Mantle cell lymphomas acquire increased expression of CCL4, CCL5 and 4-1BB-L implicated in cell survival

We have analyzed mantle cell lymphomas (MCLs), using highdensity DNA microarrays, and confirmed the expression of differentially regulated antigens, using flow cytometry and immunohistochemistry. The results show that MCLs acquire expression of molecules that normally are involved in interaction with other immune cells and, thus, might affect the ability of the tumor to survive. The MCL signature is represented by the overexpression of the chemokine CCL4 (MIP-1 beta), implicated in the recruitment of regulatory T cells, as well as CCL5 and 4-1BB-L. The latter molecules are normally involved in chemotaxis of T cells and B cell activation, respectively. Signaling through 4-1BB-L allows B cells to proliferate and the expression of its ligand, by the intra-tumoral mesh of follicular dendritic cells (FDC), could thus serve as a paracrine loop facilitating growth and survival of MCL cells. (c) 2005 Wiley-Liss, Inc.