Fig. 7

Functions associated with nodal metastasis. A Bar graph of significant MSigDB hallmark gene sets associated with NST with nodal metastasis, obtained through GSEA (p < 0.05). Bar colors indicate positive (pink) or negative (blue) values of normalized enrichment scores. B GSEA of gene sets related to the EMT and stem cells in NST specimens with and without nodal metastasis. C Bar plots representing the immunohistochemical verification of PDGFRA and CAV1 expression in the 27 MpBC cases with or without lymph node metastasis (chi-square test). D Representative pictures of immunohistochemical staining for PDGFRA and CAV1. Positive staining in ≥ 5% of tumor cells is considered positive. PDGFRA staining in the myoepithelial (star) cells surrounding the nonneoplastic mammary ducts, which serves as an internal positive staining control. CAV1 staining is also observed in vessels. In cases BT15, CAV1 staining is completely negative in the NST component, in contrast to the intense staining in the SPS component