IL2 and cancer: Cachexia is a comorbidity condition in elderly cancer patients (Ali and Garcia, 2014) and can impair the host’s ability to tolerate anti-cancer treatments (Ross et al., 2004; Aapro et al., 2014; Kimura et al., 2015), as seen in the present study by rapid weight loss with IL-2/anti-CD40 immunotherapy for the elderly mice.