Currently, the efficiency of the identification of novel therapeutics for cancer is pitifully low. In large part, this is due to the failure of current animal models to be predictive for the human disease. Yet animal models are essential to develop drugs against metastatic cancer. Thus, we need a better animal model, for cancer to fully exploit the rapid development of novel therapeutics and avoid a bottleneck in their development for use in humans. Current animal models are essentially limited to rodents, which differ genetically, biochemically, physiologically and anatomically from humans. Pigs, however, are very similar to humans in all these aspects by comparison. Indeed, the minimum genetic requirements for tumorigenic transformation in the pig appear to be almost identical to those required for humans. There is currently no transgenic pig model for human cancer. We are in the process of developing a transgenic "oncopig" model for breast cancer using breast specific induction of miRNA multimers in swine. This model could serve as a test bed for the development of novel breast cancer therapeutics and preventatives in a near-human system.