STAT3 and neoplasm: The recently described modulating effects of the diarylheptanoid curcumin on STAT3 and JAK2 signalling, leading to a decreased production of IL-6 in MDSCs, could also be beneficial in combined therapies while eliciting no adverse effects.115 Several attempts to apply STAT3 inhibitors in clinical studies for targeting tumour-associated myeloid cells were hindered by the unexpected adverse effects and limited efficacy of these compounds.116 More recent approaches aim to interfere with STAT3 mRNA by the administration of siRNA or decoy oligonucleotides.