To identify predisposition loci for classical Hodgkin Lymphoma (cHL) we conducted a genome-wide association study of 589 cHL cases and 5,199 controls with validation in 4 independent samples totaling 2,057 cases and 3,416 controls. We identified three new susceptibility loci at 2p16.1 (rs1432295, REL; odds ratio [OR]=1.22, Pcombined=1.91×10−8), 8q24.21 (rs2019960, PVT1; OR=1.33, Pcombined=1.26×10−13) and 10p14 (rs501764, GATA3; OR=1.25, Pcombined=7.05×10−8). Furthermore, we confirmed the role of the MHC in disease etiology by revealing a strong HLA association (rs6903608; OR=1.70, Pcombined=2.84×10−50). These data provide new insight into the pathogenesis of cHL.

Purpose: In Hodgkin's lymphoma, constitutive activation of NF-κB promotes tumor cell survival and proliferation. The molecular chaperone heat shock protein 90 (HSP90) has immune regulatory activity and supports the activation of NF-κB in Hodgkin's lymphoma cells. Experimental Design: We analyzed the effect of HSP90 inhibition on viability and NF-κB activity in Hodgkin's lymphoma cells and the consequences for their recognition and killing through natural killer (NK) cells. Results: The novel orally administrable HSP90 inhibitor BIIB021 (CNF2024) inhibited Hodgkin's lymphoma cell viability at low nanomolar concentrations in synergy with doxorubicin and gemcitabine. Annexin V/7-aminoactinomycin D binding assay revealed that BIIB021 selectively induced cell death in Hodgkin's lymphoma cells but not in lymphocytes from healthy individuals. We observed that BIIB021 inhibited the constitutive activity of NF-κB and this was independent of IκB mutations. Furthermore, we analyzed the effect of HSP90 inhibition on NK cell-mediated cytotoxicity. BIIB021 induced the expression of ligands for the activating NK cell receptor NKG2D on Hodgkin's lymphoma cells resulting in an increased susceptibility to NK cell-mediated killing. In a xenograft model of Hodgkin's lymphoma, HSP90 inhibition significantly delayed tumor growth. Conclusions: HSP90 inhibition has direct antitumor activity in Hodgkin's lymphoma in vitro and in vivo. Moreover, HSP90 inhibition may sensitize Hodgkin's lymphoma cells for NK cell-mediated killing via up-regulation of ligands engaging activating NK cell receptors. (Clin Cancer Res 2009;15(16):5108-16) The ubiquitously expressed molecular chaperone heat shock protein 90 (HSP90) promotes tumor cell survival and proliferation by maintaining conformation, stability, and activity of several key oncogenic client proteins (1). Formation of HSP90 cochaperone complexes is essential for the function of HSP90 and requires ATP hydrolysis by a NH 2 -terminal ATPase.

5F11, a fully human monoclonal antibody directed against CD30, effectively induces killing of CD30-expressing lymphoma cell lines in vitro and in animal models. A recently conducted phase 1/2 study shows that 5F11 is well tolerated in heavily pretreated patients with relapsed and refractory CD30 ؉ lymphoma and has some clinical activity. In the present study, we demonstrate that 5F11 activates nuclear factor B (NF-B) and the anti-