To address the possible role of endogenous, physiological oncogenic GLI activity, we performed RNA-interference (RNAi)-mediated GLI1 inactivation in human BRAFV600E mutated melanoma cells (WM35) and treated the cells with IL6 [75 ng/mL] for 18 h to activate IDO1 expression via STAT3. Here, IDO1 is linked to melanoma.