T-ALL human xenograft samples with GLI1 expression are sensitive to hedgehog inhibitors ex vivo. (A) Quantitative reverse transcription polymerase chain reaction data showing the relative expression level of GLI1 in 17 patient-derived T-ALL xenograft samples. (B) T-ALL samples with detectable GLI1 expression (left) or very low to undetectable GLI1 expression (right) were cultured ex vivo and treated with GDC-0449, GANT61, or vehicle (DMSO). Diagrams depict the survival rate of the T-ALL samples relative to DMSO-treated cells. (C) Relative expression of GLI1, BCL2, and PTCH2 in untreated cells vs cells treated with GDC0449 or GANT61.