JAK2 rearrangements, including the novel SEC31A-JAK2 fusion, are recurrent in classical Hodgkin lymphoma

• Published in: Blood Vol. 117; no. 15; pp. 4056 - 4064
• Main Authors: Van Roosbroeck, Katrien, Cox, Luk, Tousseyn, Thomas, Lahortiga, Idoya, Gielen, Olga, Cauwelier, Barbara, De Paepe, Pascale, Verhoef, Gregor, Marynen, Peter, Vandenberghe, Peter, De Wolf-Peeters, Chris, Cools, Jan, Wlodarska, Iwona
• Format: Journal Article
• Language: English
• Published: Washington, DC Elsevier Inc 14-04-2011; Americain Society of Hematology
• Subjects: Adult; Aged, 80 and over; Animals; Biological and medical sciences; Bone Marrow Transplantation; Chromosomes, Human, Pair 4; Chromosomes, Human, Pair 9; Disease Models, Animal; Female; Gene Rearrangement - genetics; Genetic Predisposition to Disease - epidemiology; HEK293 Cells; Hematologic and hematopoietic diseases; Hodgkin Disease - epidemiology; Hodgkin Disease - genetics; Humans; Janus Kinase 2 - genetics; Leukemias. Malignant lymphomas. Malignant reticulosis. Myelofibrosis; Male; Medical sciences; Mice; Middle Aged; Oncogene Proteins, Fusion - genetics; Precursor Cell Lymphoblastic Leukemia-Lymphoma - genetics; Prevalence; Protein-Tyrosine Kinases - metabolism; Translocation, Genetic; Vesicular Transport Proteins - genetics; Young Adult; Relapse; Hematology; Enzyme; JAK2 protein tyrosine kinase; Lymphoproliferative syndrome; Transferases; Gene rearrangement; Hodgkin disease; Malignant hemopathy; Lymphoma; Protein-tyrosine kinase; Cancer
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2010-06-291310

The genetics of classical Hodgkin lymphoma (cHL) is poorly understood. The finding of a JAK2-involving t(4;9)(q21;p24) in 1 case of cHL prompted us to characterize this translocation on a molecular level and to determine the prevalence of JAK2 rearrangements in cHL. We showed that the t(4;9)(q21;p24) leads to a novel SEC31A-JAK2 fusion. Screening of 131 cHL cases identified 1 additional case with SEC31A-JAK2 and 2 additional cases with rearrangements involving JAK2. We demonstrated that SEC31A-JAK2 is oncogenic in vitro and acts as a constitutively activated tyrosine kinase that is sensitive to JAK inhibitors. In vivo, SEC31A-JAK2 was found to induce a T-lymphoblastic lymphoma or myeloid phenotype in a murine bone marrow transplantation model. Altogether, we identified SEC31A-JAK2 as a chromosomal aberration characteristic for cHL and provide evidence that JAK2 rearrangements occur in a minority of cHL cases. Given the proven oncogenic potential of this novel fusion, our studies provide new insights into the pathogenesis of cHL and indicate that in at least some cases, constitutive activation of the JAK/STAT pathway is caused by JAK2 rearrangements. The finding that SEC31A-JAK2 responds to JAK inhibitors indicates that patients with cHL and JAK2 rearrangements may benefit from targeted therapies.