PDCD1 and cancer: As delineated in Figure 1D, our findings suggested that immunotherapy could potentially drive the differentiation of Tpex cells into Teff and Tex cells, thereby pivoting the regulatory dynamics of target genes from Eomes to Tbx21. Notably, the ratio of infiltrating Tpex cells within the TME has emerged as a crucial biomarker for gauging the effectiveness of anti-PD-1 therapy in a myriad of cancer patients (15).