Nanoimiquimod for oral cancer prevention.

This study evaluated the efficacy of chitosan hydrogel with nanoencapsulated imiquimod 0.05% as a chemopreventive agent in an oral carcinogenesis model. Forty male rats were randomly assigned to four groups. Control (no treatment; n = 10); Hg (treatment with chitosan hydrogel; n = 10); Hgimq (treatment with hydrogel containing non-encapsulated imiquimod 0.05%; n = 10); HgNCimq (treatment with hydrogel developed with polymeric nanocapsules containing imiquimod at a concentration of 0.05%; n = 10). Carcinogenesis induction was performed using a 7,12-dimethylbenz[a]anthracene solution at a concentration of 0.5%. The treatment with the hydrogels was performed according to the groups. Compared with free imiquimod (Hgimq), nanoencapsulated imiquimod (HgNCimq) demonstrated superior chemopreventive efficacy. In the oral mucosa, HgNCimq completely prevented squamous cell carcinoma development and increased the proportion of animals without histopathological alterations (35% vs. 15%), while reducing epithelial dysplasia (5% vs. 50%) (p = 0.00). In the perioral skin, HgNCimq preserved normal histology in 80% of the animals compared with 55% in the Hgimq group (p = 0.03), supporting the enhanced therapeutic performance achieved through nanoencapsulation. In conclusion, this study demonstrated the promising potential of employing a nanotechnological hydrogel in preventing oral carcinogenesis.