title: Pericytic-like angiotropism of glioma and melanoma cells.
abstract: We have identified in malignant melanoma an angiotumoral complex in which tumor cells occupy a pericytic location along the endothelium of microvessels without evidence of intravasation. We have suggested that this pericytic-like angiotropism could be a marker of an extravascular migration of tumor cells along the abluminal surface of vessels. The extravascular migratory metastasis proposed for melanoma has close analogies with glioma migration. To compare our hypothesis of extravascular migration by melanoma with the migration of glioma cells, we have used the B16 murine melanoma cell line and the GL26 murine glioma cell line in an in vivo murine brain tumor model and in vitro using endothelial cells that have formed capillary-like structures and have been cocultivated with tumor cells. In the brain tumors, a clear progression of glioma and melanoma cells was observed along the abluminal surface of vessels, where they occupied a pericytic location along the periendothelial laminin. In vitro, time-lapse videomicroscopy recorded the migration of tumor cells toward endothelial tubules. After 24 hours, both the melanoma cells and the glioma cells were localized along the external surfaces of the vascular tubules, occupying a pericytic-like location. These similarities between glioma and melanoma support the hypothesis of an extravascular migration of melanoma cells, particularly along the abluminal surface of vessels.
authors.affiliation: Department of Dermatology, George Washington University Medical Center, The George Washington University, Washington, District of Columbia 20037, USA.
authors.forename: Claire
authors.initials: C
authors.lastname: Lugassy
authors.forename: Raymond I
authors.initials: RI
authors.lastname: Haroun
authors.forename: Henry
authors.initials: H
authors.lastname: Brem
authors.forename: Betty M
authors.initials: BM
authors.lastname: Tyler
authors.forename: Robert V
authors.initials: RV
authors.lastname: Jones
authors.forename: Patricia M
authors.initials: PM
authors.lastname: Fernandez
authors.forename: Steven R
authors.initials: SR
authors.lastname: Patierno
authors.forename: Hynda K
authors.initials: HK
authors.lastname: Kleinman
authors.forename: Raymond L
authors.initials: RL
authors.lastname: Barnhill
mesh_terms: D001932:Brain Neoplasms / Q000098:blood supply / Q000378:metabolism / Q000473:pathology*; D002465:Cell Movement; D005910:Glioma / Q000098:blood supply / Q000378:metabolism / Q000473:pathology*; D007797:Laminin / Q000378:metabolism; D008546:Melanoma, Experimental / Q000098:blood supply / Q000378:metabolism / Q000473:pathology*; D018715:Microscopy, Video; D009362:Neoplasm Metastasis / Q000473:pathology / Q000503:physiopathology; D009389:Neovascularization, Pathologic; D020286:Pericytes / Q000378:metabolism / Q000473:pathology*; D012878:Skin Neoplasms / Q000098:blood supply / Q000378:metabolism / Q000473:pathology*; D014407:Tumor Cells, Cultured
chemical_list: D007797:Laminin