CD74 and mantle cell lymphoma: The most clinically relevant aspects of these findings are: 1) we were able to significantly increase the level of a “druggable” target (CD74) using an active anti-MCL agent (FTY720), generating more CD74 available for milatuzumab binding, and 2) because of the FTY720 effect on CD74 expression, we were able to significantly decrease the dose of these two agents without affecting the synergistic effect on MCL cell viability, suggesting that lower dosages may be used in vivo resulting in a more favorable toxicity profile.