GDF15 and cancer: Additional recommendations for future research are to apply the principles and tools used in the current study to other novel biomarkers including GDF-15, FGF-21, fractakline, IFN-gamma, IL-10, IL-16, M-CSF, and MPIF-1 (CCL23) and transforming growth factor β1 to be investigated in both cachectic and non-cachectic cancer patients.