Abstract
The multi-step process of the emigration of cells from the blood stream through the vascular endothelium into the tissue has been termed extravasation. The extravasation of leukocytes is fairly well characterized down to the molecular level, and has been reviewed in several aspects. Comparatively little is known about the extravasation of tumor cells, which is part of the hematogenic metastasis formation. Although the steps of the process are basically the same in leukocytes and tumor cells, i.e. rolling, adhesion, transmigration (diapedesis), the molecules that are involved are different. A further important difference is that leukocyte interaction with the endothelium changes the endothelial integrity only temporarily, whereas tumor cell interaction leads to an irreversible damage of the endothelial architecture. Moreover, tumor cells utilize leukocytes for their extravasation as linkers to the endothelium. Thus, metastasis formation is indirectly susceptible to localization signals that are literally specific for the immune system. We herein compare the extravasation of leukocytes and tumor cells with regard to the involved receptors and the localization signals that direct the cells to certain organs and sites of the body.
Highlights
General steps of the extravasation process The extravasation is a multi-step process of the emigration of cells from the blood stream into the tissue
A further important difference is that leukocyte interaction with the endothelium changes the endothelial integrity only temporarily, whereas tumor cell interaction leads to an irreversible damage of the endothelial architecture
We compare the extravasation of leukocytes and tumor cells with regard to the involved receptors and the localization signals that direct the cells to certain organs and sites of the body
Summary
General steps of the extravasation process The extravasation is a multi-step process of the emigration of cells from the blood stream into the tissue. An other group has described N-cadherin to be involved in the transmigration process [40] It seems that in the case of tumor cells, there is not such a clear difference between the receptors used for rolling, adhesion and diapedesis as it is for leukocytes. CEA: carcinoembrionic antigen; CLA: cutanous lymphocyte antigen; CRD: carbohydrate-recognition domains; ECM: extracellular matrix; GPCR: G proteincoupled receptor; HCELL: hematopoietic cell E-/L-selectin ligand; HEV: high endothelial venules; HUVEC: human umbilical vein endothelial cells; ICAM: intercellular adhesion molecule; Ig: immunoglobuline; IL: interleukin; JAM: junctional adhesion molecule; LFA: leukocyte function-associated antigen; MadCAM: mucosal adressin cell adhesion molecule; MMP: matrix-metalloproteinase; NK cells: natural killer cells; PECAM: platelet/endothelial cell adhesion molecule; PSGL: P-selectin glycoprotein ligand; SDF: stromal cell-derived factor; TA: Thomsen-Friedenreich antigen; TARC: thymus- and activation-regulated chemokines; TNF: tumor necrosis factor; VCAM: vascular cell adhesion molecule; VLA: very late activation antigen
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
