Atypical Phenotypes in Classical Hodgkin Lymphoma

Usefulness of BATF3 Immunohistochemistry in Diagnosing Classical Hodgkin Lymphoma

It is well recognized that the AP-1 transcription factor BATF3 is constitutively expressed in Hodgkin/Reed-Sternberg (HRS) cells, but its potential as a diagnostic marker for classical Hodgkin lymphoma (cHL) has not yet been addressed. In this study, we performed immunohistochemistry and analyzed the BATF3 expression in lymphoma cells on 218 lymphoma samples belonging to 14 different lymphoma entities. We observed varying degrees of BATF3 expression in nearly half of the cases (n = 100) with BATF3 expression being a constitutive feature of cHL (n = 53) and anaplastic large cell lymphoma (ALCL). By scoring BATF3 expression (BATF3-score) we observed constitutively high BATF3-scores in cHL and ALCL and low to moderate BATF3-scores in all other entities examined. Western blot analysis confirmed BATF3 protein expression in cell lysates from cHL cell lines (n = 7). Thus, BATF3 can be considered a useful IHC marker for the diagnosis of cHL as it is highly sensitive and sufficiently specific when analyzed by BATF3-scoring.

Identification of key genes and pathways associated with classical Hodgkin lymphoma by bioinformatics analysis

The current study aimed to explore the mechanisms associated with classic Hodgkin lymphoma (cHL) to identify novel diagnostic and therapeutic targets. The GES12453 microarray dataset was downloaded from the Gene Expression Omnibus database; the differentially expressed genes (DEGs) between cHL samples and normal B cell samples by were identified using the limma package. Gene ontology (GO) and pathway enrichment analysis of DEGs gene were performed. Furthermore, construction and analysis of protein-protein interaction (PPI) network was performed, and co-expression modules of DEGs were produced. A total of 450 DEGs were identified, comprising 216 upregulated and 234 downregulated genes in cHL compared with normal B cell samples. The DEGs were enriched in biological processes associated with immune response. The upregulated genes were mainly associated with the pathway of transcriptional misregulation in cancer, while downregulated genes were associated with B cell receptor signaling. PPI network analysis demonstrated that IL6 had the highest connectivity degree. Interleukin-6 (IL6) and signal transducer and activator of transcription 1 (STAT1) were demonstrated to be involved with the response to cytokine GO term in co-expression module 1. Spleen tyrosine kinase (SYK), B-cell linker protein (BLNK), CD79B, phospholipase C γ2 (PLCG2) were enriched in the B cell receptor signaling pathway in module 2. Matrix metallopeptidase 9 (MMP9), protein tyrosine phosphatase receptor type C had the highest connectivity degrees in module 3 and module 4, respectively. The results suggested that DEGs, including IL6, STAT1, MMP9, SYK, BLNK, PLCG2 and CD79B, and the pathways of B cell receptor signaling, Epstein-Barr virus infection and transcriptional misregulation in cancer have strong potential to be useful as targets for diagnosis or treatment of cHL.

A single slide multiplex assay for the evaluation of classical Hodgkin lymphoma

Classical Hodgkin lymphoma can be diagnosed with confidence in the majority of cases, but there is a significant subset that remains a diagnostic challenge. The authors have investigated the utility of a novel hyperplexing technology, MultiOmyx™, which may be applied to stain with >60 antibodies on single tissue sections from formalin-fixed paraffin-embedded tissue as an aid to the diagnosis of classical Hodgkin lymphoma. The multiplexing protocol included CD30, CD15, PAX-5, CD20, CD79a, CD45, BOB.1, OCT-2, and CD3 antibodies. The technology showed a high degree of sensitivity, specificity, and precision. Comparison studies with routine hematoxylin and eosin and immunohistochemical assessment of hematopathology cases in which classical Hodgkin lymphoma was included in the differential diagnosis showed concordance in 54 of 56 cases, with the 2 discordant cases illustrating the potential of this multiplexed immunofluorescence technology to improve on traditional immunohistochemistry for classical Hodgkin lymphoma diagnosis. This technology is practical for routine diagnosis and may be particularly useful in cases in which the sample size is limited, few Hodgkin-like cells are present, or in CD30-positive lymphoma cases with difficult morphology. MultiOmyx may potentially benefit other areas of research and diagnostic pathology.