13 June 2012
Vol 4, Issue 138

About The Cover

Cover image expansion

ONLINE COVER Traveling Incognito. Shown embedded within normal liver tissue (orange) is a nest of metastasized colorectal cancer cells (pink). Oncolytic viruses (OVs; yellow) that adhere to white blood cells (WBCs; blue) in the host circulation acquire a stealth phenotype: They are protected from binding to neutralizing antibodies (white) in the host circulation and ride unharmed through the bloodstream. The WBC chaperones enter liver tissue by squeezing between vascular endothelial cells (shown lining the blood vessel). Once inside, the OVs infect and kill cancer cells while leaving normal liver cells unharmed. In this issue, Adair and colleagues show in cancer patients that a cell-associated oncolytic reovirus traveled through a patient's circulatory system, avoided antibody neutralization, and was deposited in metastatic tumor sites in the patient's liver. See also the accompanying Focus by Bell, who discusses how this important proof-of-concept information was not predicted from mouse tumor models. [CREDIT: B. STRAUCH/SCIENCE TRANSLATIONAL MEDICINE]