Using transgenic mice with regulated expression of potent oncogenes, Katrina Podsypanina developed experimental models that reproduce both tumour development and tumour regression in response to therapy and thus mimic the systemic disease and therapy resistance that is seen in human patients.

She found that some morphologically normal mammary cells are able to establish metastases and can cause tumour relapse. These findings may explain some long-standing puzzles, such as tumour dormancy and metastatic inefficiency in experimental models, and could redefine our approaches to cancer treatment. The goal of the Breast Cancer Biology research unit is to find solutions to interfere with the ability of breast cancer cells to form metastases and to establish a minimal residual disease responsible for tumour reoccurrence.