CTSC and neoplasm: Statistical analysis showed that the expression levels (IHC staining scores) of all four proteins were significantly higher in the tumor parts than in the adjacent non-tumor parts (89.13 ± 49.8 vs. 52.35 ± 30.96, p < 0.001 for AGRN; 75.71 ± 54.11 vs. 35.45 ± 32.18, p < 0.001 for CTSC; 203.6 ± 88.27 vs. 70.05 ± 63.89, p < 0.001 for ERAP2 and 56.78 ± 55.4 vs. 3.3 ± 5.7, p < 0.001 for GPNMB) (Figure 6C).