Objective: To evaluate the effect of gynostemma pentaphyllum mak (GP) on carcinomatous conversions of leukoplasia of the golden hamster cheek pouch induced by dimethylbenzanthracene (DMBA).
Methods: 284 golden hamsters, ranging from 4 to 8 weeks of age, 80 to 100 grams in weight were randomly divided into three groups: control, model and experimental groups. Control group (8 hamsters) were sacrificed at week 0 and week 12 for control. Model group (123 hamsters) were pasted in bilateral cheek pouches with 0.5% DMBA, 3 times a week for establishment of experimental leukoplasia, and sacrificed at week 2 to week 9 (12-22 hamsters were sacrificed a week). Experimental group (153 hamsters) were divided into three subgroups. Subgroup A underwent simultaneous DMBA pasting and oral taking of GP, and were sacrificed at week 6 and week 9. Subgroup B underwent oral taking of GP for 12 weeks after completion of DMBA pasting. Subgroup C underwent DMBA pasting after completion of oral taking of GP for 12 weeks.
Results: The earliest epithelial dysplasia and carcinoma in situ occurred at week 3 and week 6 after DMBA pasting. There were significant differences between subgroup B and model group for 3 weeks' administration of DMBA (P < 0.05), and between subgroup C and model group (P < 0.01), while there was no difference between subgroup B and model group for 6 week's administration of DMBA (P > 0.05).
Conclusions: GP could inhibit and reverse the carcinomatous conversions of leukoplasia of golden hamster cheek pouches, indicating its positive anticarcinogenic effect.