Classical Hodgkin Lymphoma with Reduced ß2M/MHC Class I Expression Is Associated with Inferior Outcome Independent of 9p24.1 Status. Cancer immunology research Roemer, M. G., Advani, R. H., Redd, R. A., Pinkus, G. S., Natkunam, Y., Ligon, A. H., Connelly, C. F., Pak, C. J., Carey, C. D., Daadi, S. E., Chapuy, B., De Jong, D., Hoppe, R. T., Neuberg, D. S., Shipp, M. A., Rodig, S. J. 2016; 4 (11): 910-916

Abstract

In classical Hodgkin lymphoma (cHL), malignant Hodgkin Reed-Sternberg (HRS) cells evade antitumor immunity by multiple mechanisms, including perturbed antigen presentation and enhanced PD-1 signaling. HRS cell expression of the PD-1 ligands is attributable, in part, to copy number alterations of 9p24.1/CD274(PD-L1)/PDCD1LG2(PD-L2) Amplification of PD-L1/PD-L2 is associated with advanced clinical stage and inferior progression-free survival (PFS) following first-line (induction) therapy. The relationships between altered expression of ß2-microglobulin (ß2M), MHC class I, and MHC class II by HRS cells, PD-L1/PD-L2 amplification, and clinical outcome in cHL are poorly defined. We assessed these variables in diagnostic biopsy specimens from 108 patients with cHL who received uniform treatment and had long-term follow-up and found decreased/absent expression of ß2M/MHC class I in 79% (85/108) and decreased/absent expression of MHC class II in 67% (72/108) of cases. Patients with decreased/absent ß2M/MHC class I had shorter PFS, independent of PD-L1/PD-L2 amplification and advanced stage. Decreased or absent MHC class II was unrelated to outcome. These results suggest that MHC class I-mediated antigen presentation by HRS cells is an important component of the biological response to standard chemo/radiotherapy. The paucity of ß2M/MHC class I expression on HRS cells also prompts speculation regarding alternative mechanisms of action of PD-1 blockade in cHL. Cancer Immunol Res; 4(11); 910-6. ©2016 AACR.

View details for PubMedID 27737878