MTOR and cancer: Switching from calcineurin to mTOR inhibitors is an interesting strategy in this context with the objective of uncoupling anti-PD-1 therapy toxicity and efficacy, as mTOR inhibitors have been shown to induce Treg expansion [71,72], have an independent antitumor effect [73] and are associated with fewer incidents of cancer occurrence compared to calcineurin inhibitors [74,75,76].