Enhanced PD-L1 Expression in LMP1-positive Cells of Epstein-Barr Virus-associated Malignant Lymphomas and Lymphoproliferative Disorders: A Single-cell Resolution Analysis With Multiplex Fluorescence Immunohistochemistry and In Situ Hybridization.

Epstein-Barr virus (EBV) is associated with various types of human malignancies and with programmed death ligand (PD-L) 1 expression in neoplastic cells. However, in EBV-associated malignant lymphomas and lymphoproliferative disorders (LPDs), there is limited information regarding PD-L1 expression profiles among different histologic types and patterns of EBV latency. First, we investigated PD-L1 and EBV latent gene expression using conventional immunohistochemistry and in situ hybridization in 42 EBV-associated malignant lymphomas and LPDs. Classic Hodgkin lymphoma showed the highest PD-L1 expression with diffuse expression in all cases, followed by diffuse large B-cell lymphoma/Burkitt lymphoma, LPDs, and extranodal NK/T-cell lymphoma. EBV latency at the case level was not associated with PD-L1 expression. We further evaluated the expression of PD-L1 and EBV latent genes in tumor cells at single-cell resolution using multiplex fluorescence imaging. This analysis revealed that positivity rates of latent membrane protein (LMP) 1 in tumor cells were 1.0% to 89.5% (mean 35.4%) in latency type II/III cases, and LMP1 + cells showed more frequent PD-L1 expression than LMP1 - cells ( P <0.0001, paired t test). In contrast, no association was observed between EBV nuclear antigen 2 and PD-L1 expression. Notably, tumor cells exhibiting Hodgkin/Reed-Sternberg cell-like morphology co-expressed PD-L1 and LMP1 more often than those that do not. Our observations suggested that LMP1 upregulates PD-L1 expression and is a potential biomarker for predicting the efficacy of immune checkpoint inhibitors. In addition, the heterogeneous expression of PD-L1 and EBV latent genes may produce diverse tumor cells with different oncogenic and immune-evasive properties, leading to resistance to targeted therapies.

Kume A ，Shinozaki-Ushiku A ，Kunita A ，Kondo A ，Ushiku T ... -  《-》

Clinicopathological evaluation of the programmed cell death 1 (PD1)/programmed cell death-ligand 1 (PD-L1) axis in post-transplant lymphoproliferative disorders: association with Epstein-Barr virus, PD-L1 copy number alterations, and outcome.

The clinical implications of the programmed cell death 1 (PD1)/programmed cell death-ligand 1 (PD-L1) axis in patients with post-transplant lymphoproliferative disorders are largely unknown, and its association with Epstein-Barr virus (EBV) status and PD-L1 copy number alterations (CNAs) has not been thoroughly studied. PD1/PD-L1 expression was studied in 50 adult post-transplant lymphoproliferative disorders, and the correlations with PD-L1 CNAs, EBV, clinicopathological features and outcome were evaluated. Thirty-seven (74%) cases were classified as diffuse large B-cell lymphoma (DLBCL), nine (18%) cases were classified as polymorphic, and four (8%) cases were classified as classic Hodgkin lymphoma. Thirty-four cases were EBV-positive, with 29 of 34 (85%) having latency II or III, and 15 of 34 (44%) having viral replication. PD-L1 expression in tumour cells and tumour-associated macrophages was observed in 30 (60%) and 37 (74%) cases, respectively. PD1 positivity was seen in 16 (32%) cases. PD-L1 expression was associated with EBV with latency II or III (P = 0.001) and organ rejection (P = 0.04), and, in DLBCL, with non-germinal centre type DLBCL (P < 0.001). Cases with PD-L1-positive tumour cells showed a higher number of PD-L1 CNAs than PD-L1-negative cases (P = 0.001). Patients with EBV/latency III/replication and simultaneous PD-L1 expression showed the worst overall survival (P < 0.001). The PD1/PD-L1 axis is deregulated in post-transplant lymphoproliferative disorders, with frequent PD-L1 expression and PD1 negativity. PD-L1 expression is associated with EBV latency II or III and PD-L1 CNAs, and probably reflects a proinflammatory tumour microenvironment. The combined analysis of EBV status and PD-L1 expression may help to identify deeply immunosuppressed patients who can benefit from immune reconstitution approaches.

Veloza L ，Teixido C ，Castrejon N ，Climent F ，Carrió A ，Marginet M ，Soldini D ，González-Farré B ，Ribera-Cortada I ，Lopez-Guillermo A ，González-Barca E ，Sierra A ，Herrera M ，Gómez C ，Garcia A ，Balagué O ，Campo E ，Martinez A ... -  《-》

Epstein-Barr virus latency patterns in polymorphic lymphoproliferative disorders and lymphomas in immunodeficiency settings: Diagnostic implications.

Epstein-Barr virus (EBV) is responsible for many B cell lymphoproliferative disorders (LPD) spanning subclinical infection to immunodeficiency-related neoplasms. EBV establishes a latent infection in the host B cell as defined histologically by the expression of EBV latent membrane proteins and nuclear antigens. Herein, we characterize the latency patterns of immunodeficiency-related neoplasms including post-transplant lymphoproliferative disorders (PTLD) and therapy-related LPD (formerly iatrogenic) with latent membrane protein-1 (LMP-1) and EBV nuclear antigen-2 (EBNA-2) immunohistochemistry. The latency pattern was correlated with immunodeficiency and dysregulation (IDD) status and time from transplant procedure. 38 cases of EBV+ PTLD in comparison to 27 cases of classic Hodgkin lymphoma (CHL) and diffuse large B cell lymphoma (DLBCL) arising in either the therapy-related immunodeficiency setting (n = 12) or without an identified immunodeficiency (n = 15) were evaluated for EBV-encoded small RNAs by in situ hybridization (EBER-ISH) and for LMP-1 and EBNA-2 by immunohistochemistry. A full spectrum of EBV latency patterns was observed across PTLD in contrast to CHL and DLBCL arising in the therapy-related immunodeficiency setting. Polymorphic-PTLD (12 of 16 cases, 75 %) and DLBCL-PTLD (9 of 11 cases, 82 %) showed the greatest proportion of cases with latency III pattern. Whereas, EBV+ CHL in an immunocompetent patient showed exclusively latency II pattern (13 of 13 cases, 100 %). The majority of EBV+ PTLD occurred by three years of transplant procedure date and were enriched for latency III pattern (21 of 22 cases, 95 %). Immunohistochemical identification of EBV latency by LMP-1 and EBNA-2 can help classify PTLD in comparison to other EBV+ B cell LPD and lymphomas arising in therapy-related immunodeficiency and non-immunodeficiency settings.

Volaric AK ，Saleem A ，Younes SF ，Zhao S ，Natkunam Y ... -  《-》

Frequent structural variations involving programmed death ligands in Epstein-Barr virus-associated lymphomas.

Kataoka K ，Miyoshi H ，Sakata S ，Dobashi A ，Couronné L ，Kogure Y ，Sato Y ，Nishida K ，Gion Y ，Shiraishi Y ，Tanaka H ，Chiba K ，Watatani Y ，Kakiuchi N ，Shiozawa Y ，Yoshizato T ，Yoshida K ，Makishima H ，Sanada M ，Onozawa M ，Teshima T ，Yoshiki Y ，Ishida T ，Suzuki K ，Shimada K ，Tomita A ，Kato M ，Ota Y ，Izutsu K ，Demachi-Okamura A ，Akatsuka Y ，Miyano S ，Yoshino T ，Gaulard P ，Hermine O ，Takeuchi K ，Ohshima K ，Ogawa S ... -  《-》

Epstein-Barr virus-encoded EBNA2 alters immune checkpoint PD-L1 expression by downregulating miR-34a in B-cell lymphomas.

Anastasiadou E ，Stroopinsky D ，Alimperti S ，Jiao AL ，Pyzer AR ，Cippitelli C ，Pepe G ，Severa M ，Rosenblatt J ，Etna MP ，Rieger S ，Kempkes B ，Coccia EM ，Sui SJH ，Chen CS ，Uccini S ，Avigan D ，Faggioni A ，Trivedi P ，Slack FJ ... -  《-》