PD-L1 and PD1 Expression in Lymphomas

摘要: Background Binding of PD-1 with ligands (e.g. PD-L1) expressed on tumor cells or native antigen-presenting results in down-regulation effector T cell function and represents a potent mechanism immune evasion across number solid tumors lymphomas especially classical Hodgkin lymphoma (CHL) aggressive virus-associated B-cell lymphomas. Several biomarkers (different antibodies, gene amplifications mutations) are being investigated for identifying patients who may benefit from checkpoint blockade therapies. It is well known that which strongly express PD-L1 have high clinical response rate to PD1 blockade. We aimed at the expression diverse group There several antibodies used detect expression, however concordance between these not known. previously tested 2 anti-PD-L1 histiocytoses [1], but data lacking. In current study, we measured biopsy samples using 3 identify if there was patterns various subtypes lymphomas. Methods Formalin fixed paraffin embedded tissues 37 B- T-cell lineages (both EBV-positive negative) were (MRQ-22 antibody) (MAB1561, SP142 SP263) automated immunohistochemical methods. Expression 5% more considered positive. Results Neoplastic identified 13/37 cases (35% all cases). The strongest (3+/>50% cells) consistent (4/4 cases) observed RS CHL (2/2 nodular sclerosis 2/2 lymphocyte depleted). Other lineage positive included diffuse large (5/9 DLBCL) lymphomatoid granulomatosis (1/1 LYG). Small lymphocytic (n=3), splenic marginal zone (n=2) follicular (n=8) negative. One four mantle (MCL) borderline (5% positive. NK/T-cell (>50% positive; peripheral (PTCL) one lymphoblastic both EBV- (2/4) negative (2/3) malignancies. Concordance any varied 86 97% (Table 1) Abs agreeing 82%. malignant (2 PTCL 1 DLBCL); reactive PD-1+ T-lymphocytes absent LD variably present other lymphomas. Conclusions Over-expression PD-L1was detected classic HD, B lymphoma, NK/T granulomatosis. A detection three indicates little need companion diagnostic kits, correlation responses level PDL1 should be established future trials. | Antibodies (n) | MAB1561 SP263 | | -------------- ----------- (23) -- 20/23 (86%) (37) 34/35 (97%) (35) 19/22 | Table 1. Concordance antibodies. References: 1. Gatalica, Z., et al., Disseminated beyond BRAFV600E: frequent PD-L1. Oncotarget, 2015. Disclosures Gatalica: Caris Life Sciences: Employment. Arguello: Employment, Equity Ownership. Reddy: Ghosh: Celgene: Membership an entity's Board Directors advisory committees, Speakers Bureau; Pharmacyclics: Bureau.