We determined whether CAFs from luminal tumors presented phenotypic variability at their basal expression of several genes implicated in tumor progression (S100A4, FGF2, FGF7, HGF, PDGFA, PDGFB, TGFβ, VEGFA, IGF2, IL6, IL8, CCL2, CXCL12, uPA, MMP2, MMP9, MMP11, NFκB, and TIMP1). The gene discussed is IL6; the disease is neoplasm.