A combination of green tea extract, specific nutrient mixture and quercetin: An effective intervention treatment for the regression of N-methyl-N-nitrosourea (MNU)-induced mammary tumors in Wistar rats.

Mammary tumors were developed by intraperitoneal injection of N-methyl-N-nitrosourea (MNU) in 21-day-old, sexually immature female Wistar rats. Injection of MNU was repeated 14 weeks after the first one. When palpable tumors were evident in all of the rats, various dietary treatments were initiated for a period of 8 weeks. The treatments were designed to provide 30 mg green tea extract either alone or as a nutrient mixture (E). E was then expanded to include either a nutrient supplement (N), quercetin (Q) or both (N+Q). At the end of the treatment, tumor size/rat measured in the live rats was significantly lower in the groups receiving E, E+Q, E+N and E+N+Q than in the positive control (PC) group which did not receive any dietary treatment. Tumor number/rat, tumor volume/rat and tumor weight/rat were evaluated after sacrificing the rats on the 60th day. The rats receiving E+N+Q showed significantly lower values for the three parameters as compared to the PC group. The PC group showed 24 carcinomas mostly of grade III severity, while the E+N+Q group had only 6 carcinomas, all of which were of grade II severity.