PTEN Cancer Stem Cells (IMAGE) Michigan Medicine - University of Michigan Caption These are tumors generated from normal breast cells and from breast cells in which PTEN has been deleted. Credit University of Michigan Health System Usage Restrictions for use in conjunction with stories about this research License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.