Bioengineered Chewing Gum Shows Promise Against Cancer-Linked Oral Microbes in Head and Neck Cancer Patients
Key Insights
University of Pennsylvania researchers developed a bioengineered chewing gum containing plant-based compounds that reduced HPV levels by 93% in saliva samples from head and neck cancer patients.
The gum combines FRIL (search) protein and protegrin-1 (search) peptide to achieve over 99% reduction in cancer-associated bacteria Porphyromonas gingivalis and Fusobacterium nucleatum.
Unlike radiation therapy, the treatment selectively targets harmful microbes while preserving beneficial oral bacteria, offering potential as a low-cost adjunct therapy.
University of Pennsylvania researchers have developed a bioengineered chewing gum that dramatically reduces cancer-linked microbes in oral samples from head and neck cancer patients, offering a potential new approach to managing pathogens associated with tumor development and poor survival outcomes.
The study, led by Henry Daniell of the UPenn School of Dental Medicine, tested extracts from a chewing gum made with lablab bean powder against oral samples from patients with head and neck squamous cell carcinoma (HNSCC). The gum carries two active ingredients: FRIL (search), a naturally antiviral protein, and protegrin-1 (search), an antimicrobial peptide.
Targeting Key Cancer-Associated Pathogens
Head and neck squamous cell carcinoma, which forms in the lining of the mouth and throat, has been linked to elevated levels of human papilloma virus (HPV) and bacteria including Porphyromonas gingivalis and Fusobacterium nucleatum. These microbes are associated with cancer-promoting inflammation, invasion, metastasis and immune evasion.
"The global increase in oropharyngeal cancer is linked to HPV infection," Daniell said. "And Pg and Fn infections worsen survival rates of untreated recurrent or metastatic oral cancer, even after surgery and risk-adjusted adjuvant, or supplemental, therapies."
The researchers found that cancer samples carried much heavier bacterial loads than non-cancer controls, with counts 100 to 1,000 times higher in some cases. HPV was detected in all 14 saliva samples from HNSCC patients tested at one site, with viral levels far higher than in the non-cancer group.
Dramatic Microbial Reductions
In the ex vivo study, bean gum extracts reduced HPV levels by approximately 93% in saliva samples and 80% in oral rinse samples. In some cases, the gum aggregated all detectable HPV in the sample.
The bacterial results proved even more striking. While bean gum alone had limited antibacterial power, the addition of protegrin-1 (search) transformed its effectiveness. The combination reduced P. gingivalis by 4 to 6 logs (99.97% to 100%) and produced similar reductions for F. nucleatum. The treatment achieved these results after a single one-hour exposure.
Selective Antimicrobial Action
One notable aspect of the treatment was its selectivity. The gum-plus-protegrin combination had minimal effect on many nonpathogenic oral bacteria. Streptococci species, for example, were only partly reduced or not substantially reduced, likely protected by capsules or biofilms.
This selective effect contrasts with radiation therapy, which researchers noted can reduce beneficial oral bacteria while increasing disease-causing yeast such as Candida albicans. The narrower microbial targeting could offer advantages over approaches that disrupt the oral microbiome more broadly.
Clinical Implications and Future Directions
The study represents an ex vivo proof-of-concept rather than a clinical treatment trial. Researchers worked with saliva and oral rinse samples collected from patients, not testing the gum in patients over time. Important limitations include the lack of long-term monitoring of oral microbiome changes and testing of how well FRIL (search) and protegrin penetrate tumor cells in patients.
"Lip and oral cavity cancer was the seventh leading cancer type in cancer incidence and mortality rate worldwide in adolescents, young adults, and middle-aged adults in 2022," Daniell said. "Our findings support the value of advancing these therapies to clinical trials as adjuvants with current treatments or as prophylaxis to prevent infection and transmission."
The approach offers practical advantages, including affordability and ease of delivery. The lablab bean powder has already received Generally Recognized as Safe status, and the amount in each gum tablet falls far below quantities consumed in food-based toxicology testing. FRIL (search) in the gum remains stable for extended periods at room temperature.
If validated in clinical trials, the bioengineered chewing gum could provide a simple, low-cost method to reduce dangerous oral microbes without disrupting the entire microbial community, potentially serving as an adjunct to standard cancer care or as a preventive intervention for high-risk individuals.