Fig. 7

Oncolytic activity and safety of PD-SK-375TS and PD-H-375TS in nude mice with Colo320 cell tumors. Colo320 tumors were established on both flanks of Balb/C nude mice, when the tumor size reached ∼ 0.5 cm, one of the tumors was injected with 3 × 10⁶ PFU PD-SK-375TS (n = 5) or PD-H-375TS (n = 5) or with PBS (n = 5) while the contralateral tumor remained untreated. All animals were sacrificed 13 days later and investigated. (A) Time course of virus application and analysis. (B) Development of animal weight. (C) Growth of the injected tumor. Left, shows mean values ± SEM for each group; right, data from PD-SK-375TS and PD-H-375TS of the left diagram for each animal. Significance PD-SK-375TS vs. PD-H-375TS, * p < 0.05; ** p < 0.01. Significance, PD-SK-375TS vs. PBS, ^#p < 0.05; ^##p < 0.01. The dashed lines indicate the times at which the viruses were injected. (D) Growth of the non-injected contralateral tumor. Left, shows mean values ± SEM for each group; right, data from PD-SK-375TS and PD-H-375TS of the left diagram for each animal. (E) Representative images of explanted left and right tumors of PD-SK-375TS and PD-H-375TS; * marks the injected tumor. Scale bar = 1 cm. (F) Distribution of PD-SK-375TS and PD-H-375TS in indicated organs and in the injected and untreated contralateral tumors. Left diagram: PD-H-375TS and PD-SK-375TS titers determined by plaque assay on HeLa cells. Right diagram: Virus genome copy number in the pancreas determined by quantitative RT-PCR. (G) Histological examination of heart and pancreas. Shown are representative tissue slides after staining with H&E