CLDN4 and neoplasm: By analyzing the differential genes between P-LN and tumor 3, we found that macrophages in P-LN exhibited high expression of IGHG, IGLC2, IGKC, IGHG1, CD52, CD1B, MRC1, SPP1, and LGALS2, whereas the primary tumor exhibited high express ion of SDS, FABP4, SPRR3, CLDN4, MDK, and IFI27 (Figure 4D; Supplementary Table S1).