CD74 and neoplasm: To evaluate whether the tumor growth of MDA-MB-231 cells is regulated by CD74 in vivo, MDA-MB-231 pLT-shCD74 #1 and MDA-MB-231 pLT-shCD74 #2 cells and their corresponding control cells, MDA-MB-231 pLT-shCTRL, were injected into the mammary fat pads of athymic mice.