atherosclerosis by modulating the activity and cellular localization of the PDGFR-β in vascular smooth muscle cells. Finally, LRP1 in macrophages has an effect on atherosclerosis through the modulation of the extracellular matrix and inflammatory responses. Cancer LRP1 is involved in tumorigenesis, and is proposed to be a tumor suppressor. Notably, LRP1 functions in clearing proteases such as plasmin, urokinase-type plasminogen activator, and metalloproteinases, which contributes to prevention of cancer invasion, while its absence is linked to increased cancer invasion. However, the exact mechanisms require further study, as other studies have shown that LRP1 may also promote cancer invasion. One possible mechanism for the inhibitory function of LRP1 in cancer involves the LRP1-dependent endocytosis of 2′-hydroxycinnamaldehyde (HCA), resulting in decreased pepsin levels and, consequently, tumor progression. Alternatively, LRP1 may regulate focal adhesion disassembly of cancer cells through the ERK and JNK pathways to aid invasion. Moreover, LRP1 interacts with PAI-1 to recruit mast cells (MCs) and induce their degranulation, resulting in the release of MC mediators, activation of an inflammatory response, and development of glioma. Interactions LRP1 has been shown to interact with: A2-Macroglobulin, β-amyloid precursor protein, APBB1, APOE, Aprotinin, C1S/C1q inhibitor, CALR, CD44, Chylomicron, Circumsporozoite protein, Collectin, Complement C3, CTGF, DLG4, Elastase, Factor IXa, Factor VIIa, Fibronectin, Gentamicin, GIPC1, Heat shock proteins: gp96, hsp70, hsp90, heparin cofactor II, Hepatic lipase, ITGB1BP1, Lactoferrin, Lipoprotein lipase, LPL, MAPK8IP1, MAPK8IP2, Midkine, MMP13, MMP2, MMP9, Neuroserpin, Nexin-1, NOS1AP, PAI 2, PAI-1, PDGF, tPA, uPA, Polymyxin B, Protein C inhibitor, Pseudomonas exotoxin A, RAP, Ricin A, SHC1, and Sphingolipid activator protein, SYNJ2BP. Tat, Thrombin, THBS1, Thrombospondin 2, TIMP1, TIMP2, TIMP3, Tissue factor pathway inhibitor, PLAT, Transforming growth factor-β, PLAUR, VLDL, Interactive pathway map See also Cluster of differentiation Low density lipoprotein receptor gene family References Further reading External links Clusters of differentiation