PD - 1/PD-L1 inhibitors work by disrupting this interaction, thereby restoring TCR and CD3-mediated co-stimulatory signaling, reactivating downstream PI3K/AKT and MAPK pathways, promoting T cell proliferation and activation, and ultimately counteracting tumor cell-mediated immunosuppression and inhibiting tumor growth and metastasis. The gene discussed is RPL17; the disease is neoplasm.