Peptostreptococcus, Fusobacterium, Alloprevotella, and Capnocytophaga were more abundant, whereas Rothia and Haemophilus were less abundant

Analysis of oral microbiota in Japanese oral cancer patients using 16S rRNA sequencing Publication date: Available online 16 May 2019 Source: Journal of Oral Biosciences Author(s): Yasuharu Takahashi, Jonguk Park, Koji Hosomi, Tomonori Yamada, Ayaka Kobayashi, Yuji Yamaguchi, Susumu Iketani, Jun Kunisawa, Kenji Mizuguchi, Nobuko Maeda, Tomoko Ohshima Abstract Objectives It is important to determine the cause of increasing oral cancer occurrence and mortality rates in Japan, because the mortality rate has recently decreased in other developed countries. The impact of microbiota in carcinogenesis, especially in the digestive tract has been reported. This study aimed to clarify the relationship between oral cancer and oral microbiota in Japanese patients. Methods DNA was extracted from salivary samples of 60 oral cancer patients and 80 non-cancer individuals as controls. We performed metagenomic analysis using 16S rRNA amplicon sequencing. Statistical analysis in this study was performed using R (version 3.5.0). Results Oral cancer patients showed higher α-diversity compared to the control group, and the β-diversity between the two groups differed significantly. Further, there was a significant difference in the abundance ratio of bacterial genera between the two groups. Peptostreptococcus, Fusobacterium, Alloprevotella, and Capnocytophaga were more abundant in the cancer group compared to the control, whereas Rothia and Haemophilus were less abundant (p < 0.01). A negative correlation in the microbiota composition was confirmed between the operational taxonomic units (OTU) of genus Rothia and T-stage progression using the TNM classification method. We performed logistic regression analysis to investigate the impact factor for the oral cancer group, and the result showed that Chao 1 index and sex are statistically significant variables. Conclusions In this study, we observed an increased bacterial diversity in oral cancer patients and found distribution changes for some bacteria.