Cancer Cell Line Inhibition by Osmotic Pump-administered Xylitol in a Syngeneic Mouse Model.

Background: This study aimed to evaluate the effects of continuous administration of xylitol (a commonly used dental prebiotic) via a subcutaneous osmotic minipump in a B16F10 syngeneic mouse model. Methods: The B16F10 syngeneic model consisted of 6-8-week-old C57BL/6 male mice subcutaneously injected with five × 10 5 B16F10 cells suspended in 100 μl PBS in the right flank. The mice were randomly assigned to two groups: Group 1 was the treatment group with 10% xylitol-loaded pumps (n=10), while Group 2 was the control group with saline-loaded pumps (n=10). Alzet minipumps were implanted subcutaneously in the left flank of B16F10-injected mice once more than 50% of all mice developed palpable tumors. After pump implantation surgery, the mice were monitored daily and weighed 2-3x/week. Tumor sizes were measured with calipers 2-3x/week, and all mice were euthanized when their tumors became too large (20 mm on any axis or 2,000 mm 3 ). The excised tumors were weighed and cut in half, with one half sent for histology and the other for metabolomic analysis. Results: The xylitol-treated group survived substantially longer than the control group. The tumor size was reduced by approximately 35% by volume. Histological sections of xylitol treat mice suggested reduced infiltration and angiogenesis, which is consistent with previous studies. The metabolomic analysis demonstrates that xylitol reduces the tumor production of histamine, NADP+, ATP, and glutathione from the tumor, thereby improving the host immune response with ROS reactive oxygen species. Conclusions: The results of this study suggest that xylitol has potential as an adjunct to oncological treatment and is being further investigated in comparison to monoclonal antibody therapy (Opdualag).