Fig. 5. GLT8D1 promotes Wnt/β-catenin signaling.

a Wnt signaling response luciferase reporter TOPFlash was examined in GSC11 cells after Wnt3a or LiCl treatment. b The β-catenin, LaminB and GAPDH proteins were examined by IB with indicated antibodies in GSC11 cells. c The mRNA expressions of indicated genes in GSC11 cells were examined by qRT-PCR after PBS or NH₄Cl treatment. Mock=PBS treatment. d Immunofluorescent staining of β-catenin proteins in GSC11 cells expressing GLT8D1 knockdown or control shRNAs. White arrows: β-catenin nuclear-accumulated signals. Scale bar: 50 μm. CD133 forced overexpression in GLT8D1 knockdown cells (e) promotes cell proliferation (f), and tumor sphere formation (g) in GSC11. h Cellular apoptosis was determined using Annexin V staining followed by FACS analysis in GSC11 cells treated by DMSO or TMZ. i Cell lysates were examined by IB with indicated antibodies. tPARP = total PARP, cPARP = cleaved PARP. CC3 = cleaved caspase 3. j The scheme for xenograft tumors generated from GSC11 cells responding to TMZ, TMZ: 60 mg kg⁻¹, once a week for 5 weeks. k–m GLT8D1 knockdown tumors were more sensitive to TMZ treatment compared to control shRNA tumors. Indicated xenograft tumor masses were harvested, representative xenograft tumors are pictured (k), weights (l) and tumor volumes (m) were shown. Means ± SEM, *P < 0.05, **P < 0.01, ***P < 0.001, t-test.