Pharmacological inhibition of the hedgehog pathway decreases the chemoresistance in T-ALL cell lines that are sensitive to hedgehog inhibitors. (A) Relative proliferation of a sensitive cell line (ALL-SIL, top) and of an insensitive cell line (P12-Ichikawa, bottom) to GANT61. (B) IC₅₀ values of T-ALL cell lines treated with ARA-C, ARA-C and 5 μM of GANT61, doxorubicin, or doxorubicin and 5 μM of GANT61. Cell lines sensitive to GANT61 treatment are shown in red; insensitive cell lines are shown in blue. (C) Diagrams showing the relative proliferation of a sensitive cell line (ALL-SIL, top) and of an insensitive cell line (P12-Ichikawa, bottom) to GDC-0449. (D) IC₅₀ values of T-ALL cell lines treated with ARA-C, ARA-C and 5 μM of GDC-0449, doxorubicin, or doxorubicin and 5 μM of GDC-0449. Cell lines sensitive to GDC-0449 treatment are shown in red, insensitive cell lines are shown in blue.