STAT3 and neoplasm: As expected for this model, the muscle‐specific E3 ligases atrogin‐1 (FBXO32) and MuRF‐1(TRIM63) were induced in skeletal muscles of tumor‐bearing animals (Bonetto et al, 2011; Tseng et al, 2015a) as was the STAT3 target gene and regulator of atrogin‐1 and MuRF‐1, CEBPδ (CEBPD; Silva et al, 2015).