Aim: Cyclo-oxygenase-2 (COX2) plays a prominent role in carcinogenesis. This study addresses the effects of two nutraceutical compounds on the expression of COX2 and tumor-associated inflammation in human papillomavirus type 16 (HPV16)-transgenic mice. Materials and Methods: Six-week - old FVB/n mice were supplemented with rutin or curcumin for 24 weeks: HPV16(-/-) no treatment, n=12; HPV16(+/-) no treatment, n=13; HPV16(+/-) rutin, n=12; HPV16(+/-) curcumin, n=13. HPV16-induced skin lesions and their inflammatory infiltrates were studied histologically. COX2 expression was assessed immunohistochemically. Results: Rutin reduced COX2 expression in the dermis (immunostaining score 7.83 versus 11.25 in untreated HPV16-transgenic mice) and epidermis (4.5 versus 10.0). Curcumin led to dermal and epidermal scores of 10.5 and 4.5. Both compounds reduced leukocytic infiltration, but neither prevented epidermal dysplasia. Conclusion: COX2 expression in HPV16-induced lesions may be modulated by nutraceuticals, reducing tumor-associated inflammation. However, this was not sufficient to block carcinogenesis, calling for additional studies focused on combination therapies.
Cancer patients often show a wasting syndrome for which there are little therapeutic options. Dietary polyphenols have been proposed for treating this syndrome, but their usefulness in cases associated with human papillomavirus (HPV)-induced cancers is unknown. We characterized HPV16-transgenic mice as a model of cancer cachexia and tested the efficacy of long-term oral supplementation with polyphenols curcumin and rutin. Both compounds were orally administered to six weeks-old HPV16-transgenic mice showing characteristic multi-step skin carcinogenesis, for 24weeks. Skin lesions and blood, liver and spleen inflammatory changes were characterized histologically and hematologically. Hepatic oxidative stress, skeletal muscle mass and the levels of muscle pro-inflammatory transcription factor NF-κB were also assessed. Skin carcinogenesis was associated with progressive, severe, systemic inflammation (leukocytosis, hepatitis, splenitis), significant mortality and cachexia. Curcumin and rutin totally suppressed mortality while reducing white blood cells and the incidence of splenitis and hepatitis. Rutin prevented muscle wasting more effectively than curcumin. Preservation of muscle mass and reduced hepatic inflammation were associated with down-regulation of the NF-κB canonical pathway and with reduced oxidative stress, respectively. These results point out HPV16-transgenic mice as a useful model for studying the wasting syndrome associated with HPV-induced cancers. Dietary NF-κB inhibitors may be useful resources for treating this syndrome.