The success of programmed cell death protein 1 (PD-1)/PD-L1-based immunotherapy highlights the critical role played by PD-L1 in cancer progression and reveals an urgent need to develop new approaches to attenuate PD-L1 function by gaining insight into how its expression is controlled. Anaplastic lymphoma kinase (ALK)-positive anaplastic large-cell lymphoma (ALK+ ALCL) expresses a high level of PD-L1 as a result of the constitutive activation of multiple oncogenic signaling pathways downstream of ALK activity, making it an excellent model in which to define the signaling processes responsible for PD-L1 upregulation in tumor cells. Here, using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 library screening, we sought a comprehensive understanding of the molecular effectors required for PD-L1 regulation in ALK+ ALCL. Indeed, we determined that PD-L1 induction is dependent on the nucleophosmin-ALK oncoprotein activation of STAT3, as well as a signalosome containin..... READ ARTICLE
Blood DOI:10.1182/blood.2019001043
Authors: Jing-Ping Zhang, Zhihui Song, Hong-Bo Wang, Lang Lang, Yuan-Zhong Yang, Wenming Xiao, Daniel E. Webster, Wei Wei, Stefan K. Barta, Marshall E. Kadin, Louis M. Staudt, Masao Nakagawa,Yibin Yang
