Ras Protein (IMAGE) University of Helsinki Caption How Ras protein signaling hijacks hepsin to turn a non-invasive tumor into invasive cancer. Credit Shishir Pant, Rita Turpin Usage Restrictions Credit: Shishir Pant, Rita Turpin 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.