PDCD1 and sarcoma: Other crucial pathways in which PD-L1 interferes are phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) and rat sarcoma/mitogen-activated protein kinase/extracellular signal-regulated kinase (Ras/MEK/Erk) binding to PD-1 reduce TCR-mediated signaling, thereby disrupting them [25,30,35].