine. The findings were published in the peer-reviewed journal Scientific Reports. The team tested extracts from a bioengineered chewing gum using oral samples collected from people with head and neck cancer.
The gum builds on earlier work involving lablab beans. It contains a naturally occurring plant protein known as FRIL that can trap certain viruses. Instead of delivering a conventional drug through a pill or injection, the idea is to release useful proteins directly in the mouth while a person chews.
In tests with patient saliva, extracts from the bean gum reduced HPV levels by 93 percent. In oral rinse samples, HPV levels fell by about 80 percent. These results suggest that the material in the gum can capture or reduce large amounts of the virus under laboratory conditions.
The researchers then added another ingredient designed to attack harmful bacteria. This was protegrin, a small antimicrobial substance that can kill certain microbes. After one dose of the engineered gum extract, levels of P. gingivalis and F. nucleatum fell to almost zero in the tested samples.
A particularly interesting part of the result was what apparently did not happen. The treatment did not seem to wipe out the beneficial bacteria that normally share the mouth. Preserving these organisms could matter because a healthy oral microbial community helps maintain the normal environment of the mouth.
Cancer treatments can sometimes disturb that balance. Radiation directed at the head and neck, for example, can damage tissues and alter the organisms living in the mouth. Such changes may allow unwanted microbes, including the yeast Candida albicans, to grow more easily in some patients.
A gum that acts locally could therefore have several possible uses if future studies confirm that it is safe and effective. It might eventually be used alongside standard cancer treatment to reduce microbes associated with disease. Researchers also believe the approach could potentially help reduce infection or transmission in some settings.
The attraction of chewing gum as a delivery system is its simplicity. It does not require an injection, complicated equipment or a hospital procedure, and the active ingredients can come into direct contact with the mouth and throat. Plant-made proteins could also potentially make production less expensive than some conventional biological medicines.
However, the results should not be interpreted as evidence that chewing gum can currently treat or prevent cancer. The experiments tested gum extracts against microbes in patient samples rather than showing that people who chew the gum have better cancer outcomes. Reducing HPV or bacteria in a sample is very different from shrinking a tumor or improving survival.
It is also not yet clear how long the effects would last inside the human mouth, how often the gum would need to be used or what dose would be best. Researchers will need clinical trials in people to study safety, effectiveness and possible side effects. They will also need to learn whether lowering these microbes actually changes the course of cancer.
The study is nevertheless interesting because it combines two ideas that are gaining attention: targeting cancer-related microbes and delivering treatments directly where they are needed. The large reductions seen in HPV and the two bacterial species provide a strong reason to continue testing the approach. Preserving helpful oral bacteria at the same time could be an additional advantage.
Overall, the research offers an inventive early-stage strategy rather than a ready-made cancer therapy.
Its greatest strength is the clear laboratory effect against several microbes associated with head and neck cancer, while its greatest limitation is the lack of evidence yet from treatment trials in patients. If future clinical studies confirm the benefits, a simple piece of chewing gum could eventually become a useful partner to established cancer care.
If you care about cancer, please read studies that a low-carb diet could increase overall cancer risk, and berry that can prevent cancer, diabetes, and obesity.
For more health information, please see recent studies about how drinking milk affects the risks of heart disease and cancer and results showing vitamin D supplements could strongly reduce cancer death.
