A Clear Difference (IMAGE) Brown University Caption Dysregulation of the protein CHI3L1 allows melanoma (black specks) to spread to the lungs of mice. CHI3L1 was relatively unchecked in the lung on the right, compared to the lung on the left, which had much less spread of the cancer. Credit Elias lab/Brown University Usage Restrictions with credit 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.