In vivo antitumor effect in human MPM xenograft models. (A) After tumor establishment, 6 mice per group were randomized to daily receive sorafenib 5 mg/kg/day, everolimus 1 mg/kg/day, their combination or vehicle alone. Tumor volume was monitored as described in the “material and methods” section and is reported in graph as mean ± St. Dev (Y error bar). *, p < 0.05 vs vehicle alone; †, p < 0.05 vs either single agent and vehicle alone. (B) Vascular specific CD31 staining and (C) TUNEL assay on vehicle (NT), everolimus 1 mg/kg/day (EV), sorafenib 5 mg/kg/day (SOR), and combination (CB) treated xenografts.