Metastatic Melanoma Tumors (image) Weizmann Institute of Science Share Print E-Mail Caption Metastatic melanoma tumors. Left exhibits low or absent expression of RASA2 and reduced survival, typical of about 35 percent of patients. The sample on the right exhibits high RASA2 expression and increased survival. Credit Weizmann Institute of Science Usage Restrictions None Share Print E-Mail 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.