Quercetin in Dimethyl Benzanthracene Induced Breast Cancer in Rats

Problem statement: Vincristine a commonly used anticancer agent in the treatment of breast cancer results in serious adverse effects like teratogenicity, neurotoxicity and carcinogenicity on long term use. Drug resistance is also a common problem encountered with vincristine. Hence the effect of flavonol quercetin, a known antioxidant with no known documented adverse effect was tried in treatment of DMBA induced breast cancer in female rats and its effect was compared with vincristine. Approach: Quercetin at the dose of 50, 100-200 mg kg^-1 body weight was administered in DMBA induced breast cancer in female wistar rats and its effects were compared with Vincristine. The anti oxidant enzymes, catalase, glutathione peroxidase and superoxide dismutase and Thiobarbituric Acid Reactive Substances (TBARS) level in cancerous breast tissue, TBARS and catalase in plasma and superoxide dismutase and glutathione peroxidase in erythrocyte lysate were estimated. Results: Quercetin supplementation at the dose of 100 mg kg^-1 body weight was most effective in alleviating cancer symptoms and was comparable to vincristine. The plasma TBARS were reduced and breast tissue TBARS were elevated. The antioxidant enzymes were rejuvenated by quercetin supplementation at all three dose levels. Conclusion: Quercetin is found to be an effective chemotherapeutic agent in the treatment of breast cancer on par with vincristine. Being a plant product, quercetin can also be used in chemoprophylaxis in high risk individuals with genetic predisposition towards breast cancer. Besides, it can be given orally and has a wide margin of safety.