Morphological analysis of tumor cell/endothelial cell interactions under shear flow.
In the process of hematogenous cancer metastasis, tumor cells (TCs) must shed into the blood stream, survive in the blood circulation, migrate through the vascular endothelium (extravasation) and proliferate in the target organs. However, the precise mechanisms by which TCs penetrate the endothelial cell (EC) junctions remain one of the least understood aspects of TC extravasation. This question has generally been addressed under static conditions, despite the important role of flow induced mechanical stress on the circulating cell-endothelium interactions. Moreover, flow studies were generally focused on transient or firm adhesion steps of TC-EC interactions and did not consider TCs spreading or extravasation. In this paper, we used a parallel-plate flow chamber to investigate TC-EC interactions under flow conditions. An EC monolayer was cultured on the lower plate of the flow chamber to model the endothelial barrier. Circulating TCs were introduced into the flow channel under a well-defined flow field and TC cell shape changes on the EC monolayer were followed in vitro with live phase contrast and fluorescence microscopy. Two spreading patterns were observed: radial spreading which corresponds to TC extravasation, and axial spreading where TCs formed a mosaic TC-EC monolayer. By investigating the changes in area and minor/major aspect ratio, we have established a simple quantitative basis for comparing spreading modes under various shear stresses. Contrary to radial spreading, the extent of axial spreading was increased by shear stress.
Laboratoire de Spectrométrie Physique, UMR 5588 (CNRS- Université Grenoble I) BP 87, 140 Rue de la Physique, Saint-Martin d'Hères 38402, France. roxana.chotard@ujf-grenoble.fr
Roxana
R
Chotard-Ghodsnia
Oualid
O
Haddad
Anne
A
Leyrat
Agnès
A
Drochon
Claude
C
Verdier
Alain
A
Duperray
D001696:Biomechanical Phenomena; D002277:Carcinoma / Q000378:metabolism / Q000473:pathology*; D002450:Cell Communication / Q000502:physiology*; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D009362:Neoplasm Metastasis / Q000473:pathology; D001749:Urinary Bladder Neoplasms / Q000378:metabolism / Q000473:pathology*