Characterization of human xenografts and Vaccinia Virus signatures. (A) Representative growth curves (n = 8 animals) for 2 xenografts from HT-29 and GI-101A cell lines; red dots represent control, green boxes the post treatment groups; for further details about the xenograft model refer to references [9, 13]. (B) Viral titer (PFU/gram of xenograft; n = 4) comparing the permissivity of 3 xenografts derived from GI-101A, HT-29 and PC-3 cell line whose responsiveness is under characterization 7, 21 and 42 days after GLV-1h68 administration. (C, left) Scatter plot correlating the level of Renilla luciferase-Aequorea green fluorescent protein messenger RNA expression with the presence call of probes above the set threshold level for the VACV expression array platform. VACV gene expression in non-infected PC-3, HT-29 and GI-101A xenografts was compared to infected xenografts 1, 7 (GI-101A only), 21 and 42 days before. High presence call (> 40%) in the non-infected xenografts could be expected due to the large number of mouse and human housekeeping genes present in the array platform); R2 value refers to the correlation between RUC-GFP expression and number of VACV transcripts significantly up regulated in the same experiment. (C, right) Scatter plot as per panel C, left, comparing in vitro VACV gene expression of GLV-1h68-infected HT-29 and GI-101A cell lines at 6 and 12 hours with controls. (D) A Venn diagram displays the extent of overlap among VACV-specific probes (top) and VACV genes (bottom) differentially expressed by infected GI-101A xenografts at day 21 and 42 compared with day 1 after GLV-1h68 injection.