Tumor Cells Moving through Collagen (IMAGE) Drexel University Caption This is a microscopic image of a tumor cell migrating through collagen. Credit Photo by Ryan Petrie. Usage Restrictions Credit as specified. 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.