A recent study investigated tongue microbial populations as a potential tool for the early detection of pancreatic cancer.
Pancreatic cancer is among the deadliest cancer types. This disease causes hundreds of thousands of deaths every year, ranking seventh for the number of fatalities from cancer. Pancreatic cancer occurs more often in developed countries than in other areas of the world and the majority of cases happen in people over the age of 55 years.
The causes of this condition are not well known, but research has uncovered some of the risk factors. Smoking, family history and genetics, drinking alcohol, and diabetes are all risk factors for pancreatic cancer. Routine screening techniques for early detection are not available and risk reduction is currently the best way to prevent this disease. Risk reduction includes quitting smoking, a healthy weight, a diet rich in fruit and vegetables, regular exercise and health checks.
There are no recommended screening tests for pancreatic cancer
Pancreatic cancer at the early stages usually does not cause symptoms. Consequently, the disease is already at an advanced stage once patients seek medical help. Diagnosis at an advanced stage often means that surgery to remove the tumor is not an option, and even when it is, long-term survival is poor. For these reasons, research is focusing on discovering features of this cancer that would allow early diagnosis.
The human body naturally hosts populations of microbes that provide us benefits such as the production of precious nutrients. These microbes are known as the microbiota. Research studies demonstrated that variations in the microbiota composition could associate with cancer. This notion paved the way for more studies aiming at using the microbiota composition as a tool for cancer detection.
A recent study compared the tongue microbiota of pancreatic cancer patients with that of healthy individuals. This research approach hoped to find clues that could help diagnosing this condition at the early stages. Their results were published in the Journal of Oral Microbiology.
Tongue microbiota of pancreatic cancer patients differed from that of healthy individuals
The scientists collected samples from the tongue of 30 patients with stage I pancreatic cancer and 25 healthy individuals. All the participants were between the age of 45 and 65 years, had no oral health issues or other existing conditions and had not taken drugs during the three months prior to the study. The researchers used the samples collected from the participants to extract DNA from the bacteria living on the tongue. The DNA was analyzed to identify microbial species in each sample and make a comparison between healthy and ill people.
The results of this approach showed low levels of microbial types Haemophilus and Porphyromonas in samples from pancreatic cancer patients, while Leptotrichia and Fusobacterium were more abundant than in samples from healthy people. Microbial species living in our body associate with certain responses from the immune system. With this notion in mind, the authors suggest that alterations of the microbiota might be the origin of inflammatory processes that could lead to pancreatic cancer.
Analysis of tongue microbiota could be developed into methods to identify individuals at high-risk for pancreatic cancer
In conclusion, this study analyzed the tongue microbiota of patients with pancreatic cancer and compared it with healthy controls. The researchers found differences in the abundance of four types of bacteria. Differences in microbiota composition could be used in future approaches to developing tools to identify individuals at high-risk for pancreatic cancer. While this study provided novel insights on a link between microbiota and cancer, further studies in larger groups of people are necessary to confirm these results and prove the hypothesis proposed by the authors.
Written by Raffaele Camasta, PhD
- Ilic, M., & Ilic, I. (2016). Epidemiology of pancreatic cancer. World Journal of Gastroenterology, 22(44), 9694-9705.
- Lu, H., Ren, Z., Li, A., Li, J., Xu, S., Zhang, H., Jiang, J., Yang, J., Luo, Q., Zhou, K., Zheng, S., & Li, L. (2019). Tongue coating microbiome data distinguish patients with pancreatic head cancer from healthy controls. Journal of Oral Microbiology, 11(1).
- Tongue microbiome could help identify patients with early-stage pancreatic cancer. https://www.eurekalert.org/pub_releases/2019-01/tfg-tmc012519.php.