Fig. 7

Targeting PAK1 by IPA-3 abrogates ESCC cell growth and metastasis in nude mice. a The growth curves of subcutaneous xenografts of KYSE150 cells are shown. Nude mice bearing KYSE150 xenograft tumors were treated with vehicle or IPA-3 (5 mg/kg) from day 6 to 20 after inoculation of KYSE150 cells. Points, mean; error bar, SD. n = 8 per group. *P < 0.05, **P < 0.01, ***P < 0.001 by Student’s t test. b After 14-day of IPA-3 treatment, the mice were sacrificed, tumors were dissected, weighed and photographed. Top, representative tumors from the control and experiment group are shown; bottom, comparison of tumor weights in control and experimental group (n = 8 per group). **P < 0.01 by Student’s t test. c Immunohistochemical analysis of p-PAK1 (T423), p-ERK1/2 (T202/Y204) and Ki67 in xenograft tissues from mice. Hematoxylin and eosin (H&E)-stained serial sections of the same xenografts are presented. Scale bars: 50 μm. d Immunoblotting of the p-PAK1 (T423), PAK1, p-PAK2 (S141), PAK2, Raf1, p-Raf1 (S338), MEK1, p-MEK1 (S298), ERK1/2 and p-ERK1/2 (T202/Y204) proteins in xenograft tissues is shown. e KYSE150 cells were intravenously injected into nude mice via the tail vein. Left, representative images of excised lungs after 6 weeks injection (arrows indicate the metastatic nodules). Right, graph showing the number of surface metastatic foci in the lungs. Error bars represent mean ± SD (n = 8 per group). f Lung metastases in each mice were confirmed by H&E staining. Arrows indicate the metastatic colonization of tumor cells in the lung tissues (left panel). The number of lung tumor nests in each group was counted and presented by mean ± SD (n = 8 per group) (right panel). Scale bars, 500 μm. **P < 0.01, ***P < 0.001 by Student’s t test