PDCD1 and cancer: On the other hand, CCR-associated clusters showed higher expression of naive T cell marker genes (LEF1, TCF7, CCR7, SELL), microtubule-associated gene; RPL4151, scaffold protein gene; ABLIM1 (Fig. 4f), The pathway analysis of relapse-associated cluster’s upregulated DEGs revealed significant upregulation (P < 0.05) of multiple immune regulatory pathways including Th1 pathway, calcium-induced T lymphocyte apoptosis, and to a lesser extent, upregulation of T cell exhaustion pathway with downregulation of PD-1 and PD-L1 cancer immunotherapy pathways (Fig. 4g).