Fig 6. Pharmacological inhibition of Wnt/β-catenin pathway represses sphere formation, stemness and radioresistance of glioma cells.
A, SW1783 and SW1088 cells infected with sg-SFRP2-1 or sg-NC lentiviral particles were seeded in 6-well plates (1 × 106/well), and treated with 1 μM XAV-939 or equal volume of DMSO (Veh) for 24 h. The protein expression of indicated genes was evaluated by western blot. B-C, SW1783 and SW1088 cells were introduced with sg-SFRP2-1 or sg-NC lentiviral particles, then seeded in 6-well plates at 8000/well for soft agar assay. Cells were treated with 1 μM XAV-939 or equal volume of DMSO (Veh) at the same time. Representative plates (B) and average number of colonies per well (C) were shown. D-E, SW1783 and SW1088 cells were introduced with sg-SFRP2-1 or sg-NC lentiviral particles, then seeded in 6-well plates at 3000/well for sphere formation assay. Cells were treated with 1 μM XAV-939 or equal volume of DMSO (Veh) at the same time. Representative images (D) and average number of spheres per image (E) were shown. F, SW1783 and SW1088 cells introduced with sg-SFRP2-1 or sg-NC lentiviral particles were treated with 1 μM XAV-939 or equal volume of DMSO (Veh) for 6 d, then the expression of Oct4, Lin28, Nanog and Sox2 was evaluated by qRT-PCR. G, SW1783 and SW1088 cells introduced with sg-SFRP2-1 or sg-NC lentiviral particles were seeded in 96-well plates (3000/well) and treated with 2 or 4 Gy X-ray irradiation, 1 μM XAV-939 or equal volume of DMSO (Veh) as indicated. Cell viability was tested at 72 h after the irradiation. H-J, SW1783 cells (2 × 106) infected with sg-SFRP2-1 or sg-NC lentiviral particles were subcutaneously injected into nude mice. Tumor xenografts were treated with 2 Gy X-ray irradiation, 25 mg/kg XAV-939 or equal volume of 50% PEG-400 as indicated daily for three weeks from day 7. Tumor growth curves (H), image of tumor xenografts (I) and tumor weight (J) were shown. *P< 0.05, **P< 0.001. n.s., not significant.