Fig. 4
Gimatecan inhibited tumor growth of xenografts on PDX models in vivo. a Gimatecan significantly inhibited tumor growth in xenografts from all five PDX models. A PDX model was established by subcutaneously transplanting tumor tissues of a patient into NOD/SCID mice and PDX 1–5 indicated PDX models from 5 different GC patients. PDX tissues were subcutaneously inoculated into mice, and when the tumor size reached 150–250 mm3, mice (n = 5 in each group) were treated with buffer control or inhibitors. Tumor volumes were presented as mean ± SD. The antitumor activity is depicted by tumor growth inhibition (TGI). TGI = ΔT/ΔC × 100% (ΔT = tumor volume change of the drug-treated group, ΔC = tumor volume change of the control group on the final day of the study). *p < 0.05, **p < 0.01, ***p < 0.001. b Immunohistochemical staining for Ki-67 of xenografts on day 22 of treatment from four PDX models. The ki-67 index, marker of cell proliferation, was calculated as the proportion of positive tumor cell nuclei in all tumor cells examined and labeled in red in the images. Scale bar represents 100 µm