(a) MV-eGFP-Pwt accelerated tumor regression of established subcutaneous ARH-77 xenografts in SCID mice, compared to MV-eGFP. Mice received two i.v. injections of viruses, each dose of 4 × 106 TCID50. Numbers of mice per treatment groups are n = 8 (MV-eGFP), n = 9 (MV-eGFP-Pwt), and n = 8 (control saline). Error bars indicate SEM. (b) Systemic virotherapy of KAS6/1 myeloma xenografts caused significant inhibition of tumor growth with both administered viruses. Viruses were applied i.v. four times 1 × 107 TCID50. Number of mice per treatment groups are n = 9 (MV-eGFP), n = 10 (MV-eGFP-Pwt), and n = 9 (control saline). Error bars indicate SEM. (c) Confocal microscopy of MV-eGFP-treated and MV-eGFP-Pwt-treated KAS6/1 tumors revealed large syncytia of infected tumors.