MSTN and cancer: Circulating myostatin was negatively correlated with weight loss in patients with cancer (p < 0.01).<h4>Conclusion</h4>These data provide proof-of-principle that mechanistically distinct approaches targeting muscle anabolism and appetite may act additively with GDF-15 neutralization, particularly in cancer cachexia settings with lower GDF-15 dependence.<h4>Trial registration</h4>ClinicalTrials.gov identifier: NCT01360554.