Specific oncolytic activity of herpesvirus saimiri in pancreatic cancer cells

The potential use of oncolytic viruses in the treatment of cancer has been investigated for some time. A variety of agents have been studied, includin g some which appear to be selectively replication-competent in cancer cell lines. In this study, we have investigated the ability of herpesvirus saimi ri to specifically lyse selected human cancer cell lines. Upon infection wi th a replication-competent virus carrying the EGFP reporter gene and a neom ycin resistance marker, the pancreatic cancer lines MIAPACA and PANC-1 exhi bited definite cytopathic effects, in contrast, the colonic carcinoma cell lines SW480 and HCT116 were phenotypically unaltered. in addition, stable c ell lines could not be generated from PANG-I infected cultures, in marked c ontrast to cultures of cells from other human tissues. Virus recovery assay s demonstrated that all of the cell lines produced a small amount of virus post-infection, but that virus replication was minimal after 1 week in cult ure. in addition, treatment with acyclovir inhibited Virus replication but paradoxically increased cytopathic effect. These data suggest that herpesvi rus saimiri may have potential as an oncolytic agent for the treatment of p ancreatic cancer. (C) 2000 Cancer Research Campaign.