title: Tissue inhibitor of metalloproteinase-2 regulates matrix metalloproteinase-2-mediated endothelial barrier dysfunction and breast cancer cell transmigration through lung microvascular endothelial cells.
abstract: Matrix metalloproteinases (MMP) have been implicated in multiple stages of cancer metastasis. Tissue inhibitor of metalloproteinase-2 (TIMP-2) plays an important role in regulating MMP-2 activity. By forming a ternary complex with pro-MMP-2 and its activator MMP-14 on the cell surface, TIMP-2 can either initiate or restrain the cleavage and subsequent activation of MMP-2. Our recent work has shown that breast cancer cell adhesion to vascular endothelial cells activates endothelial MMP-2, promoting tumor cell transendothelial migration (TEM(E)). However, the mechanism of MMP-2 regulation during TEM(E) remains unclear. In the current study, we present evidence that MMP-14 is expressed in both invasive breast cancer cells (MDA-MB-231 and MDA-MB-436) and lung microvascular endothelial cells (HBMVEC-L), whereas TIMP-2 is exclusively expressed and released from the cancer cells. The tumor cell-derived TIMP-2 was further identified as a major determinant of endothelial MMP-2 activity during tumor cell transmigration in the presence of MMP-14. This response was associated with endothelial barrier dysfunction because coculture of MDA-MB-231 or MDA-MB-436 with HBMVEC-L caused a significant decrease in transendothelial electrical resistance concomitantly with endothelial cell-cell junction disruption and tumor cell transmigration. Knockdown of TIMP-2 or inhibition of TIMP-2/MMP-14 attenuated MMP-2-dependent transendothelial electrical resistance response and TEM(E). These findings suggest a novel interactive role of breast cancer cells and vascular endothelial cells in regulating the TIMP-2/MMP-14/MMP-2 pathway during tumor metastasis.
authors.affiliation: Division of Research, Department of Surgery, University of California at Davis School of Medicine, Sacramento, California 95817, USA.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Shen
authors.forename: Eugene S
authors.initials: ES
authors.lastname: Lee
authors.forename: Robert L
authors.initials: RL
authors.lastname: Pitts
authors.forename: Mack H
authors.initials: MH
authors.lastname: Wu
authors.forename: Sarah Y
authors.initials: SY
authors.lastname: Yuan
mesh_terms: D001943:Breast Neoplasms / Q000201:enzymology / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000502:physiology; D042783:Endothelial Cells / Q000201:enzymology / Q000378:metabolism / Q000473:pathology; D004730:Endothelium, Vascular / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D008168:Lung / Q000098:blood supply* / Q000378:metabolism / Q000473:pathology; D053511:Matrix Metalloproteinase 14 / Q000378:metabolism; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D009362:Neoplasm Metastasis; D034741:RNA, Small Interfering / Q000008:administration & dosage / Q000235:genetics; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D034741:RNA, Small Interfering; D019716:Tissue Inhibitor of Metalloproteinase-2; D020778:Matrix Metalloproteinase 2; D053511:Matrix Metalloproteinase 14