LDLR and cancer: The interactions of TG2 with platelet-derived growth factor receptor (PDGFR), vascular endothelial growth factor (VEGF), low density lipoprotein receptor (LDLR), G protein-coupled receptor 56 (GPR56), matrix metalloproteinase2 (MMP2), milk fat globulin EGF factor 8 (MFG-E8) were identified in various cancer cells, but have not been reported in breast cancer field, which provide the reference for further study.