*4.14. Immunohistochemistry*

Immunohistochemical staining was adapted from previously described protocols [35]. Formalin-fixed and paraffin-embedded patient tissues were stained with antibodies against FPN (Novus, NBP1-21502) and CD163 (Abcam, Cambridge, UK, ab182422) according to the manufacturer's protocol using the Opal 4-color-automation IHC-kit (PerkinElmer, Rodgau, Germany, NEL820001KT). Images were acquired using the LSM 800 microscope (Zeiss) and edited using ImageJ software.

#### *4.15. Hematoxylin and Eosin Stain*

For hematoxylin and eosin staining, formalin-fixed and paraffin-embedded tissues were rehydrated, stained using Mayer's hemalum solution (Merck, 109249), washed, counter-stained using Eosin (Merck, 102439), and mounted in Entellan (Merck, 107961). An Axioskop 40 (Zeiss) was used to acquire images.

#### *4.16. XTT*

Cytotoxicity of iron chelators was tested by a photometric XTT assay (Panreac, Darmstadt, Germany, A8088). Briefly, sub-confluent cells were exposed to iron chelators for 12 h. Subsequently, XTT reagent was added and absorbance was measured at 450 nm vs. 630 nm according to manufacturer's protocol. Experiments were conducted in quintuplicates. Cell viability was normalized to the untreated control.
