Expression of the endothelial adhesion molecule VCAM-1 was studied in human malignant melanoma lines by flout cytometry. Clones 214 and 2/14 (derived from the same lesion) had appreciable levels of VCAM-1 expression, whereas clone 2/21 and the lines A2058, Mel24, and A375 were negative. Clone 2114 was selected for further analysis. Exposure to tumor necrosis factor (TNF) markedly augmented VCAM-1 on melanoma cells. Surface VCAM-1 was associated with expression of specific transcripts that were augmented by TNF. Analysis by reverse transcriptase and polymerase chain reaction using appropriate primers revealed that TNF-stimulated melanoma cells expressed both 7 and 6 immunoglobulin domain transcripts with predominance of the longer species. Tumor necrosis factor-stimulated melanoma cells bound more VLA·4-expressing cells (melanoma and monocytes) than resting tumor cells and anti-VCAM-1 monoclonal antibodies significantly inhibited binding, thus suggesting that surface VCAM-1 on melanoma is functional. Analysis of melanoma tissue sections demonstrated that VCAM-1 is not a marker of transformation of melanocytes because it can be detected in benign nevi. Although, unlike ICAM-1, VCAM-1 is not correlated with tumor progression, its expression in a fraction of primary Melanomas indicates that it may play a role in regulating host immune response and homotypic interactions in some malignant melanomas.
|Number of pages||8|
|Journal||American Journal of Pathology|
|Publication status||Published - Dec 1992|
ASJC Scopus subject areas
- Pathology and Forensic Medicine