Fig. 3: Tenascin-c (TNC) knockdown attenuated vasculogenic mimicry (VM) formation in vitro and in vivo.

a Total RNA was isolated from the shNC, sh#1, and sh#2 groups of U251 and A172 cells and analyzed via RT-qPCR. TNC mRNA was significantly downregulated (p < 0.01; GAPDH used as the control). b Western blot analysis revealed that TNC was significantly downregulated (β-actin used as the loading control). c The number of VM structures in both the sh#1 and sh#2 groups of U251 and A172 glioma cells was decreased in comparison with that in the shNC group. Scale bar = 100 μm. d, e Exogenous TNC exposure for 8 h increased the number of VM structures in both the sh#1 and sh#2 groups of U251 and A172 glioma cells. Scale bar = 100 μm. f, g TNC knockdown inhibited tumorigenicity in U251 glioma cells. h Quantification of tumor mass in the shNC, sh#1, and sh#2 groups. i Representative images of hematoxylin-eosin staining and CD31/periodic acid–Schiff (PAS) staining (the red arrows indicate typical VM channels; the black arrows indicate classical endothelial cell vessels). j Quantification of VM channels via CD31/PAS staining in the shNC, sh#1, and sh#2 groups (magnification: ×400; scale bar = 50 μm). k HE staining of brain sections demonstrated a significant decrease in tumor volume after TNC-knockdown at 25 days post implantation (black arrows indicate tumor location). l Kaplan–Meier survival curves showing a significant increase in median survival of TNC-knockdown tumor-bearing mice. Scale bar = 500 μm (*p < 0.05, **p < 0.01, ***p < 0.001).