The effect of N-methyl-N-nitrosourea (MNU) and dimethylbenzanthracene (DMBA) in developing the mammary tumor in Wistar albino and Sprague dawley rats-A comparative study

The existing methods for the induction of tumor in mammary cancer research using animal models are lengthy, perilous, and sometimes irreproducible and not convenient. Therefore, objective of the study was to find out, a most effective less time consuming model to produce mammary tumor in animal mode. We used two different strains of animals and two carcinogens MNU and DMBA in different concentrations to induce mammary tumor. In this study we found that Sprague Dawley rats developed malignant mammary tumor within two months of time compared to the Wistar strain and size of the tumor increased exponentially. Histopathological examination revealed that the tumors which were induced were showing adenocarcinomas of mammary gland. Therefore, this study suggests that Sprague dawley rats and MNU as carcinogen is the better animal model for tumor induction having least tumor latency and maximum tumor incidence in breast cancer research compared to Wistar albino rats.