In vitro and in vivo antitumor activity of the NF-kappaB inhibitor DHMEQ in the human T-cell leukemia virus type I-infected cell line, HUT-102.

Adult T-cell leukemia (ATL) is an aggressive neoplasm caused by human T-cell leukemia virus type I (HTLV-I). The NF-kappaB pathway is activated in ATL cells and in virus-infected cells, and plays a central role in oncogenesis. We examined the effect of the novel NF-kappaB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), on a well-characterized HTLV-I-infected cell line, HUT-102, in vitro and in vivo. DHMEQ inhibited translocation of NF-kappaB p65 to the nucleus and induced apoptotic cell death in vitro. In vivo, DHMEQ inhibited the growth and infiltration of HUT-102 tumor cells transplanted subcutaneously in SCID mice lacking natural killer cell activity.