STAT3 and mandibuloacral dysplasia: For example, downregulation of nuclear sirtuin, including SIRT1 and SIRT6, is known to enhance the expression of IL‐6.[30, 31] The elevation of IL‐6 levels in serum from MAD patients (Figure 1D) and in MAD‐iMSCs prompted further investigation into a recently identified noncanonical role of STAT3.