The activation status of HH signaling is highly diverse in CLL. (A) IHC stainings from CLL BM samples for GLI1, SMO, and the HH ligands SHH/IHH. Negative (left) and positive (right) examples for expression of GLI1, SMO, and the HH ligands in CLL. Original magnification ×40 for GLI1 (scale bar, 50 μm) and ×100 for others (scale bar, 25 μm). Microscope: Axioplan 2 (Zeiss); GLI1 40×/0.95 NA; SMO + SHH/IHH 100×/1.25 NA oil objective, room temperature; microscope software: AxioVision LE. (B) Percentage of samples positive or negative for IHC staining for GLI1, SMO, and the HH ligands SHH/IHH and DHH in 24 CLL cases (single patient information, including scoring; supplemental Table 3). (C) qPCR for GLI1 and PTCH1 in peripheral blood samples from patients with CLL. Transcript levels are shown relative to GAPDH and compared with the median of all samples (patient single data; supplemental Table 4). (D) Correlation in between GLI1 and PTCH1 transcript levels in same patients with CLL as in panel C shows a positive correlation between both genes (n = 18; P = .0022, Spearman correlation coefficient, r = 0.67321).