Objectives: to examine the salivary microbiota of FA patients and their non-FA relatives.
Methods: Levels and proportions of 108 microbial taxa were determined in unstimulated whole saliva using checkerboard DNA- DNA hybridization. Prevalence of uncultivated/unrecognized was assessed using the human oral microbial identification microarray (HOMIM). Significant differences between groups were sought using the Mann-Whitney test.
Results: FA patients (n=18) were younger (mean age± SD; 18.9±9.8 years) than non-FA subjects (n=8) (32.1±19.8), but gender distribution was similar (61% and 62%females, respectively). FA patients presented higher microbial load (mean total DNA probe counts ± SD; 187.2 x10^5±97.8) than non-FA individuals (155.2 x10^5±93.7). The most numerous taxa were (FA vs. non-FA; mean counts x 10^5 ± SD) Neisseria mucosa (23.4±24.8 vs. 18.9±21.3), Veillonella dispar (14.0±10.0 vs. 10.2±6.4), Prevotella tannerae (12.1±7.5 vs. 10.5±5.6), Helicobacter pylori (9.8± 5.3 vs. 7.8±3.8) and Candida albicans (6.4±4.0 vs. 4.5±2.1). Porphyromonas endodontalis cell counts were higher in FA (3.5±1.5 vs. 0.9±0.6, p<0.05). Differences in mean %DNA probe count (± SD) were observed for P. endodontalis (2.4±2.2 vs. 0.5±0.3), Streptococcus sobrinus (2.3±0.6 x 1.8±0.5) and Enterobacter agglomerans (1.8±0.1 vs. 2.3±0.4) (p<0.05) (FA vs. non-FA, respectively). Among uncultivated/unrecognized taxa, Synergistetes sp. oral taxon (ot) 360 and Capnocytophaga sp. ot 335 were present in 100% of FA samples, Haemophilus sp. ot 036 in 35.7% and Prevotella sp ot 308 and 309 and Capnocytophaga sp ot 324 were present in 7.1%.
Conclusions: There were differences in the salivary microbiota between FA and non FA. These findings might provide insights into the role of microorganisms in oral cancer.
Keywords: Bacterial, Carcinogenesis, Host-microbial interactions, Microbiology and Saliva