CTSC and hepatocellular carcinoma: TIMER2.0 database analysis pinpointed PRDM1 as having the strongest correlation with M2 macrophage infiltration (r = 0.691), followed by TREM2 (r = 0.604), PLXDC2 (r = 0.528), and CTSC (r = 0.516), highlighting their potential as biomarkers or therapeutic targets in HCC treatment strategies focused on modulating the tumor microenvironment (Figures 5(b) and 5(c)).