In vivo antitumor efficiency of STP-NG/SHK against lung osteosarcoma metastasis. (A) Macroscopic appearance of lung metastatic osteosarcoma tumors per group. Scale bar = 1 cm. (B) Lung weight and (C) average microscopically (largest coronal sections) counted lung metastases. (D) H&E staining of metastases of osteosarcoma tumors. Arrows indicate lung metastases. Scale bar = 2 mm. (E) RIP1, RIP3, PARP, caspase-3, and caspase-8 expression in harvested lung metastases per group measured by Western blot and (F) semiquantitative analyses. Each set of data is represented as mean ± SEM (for B and C, n = 7; for E, n = 3; *P < 0.05, #P < 0.01, &P < 0.001).