Furthermore, PAL restored the phosphorylation level of mTOR (p < 0.001), as well as the mRNA expression of myosin heavy chain (p < 0.01).<h4>Conclusions</h4>Our findings demonstrate that Ido1 accelerates muscle atrophy and cancer cachexia by driving a metabolic reprogramming centred on the Trp-Kyn pathway. Here, MTOR is linked to cancer.