ADHESION MOLECULES IN THE DISSEMINATION OF NON-HODGKINS-LYMPHOMAS

Most non-Hodgkin's lymphomas (NHLs) express a number of different adhe sion receptors. A large body of evidence indicates that these adhesion receptors not only regulate normal lymphocyte trafficking but also pl ay a pivotal role in the dissemination of NHL. Thus, cutaneous lymphoc yte antigen, alpha(4) beta(7), alpha(E) beta(7), and L-selectin, which mediate the tissue-specific positioning of normal lymphocytes in the skin, mucosa, epithelium and lymph nodes, respectively, are selectivel y expressed on lymphomas localized at these sites. Furthermore, expres sion of CD44, a family of adhesion receptors with pleiotropic effects on tumor behavior, is related to lymphoma aggressiveness and dissemina tion. Taken together, these findings offer a framework for the underst anding of tumor dissemination in NHL. In view of the similarities betw een lymphocyte behavior and the metastatic behavior of solid tumors, t hese insights might contribute to the understanding of the basic mecha nisms underlying tumor metastasis in non-lymphoid tumors.