GDF15 and cancer: Given the elevated plasma GDF15 levels in POLG animals and the efficacy of an anti‐GDF15 antibody (mAB2) treatment in preserving muscle mass and function in cancer cachexia models from our previous studies [14], we decided to investigate whether GDF15 neutralization with an anti‐GDF15 monoclonal antibody, mAB2, may alleviate muscle atrophy and exercise intolerance in POLG mice.