Dr. Donna Albertson from the University of California San Francisco (left) and Dr. Brian Schmidt (New York University College of Dentistry) and their team looked at shifts in the composition of the oral microbiome, to potentially be promoters or causes of oral cancer. (Photo courtesy of NYCUD Buestone Center)

Jun 16, 2014 | News Americas

NEW YORK, USA: A recently published study has suggested that evaluating shifts in the composition of the oral microbiome could be a new method for monitoring oral cancer development, progression and recurrence. The researchers believe that changes in the microbiome could be used as biomarkers for oral cancers or precancers in the future.

In order to investigate changes in the oral microbiome associated with oral cancer, researchers at the New York University College of Dentistry in collaboration with researchers at the University of California, San Francisco, collected cancer samples and anatomically matched control samples from the oral cavity of patients and healthy individuals, respectively.

The researchers were able to distinguish most cancer samples from precancer and control samples by looking at differences in bacterial composition. They found that abundance of Firmicutes, particularly Streptococcus, and Actinobacteria, especially Rothia, was significantly decreased relative to control samples from the same patient for precancers. However, this was not observed in samples from the tongue and floor of the mouth from healthy individuals, indicating that shifts in the composition of the microbial community may occur early in oral cancer development.

Although larger-scale studies are needed to determine whether shifts in the oral microbiome are cancer promoting, the current findings suggest that such changes could be used to detect cancerous and precancerous lesions in noninvasively collected swab samples. In addition, the oral microbiome may provide signatures that can be used as biomarkers for monitoring field changes associated with the high rate of second and primary oral cancers and their recurrence.

According to the Centers for Disease Control and Prevention, more than 30,000 new cases of cancer of the oral cavity and pharynx are diagnosed each year. The agency estimates that over 8,000 deaths occur annually due to oral cancer.

The study, titled "Changes in Abundance of Oral Microbiota Associated with Oral Cancer," was published online on June 2 in the PLOS ONE journal.