Study on the preventive effects of Pentoxifylline on 7, 12-Dimethylbez(a)anthracene and croton oil induced skin tumorigenesis in the female Swiss mouse.

Abstract

Intrduction: Cancer incidence is one of the human problems and in order to understand its mechanistic aspects several studies have been performed. Objective: In this study, we showed that pentoxyphyline has essential role in mice skin carcinogenesis.Methods & Materials: Eighty female Albino Swiss mice were divided into 4 groups and the back of the mice were shaved with Moser set and hair remover cream. After 24 hours, the animals of groups 2, 3, 4 were given 3 doses of 20, 40 and 80mg of pentoxyphyline/kg/mouse/twice a day/ intraperitoneally for 45 days .As a pretreatment study, pentoxyphyline was injeceted before using Dimethylbenz (a) anthracene (DMBA). Twenty-four hours after application of final dose, the mice of all groups were initiated by a single dose of DMBA (60g/100l acetone/mouse). After 7 days, animals were promoted topically by croton oil (1mg/200l acetone/mouse) twice weekly for period of 32 weeks. Results: At the end of 9th week the first tumors were observed in the groups of animals receiving pentoxyphyline 20… and 40 and control groups.However,. Also both in number and percentage of tumor incidence significantly were lower in groups receiving pentoxyphyline (80 µg) at various intervals of times. Discussion: The groups receiving 80 doses of pentoxifylline compared to the groups receiving 20 and 40 doses of pentoxifylline and the control group had higher tumor inhibition ability. It seems that inhibition of tumor incidence in mouse skin is probably due to the effect of pentoxifylline in preventing the production of cytokines and TNF-α protein. In general, the inhibitory mechanism of different doses of pentoxifylline in skin carcinogenesis not completely clear and needs further experimentations.