Mouse oral and fecal microbiomes in 4-NQO model

Sixty-four C57BL/6 mice sourced from Jackson Laboratory and Taconic Biosciences (n=32 per vendor) were treated with 4-NQO for 16 weeks to induce oral carcinogenesis. Mice were concurrently randomized to receive biweekly oral swabbing with either Streptococcus mitis or vehicle control, which continued for an additional 12 weeks. Species-level profiling of the oral and fecal microbiomes at baseline and at 8 weeks was performed using 16S rRNA gene sequencing. At week 32, mouse tongues were evaluated macroscopically and histologically for tumor development.