In order to prove that the observed increased anti-leukemic effects upon combined inhibition of GLI, FLT3 and PI3K are mediated via inhibition of the GLI cascade, we produced several AML cell lines expressing the luciferase gene under the control of GLI transcriptional response elements which allows a direct monitoring of the GLI promotor activity. The gene discussed is GLI1; the disease is acute myeloid leukemia.