Advertisement

Pervasive mutations of JAK-STAT pathway genes in classical Hodgkin lymphoma

Enrico Tiacci, Erik Ladewig, Gianluca Schiavoni, Alex Penson, Elisabetta Fortini, Valentina Pettirossi, Yuchun Wang, Ariele Rosseto, Alessandra Venanzi, Sofija Vlasevska, Roberta Pacini, Simonetta Piattoni, Alessia Tabarrini, Alessandra Pucciarini, Barbara Bigerna, Alessia Santi, Alessandro M. Gianni, Simonetta Viviani, Antonello Cabras, Stefano Ascani, Barbara Crescenzi, Cristina Mecucci, Laura Pasqualucci, Raul Rabadan and Brunangelo Falini

Key points

  • Identification of genes frequently mutated in cHL fostering tumor growth in a manner amenable to pharmacological targeting

  • Mutated genes include the almost ubiquitous targeting of JAK-STAT pathway members, as well as GNA13, XPO1 and ITPKB

Abstract

Dissecting the pathogenesis of classical Hodgkin lymphoma (cHL), a common cancer in young adults, remains challenging due to the rarity of tumor cells in involved tissues (usually <5%). Here, we analyzed the coding genome of cHL by microdissecting tumor and normal cells from 34 patient biopsies, for a total of ~50,000 singly isolated lymphoma cells. We uncovered several recurrently mutated genes, namely STAT6 (32% of cases), GNA13 (24%), XPO1 (18%) and ITPKB (16%), and document the functional role of mutant STAT6 in sustaining tumor cell viability. Mutations of STAT6 genetically and functionally cooperated with disruption of SOCS1, a JAK-STAT pathway inhibitor, to promote cHL growth. Overall, 87% of cases showed dysregulation of the JAK-STAT pathway by genetic alterations in multiple genes (also including STAT3, STAT5B, JAK1, JAK2, PTPN1), attesting to the pivotal role of this pathway in cHL pathogenesis, and highlighting its potential as new therapeutic target in this disease.

  • Submitted November 6, 2017.
  • Accepted April 5, 2018.