RETARDATION OF EXPERIMENTAL TUMORIGENESIS AND REDUCTION IN DNA-ADDUCTS BY TURMERIC AND CURCUMIN

Turmeric and its active principle curcumin have been extensively inves tigated for their antimutagenic and antioxidant effects in bacterial a nd animal systems. Because oral cancers are common in India, an experi mental model of 7,12-dimethylbenzanthracene-induced buccal pouch tumor s in Syrian Golden hamsters was used to evaluate the tumor retardation effects of turmeric and curcumin. Turmeric and/or curcumin was admini stered in the diet and/or applied locally for 14 weeks along with 7,12 -dimethylbenzanthracene. After the experimental period, the animals we re sacrificed and oral pouches were examined for tumor number and size . DNA adducts were estimated by P-32 postlabel assay in the cheek pouc hes. Neoplastic changes were graded by histopathology. The results of the study suggest that turmeric or curcumin in the diet and/or applied locally significantly reduced DNA adducts at the target site. Tumor n umber and tumor burden were significantly lower (p < 0.05) in the anim als that received turmeric in the diet and applied locally. The histop athological examinations suggested that the neoplastic grading was lea st in the animals fed or painted with curcumin (p < 0.05). The current study demonstrates that turmeric or curcumin administered in the diet or applied as paint may have a plausible chemopreventive effect on or al precancerous lesions.