EXPRESSION OF ADHESION RECEPTORS IN EPIDERMAL TUMORS - CORRELATION WITH TNF-ALPHA EXPRESSING CELLS

The expression of intercellular adhesion molecule-1 (ICAM-1), endothelial leukocyte adhesion molecule-1 (E- selectin) and vascular cell adhesion molecule-1 (VCAM-1) was investigated in a series of basal cell carcinomas and squamous cell carcinomas in comparison of benign viral-induced lesions (cutaneous warts, condyloma) and was correlated to the infiltration density and the presence of TNF alpha expressing cells. Tumor cells expressing ICAM-1 were frequently detected in squamous cell carcinoma and condyloma and were correlated with a dense infiltration of HLA-DR and LFA-1 positive cells. Tumor cells were devoid of ICAM-1 in other lesions. Tumor microvessels detected by Von Willebrand factor were consistently present but vessels expressing adhesion receptors were less frequent. E-selectin was usually intense and frequent, whereas VCAM-1 was rare except in dense infiltrated zones and in viral-induced lesions. In all samples, tumor cells strongly expressed TNF alpha. Though the cytotoxin has been reported to be an inducer of adhesion receptors, its expression in epidermal tumors did not correlate with a concomitant up-regulation of epithelial ICAM-1 or endothelial VCAM-1. This may contribute to a reduced influx of T cells into the tumors.