Figure 8.

Clot formation results in reduced proliferation and increased apoptosis in oncolytic virus (OV)-treated tumors. BALB/c mice with CT-26 tumors were treated intravenously with either vesicular stomatitis virus (VSV) alone or with heparin in order to inhibit VSV-induced coagulation. Representative histological images are shown with corresponding quantification from four mice per group. Clot formation was quantified as described previously. The same tumors were stained for Ki67 and the active form of caspase 3, markers of proliferation, and apoptosis, respectively. Virus-treated, clotted tumors exhibited less proliferation and more apoptosis relative to tumors treated with VSV and heparin. Staining is expressed as percent positive pixels ×10 (mean + SEM). *P < 0.005, **P < 0.05.