ANGIO-TUMORAL LAMININ IN MURINE TUMORS DERIVED FROM HUMAN-MELANOMA CELL-LINES - IMMUNOHISTOCHEMICAL AND ULTRASTRUCTURAL OBSERVATIONS

Citation
C. Lugassy et al., ANGIO-TUMORAL LAMININ IN MURINE TUMORS DERIVED FROM HUMAN-MELANOMA CELL-LINES - IMMUNOHISTOCHEMICAL AND ULTRASTRUCTURAL OBSERVATIONS, Journal of submicroscopic cytology and pathology, 30(2), 1998, pp. 231-237
Citations number
51
Categorie Soggetti
Cell Biology",Pathology
ISSN journal
11229497
Volume
30
Issue
2
Year of publication
1998
Pages
231 - 237
Database
ISI
SICI code
1122-9497(1998)30:2<231:ALIMTD>2.0.ZU;2-C
Abstract
Cells in tissues interact with each other and with the extracellular m atrix as part of a structural and informational unit. During cancer pr ogression, tumor cells participate in the formation of a neotissue inv olving other cells and matrix. We recently observed in melanoma an ass ociation between tumor and endothelial cells via an amorphous matrix c ontaining free laminin. The pericytic location of melanoma cells in th is angio-tumoral complex raised the question of an intramesenchymal mi gration of metastatic melanoma cells promoted by free laminin along th e endothelium. However the respective roles of melanoma cells and endo thelial cells in laminin secretion were not clear. In an attempt to cl arify the latter issue, we injected into mice three human melanoma cel l lines, one secreting laminin and two that did not, in order to ident ify the source of laminin secretion in the subsequent interactions bet ween tumor cells and vascular endothelium. Using immunohistochemistry and electron microscopy we observed in all three cases an amorphous ma trix containing laminin between tumor and endothelial cells. The fact that two cell lines did not secrete laminin suggests that the periendo thelial/peritumoral laminin could be of endothelial origin. Given the presence of laminin alone during intramesenchymal angiogenesis and emb ryogenesis, we propose an analogous role for endothelial laminin in fa cilitating the migration of melanoma cells along the abluminal surface of the endothelium.