SIRT6 and neoplasm: In non‐tumour mice, SIRT6 over‐expression did not influence Wnt4 mRNA expression (Figure6A); however, in tumour‐bearing mice, gastrocnemius muscles of Tu‐Sk.T6Tg mice showed a significant downregulation of Wnt4 mRNA levels, compared with that in Tu‐CN mice (Figure6B).