CCN4 and breast cancer: qPCR was used to confirm the identified BC biomarkers (gene signatures) by determining the relative expression of 16 genes (nine-gene signature for diagnosis: COL10A, S100P, ADAMTS5, WISP1, COMP, CXCL10, LYVE1, COL11A1, and INHBA; and eight-gene signature for prognosis: CCNE2, NUSAP1, TPX2, S100P, ITM2A, LIFR, TNXA, and ZBTB16), with an overlap of the S100P gene (Figure 11).