Validation of the NRG signature in an external clinical cohort. The expression of 6 selected NRGs (IPMK, SLC39A7, FASLG, HSP90AA1, FLT3, LEF1) (A) and immune checkpoints (PD-1, PD-L1, and CTLA-4) (B) in the two groups were detected using qRT-PCR. Immunohistochemistry was used to compare the expression of PD-1 (C), PD-L1 (D), CTLA-4 (E), and IPMK (F) in the two risk groups. G The co-expression of CD206 and IPMK was detected using immunofluorescence. ns, not significant; *P < 0.5; **P < 0.01; ***P < 0.001.