Extracellular vesicles from type-2 macrophages increase the survival of chronic lymphocytic leukemia cells ex vivo

The resistance of Chronic Lymphocytic Leukemia (CLL) B-cells to cell death is mainly attributed to interactions within their microenvironment, where they interact with various types of cells. Within this microenvironment, CLL-B-cells produce and bind cytokines, growth factors, and extracellular vesicles (EVs). In the present study, EVs purified from nurse-like cells and M2-polarized THP1 cell (M2-THP1) cultures were added to CLL-B-cells cultures. EVs were rapidly internalized by B-cells, leading to a decrease in apoptosis (P = 0.0162 and 0.0469, respectively) and an increased proliferation (P = 0.0335 and 0.0109). Additionally, they induced an increase in the resistance of CLL-B-cells to Ibrutinib, the Bruton kinase inhibitor in vitro (P = 0.0344). A transcriptomic analysis showed an increase in the expression of anti-apoptotic gene BCL-2 (P = 0.0286) but not MCL-1 and an increase in the expression of proliferation-inducing gene APRIL (P = 0.0286) following treatment with EVs. Meanwhile, an analysis of apoptotic protein markers revealed increased amounts of IGFBP-2 (P = 0.0338), CD40 (P = 0.0338), p53 (P = 0.0219) and BCL-2 (P = 0.0338). Finally, exploration of EVs protein content by mass spectrometry revealed they carry various proteins involved in known oncogenic pathways and the RNAseq analysis of CLL-B-cells treated or not with NLCs EVs show various differentially expressed genes.

International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors

BACKGROUND

Sinonasal neoplasms, whether benign and malignant, pose a significant challenge to clinicians and represent a model area for multidisciplinary collaboration in order to optimize patient care. The International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors (ICSNT) aims to summarize the best available evidence and presents 48 thematic and histopathology-based topics spanning the field.

METHODS

In accordance with prior International Consensus Statement on Allergy and Rhinology documents, ICSNT assigned each topic as an Evidence-Based Review with Recommendations, Evidence-Based Review, and Literature Review based on the level of evidence. An international group of multidisciplinary author teams were assembled for the topic reviews using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses format, and completed sections underwent a thorough and iterative consensus-building process. The final document underwent rigorous synthesis and review prior to publication.

RESULTS

The ICSNT document consists of four major sections: general principles, benign neoplasms and lesions, malignant neoplasms, and quality of life and surveillance. It covers 48 conceptual and/or histopathology-based topics relevant to sinonasal neoplasms and masses. Topics with a high level of evidence provided specific recommendations, while other areas summarized the current state of evidence. A final section highlights research opportunities and future directions, contributing to advancing knowledge and community intervention.

CONCLUSION

As an embodiment of the multidisciplinary and collaborative model of care in sinonasal neoplasms and masses, ICSNT was designed as a comprehensive, international, and multidisciplinary collaborative endeavor. Its primary objective is to summarize the existing evidence in the field of sinonasal neoplasms and masses.

Blood regulator of G protein signalling 1 as a potential prognostic biomarker in surgical nonsmall cell lung cancer patients: Correlation with clinical features and survival

INTRODUCTION

Regulator of G protein signalling 1 (RGS1) closely regulates malignant phenotypes and tumour immunity in several cancers, while its clinical value in nonsmall cell lung cancer (NSCLC) is by far rarely reported. Consequently, this study aimed to explore the linkage of blood RGS1 with clinical features and prognosis in surgical NSCLC patients.

METHODS

Two-hundred and ten surgical NSCLC patients were consecutively enrolled in this study, whose RGS1 in peripheral blood mononuclear cells was determined before treatment via reverse transcriptional-quantitative polymerase chain reaction. Additionally, the blood RGS1 was also collected from 30 healthy controls (HCs).

RESULTS

Blood RGS1 was increased in NSCLC patients compared with HCs (P < 0.001). Elevated blood RGS1 was related to lymph node (LYN) metastasis (P = 0.001), higher tumour-nodes-metastasis (TNM) stage (P = 0.004), neoadjuvant chemotherapy administration (P = 0.044), shortened accumulative disease-free survival (DFS) (P = 0.008) and overall survival (OS) (P = 0.013) in NSCLC patients. A multivariate Cox's regression analysis showed that blood RGS1 high expression could independently reflect shortened DFS (hazard ratio = 1.499, P = 0.023), whereas it could not independently predict OS (P > 0.050). Furthermore, blood RGS1 high expression was associated with shortened OS (P = 0.020) in patients with neoadjuvant therapy and with worse DFS (P = 0.028) and OS (P = 0.026) in patients with adjuvant therapy, while blood RGS1 was not linked with DFS or OS in patients without neoadjuvant or adjuvant therapy (all P > 0.050).

CONCLUSION

Elevated blood RGS1 correlates with LYN metastasis, neoadjuvant chemotherapy administration, worse DFS and OS, which might serve as a useful prognostic biomarker for surgical NSCLC patients.

Function and regulation of RGS family members in solid tumours: a comprehensive review

G protein-coupled receptors (GPCRs) play a key role in regulating the homeostasis of the internal environment and are closely associated with tumour progression as major mediators of cellular signalling. As a diverse and multifunctional group of proteins, the G protein signalling regulator (RGS) family was proven to be involved in the cellular transduction of GPCRs. Growing evidence has revealed dysregulation of RGS proteins as a common phenomenon and highlighted the key roles of these proteins in human cancers. Furthermore, their differential expression may be a potential biomarker for tumour diagnosis, treatment and prognosis. Most importantly, there are few systematic reviews on the functional/mechanistic characteristics and clinical application of RGS family members at present. In this review, we focus on the G-protein signalling regulator (RGS) family, which includes more than 20 family members. We analysed the classification, basic structure, and major functions of the RGS family members. Moreover, we summarize the expression changes of each RGS family member in various human cancers and their important roles in regulating cancer cell proliferation, stem cell maintenance, tumorigenesis and cancer metastasis. On this basis, we outline the molecular signalling pathways in which some RGS family members are involved in tumour progression. Finally, their potential application in the precise diagnosis, prognosis and treatment of different types of cancers and the main possible problems for clinical application at present are discussed. Our review provides a comprehensive understanding of the role and potential mechanisms of RGS in regulating tumour progression. Video Abstract.

Lower PTEN may be associated with CD8+ T cell exhaustion in diffuse large B-cell lymphoma

Initially discovered in chronic viral infection and then extended to tumor, 'T-cell exhaustion' is a broad term describing the response of T cells to chronic antigen stimulation. By definition, whether T-cell exhaustion occurs in diffuse large B-cell lymphoma (DLBCL) remains largely unknown because little has been described. Here, the immune-suppressing checkpoint molecules involved in T-cell exhaustion, including PD-1, PD-L1, TIM-3 and TIGIT, whose expression levels were analyzed in DLBCL, were retrieved from the GEPIA database. Compared with the normal control, CD8A, TNFA, IFNG and GZMA were markedly elevated in DLBCL, indicating that infiltrated CD8+ T cells predominate in DLBCL. Meanwhile, inhibitory immune checkpoints, such as PD-1, PD-L1, TIGIT and TIM-3 were drastically higher in DLBCL. PTEN, WNT2 and DKK3 expression were also appraised. It was revealed that PTEN was lower in DLBCL, without being statistically significant. In contrast with PTEN, DKK3 and WNT2 were shown to be pronouncedly higher in DLBCL relative to the normal control. Prognostically, only TIGIT was found to be associated with overall survival in DLBCL. Collectively, all the data we curetted from the GEPIA and TIMER 2.0 databases explicitly indicate that CD8+ T cell exhaustion took place, which may be linked with lower PTEN in DLBCL. To the best of our knowledge, this is the first bioinformatic report explicitly proposing that CD8+ T cell exhaustion occurs in DLBCL, which may be associated with lower PTEN.

Multidirectional characterization of cellular composition and spatial architecture in human multiple primary lung cancers

Multiple primary lung cancers (MPLCs) pose diagnostic and therapeutic challenges in clinic. Here, we orchestrated the cellular and spatial architecture of MPLCs by combining single-cell RNA-sequencing and spatial transcriptomics. Notably, we identified a previously undescribed sub-population of epithelial cells termed as CLDN2⁺ alveolar type II (AT2) which was specifically enriched in MPLCs. This subtype was observed to possess a relatively stationary state, play a critical role in cellular communication, aggregate spatially in tumor tissues, and dominate the malignant histopathological patterns. The CLDN2 protein expression can help distinguish MPLCs from intrapulmonary metastasis and solitary lung cancer. Moreover, a cell surface receptor-TNFRSF18/GITR was highly expressed in T cells of MPLCs, suggesting TNFRSF18 as one potential immunotherapeutic target in MPLCs. Meanwhile, high inter-lesion heterogeneity was observed in MPLCs. These findings will provide insights into diagnostic biomarkers and therapeutic targets and advance our understanding of the cellular and spatial architecture of MPLCs.

Mutational Profile and Pathological Features of a Case of Interleukin-10 and RGS1-Positive Spindle Cell Variant Diffuse Large B-Cell Lymphoma

Diffuse large B-cell lymphoma with spindle cell morphology is a rare variant. We present the case of a 74-year-old male who initially presented with a right supraclavicular (lymph) node enlargement. Histological analysis showed a proliferation of spindle-shaped cells with narrow cytoplasms. An immunohistochemical panel was used to exclude other tumors, such as melanoma, carcinoma, and sarcoma. The lymphoma was characterized by a cell-of-origin subtype of germinal center B-cell-like (GCB) based on Hans’ classifier (CD10-negative, BCL6-positive, and MUM1-negative); EBER negativity, and the absence of BCL2, BCL6, and MYC rearrangements. Mutational profiling using a custom panel of 168 genes associated with aggressive B-cell lymphomas confirmed mutations in ACTB, ARID1B, DUSP2, DTX1, HLA-B, PTEN, and TNFRSF14. Based on the LymphGen 1.0 classification tool, this case had an ST2 subtype prediction. The immune microenvironment was characterized by moderate infiltration of M2-like tumor-associated macrophages (TMAs) with positivity of CD163, CSF1R, CD85A (LILRB3), and PD-L1; moderate PD-1 positive T cells, and low FOXP3 regulatory T lymphocytes (Tregs). Immunohistochemical expression of PTX3 and TNFRSF14 was absent. Interestingly, the lymphoma cells were positive for HLA-DP-DR, IL-10, and RGS1, which are markers associated with poor prognosis in DLBCL. The patient was treated with R-CHOP therapy, and achieved a metabolically complete response.

Copy Number Alteration and Mutational Profile of High-Grade B-Cell Lymphoma with MYC and BCL2 and/or BCL6 Rearrangements, Diffuse Large B-Cell Lymphoma with MYC-Rearrangement, and Diffuse Large B-Cell Lymphoma with MYC-Cluster Amplification

Diffuse large B-cell lymphoma (DLBCL) with MYC alteration is classified as high-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements (double/triple-hit lymphoma; DHL/THL), DLBCL with MYC rearrangement (single-hit lymphoma; SHL) and DLBCL with MYC-cluster amplification (MCAD). To elucidate the genetic features of DHL/THL, SHL, and MCAD, 23 lymphoma cases from Tokai University Hospital were analyzed. The series included 10 cases of DHL/THL, 10 cases of SHL and 3 cases of MCAD. The analysis used whole-genome copy number microarray analysis (OncoScan) and a custom-made next-generation sequencing (NGS) panel of 115 genes associated with aggressive B-cell lymphomas. The copy number alteration (CNA) profiles were similar between DHL/THL and SHL. MCAD had fewer CNAs than those of DHL/THL and SHL, except for +8q24. The NGS profile characterized DHL/THL with a higher "mutation burden" than SHL (17 vs. 10, p = 0.010), and the most relevant genes for DHL/THL were BCL2 and SOCS1, and for SHL was DTX1. MCAD was characterized by mutations of DDX3X, TCF3, HLA-A, and TP53, whereas MYC was unmutated. In conclusion, DHL/THL, SHL, and MCAD have different profiles.

Clinicopathological analysis of follicular lymphoma with BCL2, BCL6, and MYC rearrangements

Most follicular lymphomas (FL) show t(14;18)/IGH-BCL2 translocation, but rearrangement (R) negative cases exist. A series of 140 FL patients with a BCL2, BCL6, and MYC gene status examined by fluorescence in situ hybridization (FISH) were classified into five groups: (a) BCL2-R group (BCL2-R/BCL6-G/MYC-G) (G, germline), 77 cases; (b) BCL2/BCL6 double-R group (BCL2-R/BCL6-R/MYC-G), 16 cases; (c) BCL6-R group (BCL2-G/BCL6-R/MYC-G), 16 cases; (d) MYC-R group (BCL2-R or G/BCL6-R or G/MYC-R), three cases; (e) Triple-G group (BCL2-G/BCL6-G/MYC-G), 28 cases. The BCL6-R group had different clinicopathological characteristics. It showed lower rates of an advanced clinical stage and bone marrow invasion, less disease progression (p = 0.036), and a 'trend' toward a favorable progression-free survival (PFS) (p = 0.06). It also showed higher rates of grade 3A and MUM1-expression, and when analyzing the interfollicular spread pattern of CD20-positive cells, had fewer cases showing the IF3+ pattern (high interfollicular spread). Moreover, cases with BCL6-R and/or BCL6 gain (with cases of BCL2 rearrangement and/or of copy number gain excluded) correlated with favorable PFS (p = 0.014) and less IF3+ pattern (p = 0.007). We demonstrated that BCL6-R FLs showed unique clinicopathological findings, and FISH of BCL2, BCL6, and MYC is useful for FL diagnosis and clinical management.

PARK2 regulates eIF4B-driven lymphomagenesis

Patients with high-risk diffuse large B-cell lymphoma (DLBCL) have poor outcomes following first-line cyclophosphamide, doxorubicin, vincristine, prednisone, and rituximab (R-CHOP); thus, treatment of this fatal disease remains an area of unmet medical need and requires identification of novel therapeutic approaches. Dysregulation of protein translation initiation has emerged as a common downstream node in several malignancies, including lymphoma. Ubiquitination, a prominent post-translational modification associated with substrate degradation, has recently been shown to be a key modulator of nascent peptide synthesis by limiting several translational initiation factors. While a few deubiquitinases have been identified, the E3-ligase responsible for the critical ubiquitination of these translational initiation factors is still unknown. In this study, using complementary cellular models along with clinical readouts, we establish that PARK2 ubiquitinates eIF4B and consequently regulates overall protein translational activity. The formation of this interaction depends on upstream signaling, which is negatively regulated at the protein level of PARK2. Through biochemical, mutational, and genetic studies, we identified PARK2 as a mTORC1 substrate. mTORC1 phosphorylates PARK2 at Ser127, which blocks its cellular ubiquitination activity, thereby hindering its tumor suppressor effect on eIF4B's stability. This resultant increase of eIF4B protein level helps drive enhanced overall protein translation. These data support a novel paradigm in which PARK2-generated eIF4B ubiquitination serves as an anti-oncogenic intracellular inhibitor of protein translation, attenuated by mTORC1 signaling. Implications: Our data implicates the FASN/mTOR-PARK2-eIF4B axis as a critical driver of enhanced oncogene expression contributing to lymphomagenesis.

Artificial Intelligence Analysis of Gene Expression Predicted the Overall Survival of Mantle Cell Lymphoma and a Large Pan-Cancer Series

Mantle cell lymphoma (MCL) is a subtype of mature B-cell non-Hodgkin lymphoma characterized by a poor prognosis. First, we analyzed a series of 123 cases (GSE93291). An algorithm using multilayer perceptron artificial neural network, radial basis function, gene set enrichment analysis (GSEA), and conventional statistics, correlated 20,862 genes with 28 MCL prognostic genes for dimensionality reduction, to predict the patients' overall survival and highlight new markers. As a result, 58 genes predicted survival with high accuracy (area under the curve = 0.9). Further reduction identified 10 genes: KIF18A, YBX3, PEMT, GCNA, and POGLUT3 that associated with a poor survival; and SELENOP, AMOTL2, IGFBP7, KCTD12, and ADGRG2 with a favorable survival. Correlation with the proliferation index (Ki67) was also made. Interestingly, these genes, which were related to cell cycle, apoptosis, and metabolism, also predicted the survival of diffuse large B-cell lymphoma (GSE10846, n = 414), and a pan-cancer series of The Cancer Genome Atlas (TCGA, n = 7289), which included the most relevant cancers (lung, breast, colorectal, prostate, stomach, liver, etcetera). Secondly, survival was predicted using 10 oncology panels (transcriptome, cancer progression and pathways, metabolic pathways, immuno-oncology, and host response), and TYMS was highlighted. Finally, using machine learning, C5 tree and Bayesian network had the highest accuracy for prediction and correlation with the LLMPP MCL35 proliferation assay and RGS1 was made. In conclusion, artificial intelligence analysis predicted the overall survival of MCL with high accuracy, and highlighted genes that predicted the survival of a large pan-cancer series.

Single-Cell Transcriptome Analysis Reveals RGS1 as a New Marker and Promoting Factor for T-Cell Exhaustion in Multiple Cancers

T-cell exhaustion is one of the main reasons of tumor immune escape. Using single-cell transcriptome data of CD8+ T cells in multiple cancers, we identified different cell types, in which Pre_exhaust and exhausted T cells participated in negative regulation of immune system process. By analyzing the coexpression network patterns and differentially expressed genes of Pre_exhaust, exhausted, and effector T cells, we identified 35 genes related to T-cell exhaustion, whose high GSVA scores were associated with significantly poor prognosis in various cancers. In the differentially expressed genes, RGS1 showed the greatest fold change in Pre_exhaust and exhausted cells of three cancers compared with effector T cells, and high expression of RGS1 was also associated with poor prognosis in various cancers. Additionally, RGS1 protein was upregulated significantly in tumor tissues in the immunohistochemistry verification. Furthermore, RGS1 displayed positive correlation with the 35 genes, especially highly correlated with PDCD1, CTLA4, HAVCR2, and TNFRSF9 in CD8+ T cells and cancer tissues, indicating the important roles of RGS1 in CD8+ T-cell exhaustion. Considering the GTP-hydrolysis activity of RGS1 and significantly high mRNA and protein expression in cancer tissues, we speculated that RGS1 potentially mediate the T-cell retention to lead to the persistent antigen stimulation, resulting in T-cell exhaustion. In conclusion, our findings suggest that RGS1 is a new marker and promoting factor for CD8+ T-cell exhaustion and provide theoretical basis for research and immunotherapy of exhausted cells.

High PTX3 expression is associated with a poor prognosis in diffuse large B-cell lymphoma

Tumor‐associated macrophages (TAMs) are associated with a poor prognosis of diffuse large B‐cell lymphoma (DLBCL). As macrophages are heterogeneous, the immune polarization and their pathological role warrant further study. We characterized the microenvironment of DLBCL by immunohistochemistry in a training set of 132 cases, which included 10 Epstein–Barr virus‐encoded small RNA (EBER)‐positive and five high‐grade B‐cell lymphomas, with gene expression profiling in a representative subset of 37 cases. Diffuse large B‐cell lymphoma had a differential infiltration of TAMs. The high infiltration of CD68 (pan‐macrophages), CD16 (M1‐like), CD163, pentraxin 3 (PTX3), and interleukin (IL)‐10‐positive macrophages (M2c‐like) and low infiltration of FOXP3‐positive regulatory T lymphocytes (Tregs) correlated with poor survival. Activated B cell‐like DLBCL was associated with high CD16, CD163, PTX3, and IL‐10, and EBER‐positive DLBCL with high CD163 and PTX3. Programmed cell death‐ligand 1 positively correlated with CD16, CD163, IL‐10, and RGS1. In a multivariate analysis of overall survival, PTX3 and International Prognostic Index were identified as the most relevant variables. The gene expression analysis showed upregulation of genes involved in innate and adaptive immune responses and macrophage and Toll‐like receptor pathways in high PTX3 cases. The prognostic relevance of PTX3 was confirmed in a validation set of 159 cases. Finally, in a series from Europe and North America (GSE10846, R‐CHOP‐like treatment, n = 233) high gene expression of PTX3 correlated with poor survival, and moderately with CSF1R, CD16, MITF, CD163, MYC, and RGS1. Therefore, the high infiltration of M2c‐like immune regulatory macrophages and low infiltration of FOXP3‐positive Tregs is associated with a poor prognosis in DLBCL, for which PTX3 is a new prognostic biomarker.

Whole-genome copy number and immunohistochemical analyses on surgically resected intracholecystic papillary neoplasms

Intracholecystic papillary neoplasms are newly defined precancerous lesions. According to Classification of the World Health Organization, they have four histological morphologies, which are biliary, gastric, intestinal, and oncocytic. This study evaluated 17 patients with resected intracholecystic papillary neoplasms in terms of histological, immunohistochemical, and copy number variation (CNV). The histological subtypes included 5 cases of low-grade (5 gastric) and 12 cases of high-grade (6 gastric and 6 biliary) neoplasms. Most cases showed high expression of MUC1, MUC5AC, and CK7, moderate expression of MUC6 and Ki-67, and low expression of CK20, MUC2, and CDX2. The CNV profile identified gain of 7q in 12%, and loss of 1p (18%), 5q (29%), 9p (35%), 12p (17%), 17p (24%), and 19p (18%). No CNVs were observed in low-grade neoplasms, whereas high-grade ones had increasing abnormalities. β-catenin was often expressed in the nucleus of neoplasms with gastric morphology, suggesting the involvement of the Wnt/β-catenin pathway. However, it was not expressed among those with biliary morphology, which instead exhibited high p53 expression. Neoplasms with biliary morphology showed more CNV changes (9p, 17p, 19p losses). Distinct immunological and CNV patterns were seen in both morphologies, suggesting differences in their pathogenesis. More CNVs accumulated with tumor progression.

Integrative Statistics, Machine Learning and Artificial Intelligence Neural Network Analysis Correlated CSF1R with the Prognosis of Diffuse Large B-Cell Lymphoma

Tumor-associated macrophages (TAMs) of the immune microenvironment play an important role in the Diffuse Large B-cell Lymphoma (DLBCL) pathogenesis. This research aimed to characterize the expression of macrophage colony-stimulating factor 1 receptor (CSF1R) at the gene and protein level in correlation with survival. First, the immunohistochemical expression of CSF1R was analyzed in a series of 198 cases from Tokai University Hospital and two patterns of histological expression were found, a TAMs, and a diffuse B-lymphocytes pattern. The clinicopathological correlations showed that the CSF1R + TAMs pattern associated with a poor progression-free survival of the patients, disease progression, higher MYC proto-oncogene expression, lower MDM2 expression, BCL2 translocation, and a MYD88 L265P mutation. Conversely, a diffuse CSF1R + B-cells pattern was associated with a favorable progression-free survival. Second, the histological expression of CSF1R was also correlated with 10 CSF1R-related markers including CSF1, STAT3, NFKB1, Ki67, MYC, PD-L1, TNFAIP8, IKAROS, CD163, and CD68. CSF1R moderately correlated with STAT3, TNFAIP8, CD68, and CD163 in the cases with the CSF1R + TAMs pattern. In addition, machine learning modeling predicted the CSF1R immunohistochemical expression with high accuracy using regression, generalized linear, an artificial intelligence neural network (multilayer perceptron), and support vector machine (SVM) analyses. Finally, a multilayer perceptron analysis predicted the genes associated with the CSF1R gene expression using the GEO GSE10846 DLBCL series of the Lymphoma/Leukemia Molecular Profiling Project (LLMPP), with correlation to the whole set of 20,683 genes as well as with an immuno-oncology cancer panel of 1790 genes. In addition, CSF1R positively correlated with SIRPA and inversely with CD47. In conclusion, the CSF1R histological pattern correlated with the progression-free survival of the patients of the Tokai series, and predictive analytics is a feasible strategy in DLBCL.

The Incidence of Epstein-Barr Virus-Positive Diffuse Large B-Cell Lymphoma: A Systematic Review and Meta-Analysis

Simple Summary

The worldwide prevalence of Epstein-Barr virus-positive (EBV+) diffuse large B-cell lymphoma (DLBCL) is undetermined. There is no clearly defined cut-off for EBV-encoded RNA (EBER) positivity in tumor cells by in situ hybridization. A lack of common criteria for positive expression of EBER has been raised as a limitation for interpreting and understanding the geographic and ethnic disparity of prevalence of EBV+ DLBCL. We conducted a systematic literature review and meta-analysis to establish the proportions of EBV+ DLBCL patients. Results showed that the pooled proportion of EBER positivity was 7.9% in patients with de novo DLBCL. The prevalence of EBV+ DLBCL was significantly higher in Asia and South America compared with Western countries. A tendency for lower pooled proportions was observed in studies using a higher cut-off for EBER positivity. The patients’ age did not significantly affect the prevalence. These findings may improve our current knowledge of the EBV+ DLBCL.

Abstract

The worldwide prevalence of Epstein-Barr virus-positive (EBV+) diffuse large B-cell lymphoma (DLBCL) is undetermined. There is no clearly defined cut-off for EBV-encoded RNA (EBER) positivity in tumor cells by in-situ hybridization. The purpose of this study was to establish the proportions of EBV+ DLBCL patients and influence of the different cut-offs for EBER positivity, geographical location, and age on the prevalence of EBV+ DLBCL. PubMed and EMBASE were searched for studies published up to May 28, 2020 that reported proportions of EBER positivity in immunocompetent and de novo DLBCL patients. The pooled proportions were computed by an inverse variance method for calculating the weights and the DerSimonian–Laird method. Multiple subgroup analyses were conducted to explore any heterogeneity. Thirty-one studies (8249 patients) were included. The pooled proportion of EBV+ DLBCL was 7.9% (95% CI, 6.2–10.0%) with significant heterogeneity among studies (p < 0.001). The prevalence of EBV+ DLBCL was significantly higher in Asia and South America compared with Western countries (p < 0.01). The cut-offs for EBER positivity (10%, 20%, 50%) and patients’ age (≥50 years vs. <50 years) did not significantly affect the prevalence (p ≥ 0.10). EBV+ DLBCL is rare with a pooled proportion of 7.9% in patients with DLBCL and the geographic heterogeneity was confirmed.

Conditional expression of HGAL leads to the development of diffuse large B-cell lymphoma in mice

Diffuse large B-cell lymphomas (DLBCLs) are clinically and genetically heterogeneous tumors. Deregulation of diverse biological processes specific to B cells, such as B-cell receptor (BCR) signaling and motility regulation, contribute to lymphomagenesis. Human germinal center associated lymphoma (HGAL) is a B-cell-specific adaptor protein controlling BCR signaling and B lymphocyte motility. In normal B cells, it is expressed in germinal center (GC) B lymphocytes and promptly downregulated upon further differentiation. The majority of DLBCL tumors, primarily GC B-cell types, but also activated types, express HGAL. To investigate the consequences of constitutive expression of HGAL in vivo, we generated mice that conditionally express human HGAL at different stages of hematopoietic development using 3 restricted Cre-mediated approaches to initiate expression of HGAL in hematopoietic stem cells, pro-B cells, or GC B cells. Following immune stimulation, we observed larger GCs in mice in which HGAL expression was initiated in GC B cells. All 3 mouse strains developed DLBCL at a frequency of 12% to 30% starting at age 13 months, leading to shorter survival. Immunohistochemical studies showed that all analyzed tumors were of the GC B-cell type. Exon sequencing revealed mutations reported in human DLBCL. Our data demonstrate that constitutive enforced expression of HGAL leads to DLBCL development.

Biliverdin Protects Against Cerebral Ischemia/Reperfusion Injury by Regulating the miR-27a-3p/Rgs1 Axis

BACKGROUND

We have previously demonstrated that biliverdin has neuroprotective effects that ameliorate cerebral ischemia/reperfusion (I/R) injury in rats. However, the underlying mechanism is unknown. This study aimed at elucidating on the modulatory role of miR-27a-3p on Rgs1 as a mechanism by which biliverdin affects cerebral I/R injury.

METHODS

Middle cerebral artery occlusion/reperfusion (MCAO/R) was used to establish I/R rat models while oxygen glucose deprivation/reoxygenation (OGD/R) was used to induce hippocampal neurons to establish I/R models in vitro. Infarct volume was assessed by TTC staining. Apoptotic analyses of ischemic cortical neurons and cells were performed by TUNEL staining and flow cytometry, respectively. Cell viability was assessed by the CCK-8 assay while the target of miR-27a-3p was determined by double luciferase reporter assay. Relative expression levels of miR-27a-3p and Rgs1 (in vivo and in vitro) as well as markers of inflammation and apoptosis (in vitro) were detected by RT-qPCR. Then, Elisa and western blot were used to assess protein expression levels of inflammatory and apoptotic markers in vitro.

RESULTS

Biliverdin suppressed inflammation and apoptosis in hippocampal neurons upon OGD/R, and reduced cerebral infarction volume as well as apoptosis in the MCAO/R rat model. Furthermore, biliverdin upregulated miR-27a-3p and downregulated hippocampal neuron Rgs1 after OGD/R as well as in rat brain tissues after cerebral I/R. Bioinformatic analysis revealed an miR-27a-3p docking site in the 3'-UTR region of Rgs1. Luciferase reporter assays showed that Rgs1 is an miR-27a-3p target. Moreover, miR-27a-3p upregulation inhibited OGD/R-triggered inflammation and suppressed neuronal apoptosis. Rgs1 knockdown suppressed OGD/R-triggered inflammation and decreased neuronal apoptosis while miR-27a-3p downregulation reversed the protective effect of Rgs1 knockdown. Moreover, miR-27a-3p overexpression and Rgs1 silencing suppressed NF-κB (p65) expression.

CONCLUSION

Biliverdin protects against cerebral I/R injury by regulating the miR-27a-3p/Rgs1 axis, thereby inhibiting inflammation and apoptosis.

The landscape of host genetic factors involved in immune response to common viral infections

BACKGROUND

Humans and viruses have co-evolved for millennia resulting in a complex host genetic architecture. Understanding the genetic mechanisms of immune response to viral infection provides insight into disease etiology and therapeutic opportunities.

METHODS

We conducted a comprehensive study including genome-wide and transcriptome-wide association analyses to identify genetic loci associated with immunoglobulin G antibody response to 28 antigens for 16 viruses using serological data from 7924 European ancestry participants in the UK Biobank cohort.

RESULTS

Signals in human leukocyte antigen (HLA) class II region dominated the landscape of viral antibody response, with 40 independent loci and 14 independent classical alleles, 7 of which exhibited pleiotropic effects across viral families. We identified specific amino acid (AA) residues that are associated with seroreactivity, the strongest associations presented in a range of AA positions within DRβ1 at positions 11, 13, 71, and 74 for Epstein-Barr virus (EBV), Varicella zoster virus (VZV), human herpesvirus 7, (HHV7), and Merkel cell polyomavirus (MCV). Genome-wide association analyses discovered 7 novel genetic loci outside the HLA associated with viral antibody response (P < 5.0 × 10-8), including FUT2 (19q13.33) for human polyomavirus BK (BKV), STING1 (5q31.2) for MCV, and CXCR5 (11q23.3) and TBKBP1 (17q21.32) for HHV7. Transcriptome-wide association analyses identified 114 genes associated with response to viral infection, 12 outside of the HLA region, including ECSCR: P = 5.0 × 10-15 (MCV), NTN5: P = 1.1 × 10-9 (BKV), and P2RY13: P = 1.1 × 10-8 EBV nuclear antigen. We also demonstrated pleiotropy between viral response genes and complex diseases, from autoimmune disorders to cancer to neurodegenerative and psychiatric conditions.

CONCLUSIONS

Our study confirms the importance of the HLA region in host response to viral infection and elucidates novel genetic determinants beyond the HLA that contribute to host-virus interaction.

The landscape of host genetic factors involved in immune response to common viral infections

INTRODUCTION

Humans and viruses have co-evolved for millennia resulting in a complex host genetic architecture. Understanding the genetic mechanisms of immune response to viral infection provides insight into disease etiology and therapeutic opportunities.

METHODS

We conducted a comprehensive study including genome-wide and transcriptome-wide association analyses to identify genetic loci associated with immunoglobulin G antibody response to 28 antigens for 16 viruses using serological data from 7924 European ancestry participants in the UK Biobank cohort.

RESULTS

Signals in human leukocyte antigen (HLA) class II region dominated the landscape of viral antibody response, with 40 independent loci and 14 independent classical alleles, 7 of which exhibited pleiotropic effects across viral families. We identified specific amino acid (AA) residues that are associated with seroreactivity, the strongest associations presented in a range of AA positions within DRβ1 at positions 11, 13, 71, and 74 for Epstein-Barr Virus (EBV), Varicella Zoster Virus (VZV), Human Herpes virus 7, (HHV7) and Merkel cell polyomavirus (MCV). Genome-wide association analyses discovered 7 novel genetic loci outside the HLA associated with viral antibody response (P<5.×10-8), including FUT2 (19q13.33) for human polyomavirus BK (BKV), STING1 (5q31.2) for MCV, as well as CXCR5 (11q23.3) and TBKBP1 (17q21.32) for HHV7. Transcriptome-wide association analyses identified 114 genes associated with response to viral infection, 12 outside of the HLA region, including ECSCR: P=5.0×10-15 (MCV), NTN5: P=1.1×10-9 (BKV), and P2RY13: P=1.1×10-8 EBV nuclear antigen. We also demonstrated pleiotropy between viral response genes and complex diseases; from autoimmune disorders to cancer to neurodegenerative and psychiatric conditions.

CONCLUSIONS

Our study confirms the importance of the HLA region in host response to viral infection and elucidates novel genetic determinants beyond the HLA that contribute to host-virus interaction.

Role of ETS1 in the Transcriptional Network of Diffuse Large B Cell Lymphoma of the Activated B Cell-Like Type

Diffuse large B cell lymphoma (DLBCL) is a heterogenous disease that has been distinguished into at least two major molecular entities, the germinal center-like B cell (GCB) DLBCL and activated-like B cell (ABC) DLBCL, based on transcriptome expression profiling. A recurrent ch11q24.3 gain is observed in roughly a fourth of DLBCL cases resulting in the overexpression of two ETS transcription factor family members, ETS1 and FLI1. Here, we knocked down ETS1 expression by siRNA and analyzed expression changes integrating them with ChIP-seq data to identify genes directly regulated by ETS1. ETS1 silencing affected expression of genes involved in B cell signaling activation, B cell differentiation, cell cycle, and immune processes. Integration of RNA-Seq (RNA sequencing) data and ChIP-Seq (chromatin immunoprecipitation sequencing) identified 97 genes as bona fide, positively regulated direct targets of ETS1 in ABC-DLBCL. Among these was the Fc receptor for IgM, FCMR (also known as FAIM3 or Toso), which showed higher expression in ABC- than GCB-DLBCL clinical specimens. These findings show that ETS1 is contributing to the lymphomagenesis in a subset of DLBCL and identifies FCMR as a novel target of ETS1, predominantly expressed in ABC-DLBCL.

TBLR1 and CREBBP as potential novel prognostic immunohistochemical biomarkers in diffuse large B-cell lymphoma

Recent studies have identified prognostic mutational clusters for diffuse large B-cell lymphoma (DLBCL) patients, both within and outside the original cell-of-origin (COO) classification. For many of these mutations, there is limited information regarding the corresponding protein expression. With the aim to determine the relationship of protein expression and intensity to COO and prognosis, we used digital image analysis to quantitate immunohistochemical staining of CREBBP, IRF8, EZH2, and TBLR1 in 209 DLBCL patients. We found that patients with strong nuclear expression of TBLR1 had inferior progression-free survival (PFS) and overall survival (OS) in univariable analysis and inferior PFS in multivariable analysis. Patients with higher proportion of intermediate to strong nuclear CREBBP expression had a worse PFS and OS in univariable analysis. CREBBP was expressed with stronger intensity in non-GCB patients and the prognostic impact was restricted to this subgroup. These findings suggest that high nuclear protein expression of TBLR1 and CREBBP is negatively associated with prognosis in DLBCL.

Dasatinib exacerbates splenomegaly of mice inoculated with Epstein-Barr virus-infected lymphoblastoid cell lines

Latent infection of Epstein-Barr virus (EBV) is associated with a poor prognosis in patients with B cell malignancy. We examined whether dasatinib, a multi kinase inhibitor, which is broadly used for chronic myeloid leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia is effective on EBV-positive B cell malignancies, using lymphoblastoid cell lines (LCLs) in vitro and in vivo. As a result, in vitro experiments showed that dasatinib induced cell death of the EBV-LCLs which was not accompanied with a lytic reactivation of EBVs. To evaluate the effectiveness in EBV latency type III represented by immunodeficiency lymphoma, LCL-inoculated immunodeficient NOD/shi-scid/Il2rg^nul (NOG) mice were treated with dasatinib. However, in vivo experiments revealed that dasatinib treatment exacerbated tumor cell infiltration into the spleen of LCL-inoculated NOG mice, whereas tumor size at the inoculated site was not affected by the treatment. These results suggest that dasatinib exacerbates the pathogenesis at least in some situations although the drug is effective in vitro. Hence, we should carefully examine a possibility of dasatinib repositioning for EBV⁺ B cell malignancies.

OSdlbcl: An online consensus survival analysis web server based on gene expression profiles of diffuse large B-cell lymphoma

Diffuse large B‐cell lymphoma (DLBCL) is the most common subtype of non‐Hodgkin lymphoma (NHL) and is a clinical, pathological, and molecular heterogeneous disease with highly variable clinical outcomes. Currently, valid prognostic biomarkers in DLBCL are still lacking. To optimize targeted therapy and improve the prognosis of DLBCL, the performance of proposed biomarkers needs to be evaluated in multiple cohorts, and new biomarkers need to be investigated in large datasets. Here, we developed a consensus Online Survival analysis web server for Diffuse Large B‐Cell Lymphoma, abbreviated OSdlbcl, to assess the prognostic value of individual gene. To build OSdlbcl, we collected 1100 samples with gene expression profiles and clinical follow‐up information from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. In addition, DNA mutation data were also collected from the TCGA database. Overall survival (OS), progression‐free survival (PFS), disease‐specific survival (DSS), disease‐free interval (DFI), and progression‐free interval (PFI) are important endpoints to reflect the survival rate in OSdlbcl. Moreover, clinical features were integrated into OSdlbcl to allow data stratifications according to the user's special needs. By inputting an official gene symbol and selecting desired criteria, the survival analysis results can be graphically presented by the Kaplan‐Meier (KM) plot with hazard ratio (HR) and log‐rank p value. As a proof‐of‐concept demonstration, the prognostic value of 23 previously reported survival associated biomarkers, such as transcription factors FOXP1 and BCL2, was evaluated in OSdlbcl and found to be significantly associated with survival as reported (HR = 1.73, P < .01; HR = 1.47, P = .03, respectively). In conclusion, OSdlbcl is a new web server that integrates public gene expression, gene mutation data, and clinical follow‐up information to provide prognosis evaluations for biomarker development for DLBCL. The OSdlbcl web server is available at https://bioinfo.henu.edu.cn/DLBCL/DLBCLList.jsp.

An Overview on G Protein-coupled Receptor-induced Signal Transduction in Acute Myeloid Leukemia

BACKGROUND

Acute Myeloid Leukemia (AML) is a genetically heterogeneous disease characterized by uncontrolled proliferation of precursor myeloid-lineage cells in the bone marrow. AML is also characterized by patients with poor long-term survival outcomes due to relapse. Many efforts have been made to understand the biological heterogeneity of AML and the challenges to develop new therapies are therefore enormous. G Protein-coupled Receptors (GPCRs) are a large attractive drug-targeted family of transmembrane proteins, and aberrant GPCR expression and GPCR-mediated signaling have been implicated in leukemogenesis of AML. This review aims to identify the molecular players of GPCR signaling, focusing on the hematopoietic system, which are involved in AML to help developing novel drug targets and therapeutic strategies.

METHODS

We undertook an exhaustive and structured search of bibliographic databases for research focusing on GPCR, GPCR signaling and expression in AML.

RESULTS AND CONCLUSION

Many scientific reports were found with compelling evidence for the involvement of aberrant GPCR expression and perturbed GPCR-mediated signaling in the development of AML. The comprehensive analysis of GPCR in AML provides potential clinical biomarkers for prognostication, disease monitoring and therapeutic guidance. It will also help to provide marker panels for monitoring in AML. We conclude that GPCR-mediated signaling is contributing to leukemogenesis of AML, and postulate that mass spectrometrybased protein profiling of primary AML cells will accelerate the discovery of potential GPCR related biomarkers for AML.

Single-Cell Sequencing Reveals the Relationship between Phenotypes and Genotypes of Klinefelter Syndrome

Klinefelter syndrome (KS) is one of the most common congenital disorders of male infertility. Given its high heterogeneity in clinical and genetic presentation, the relationship between transcriptome, clinical phenotype, and associated co-morbidities seen in KS has not been fully clarified. Here, we report a 47,XXY Chinese male with infertility and analyzed the differences in gene expression patterns of peripheral blood mononuclear cells (PBMCs) with regard to a Chinese male and a female control with normal karyotype by single-cell sequencing. A total of 24,439 cells were analyzed and divided into 5 immune cell types (including B cells, T cells, macrophage cells, dendritic cells, and natural killer cells) according to marker genes. Using unsupervised dimensionality reduction and clustering algorithms, we identified molecularly distinct subpopulations of cells between the KS patient and both controls. Gene ontology enrichment analyses yielded terms associated with well-known comorbidities seen in KS as well as an affected immune system and type I diabetes mellitus. Based on our data, we identified several candidate genes which may be implicated in regulating the phenotype of KS. Overall, this analysis provides a comprehensive map of the cell types of PBMCs in a KS patient at the single-cell level, which will contribute to the prevention of comorbidity and improvement of the life quality of KS patients.

Expression of IL-34 correlates with macrophage infiltration and prognosis of diffuse large B-cell lymphoma

Objectives

Infiltration of macrophages through the tyrosine kinase receptor CSF1R is a poor prognosis factor in various solid tumors. Indeed, these tumors produce CSF1R ligand, macrophage colony‐stimulating factor (M‐CSF) or interleukin‐34 (IL‐34). However, the significance of these cytokines, particularly, the newly discovered IL‐34 in haematological malignancies, is not fully understood. We therefore analysed the role of IL‐34 in diffuse large B‐cell lymphoma (DLBCL), the most common subtype of malignant lymphoma.

Methods

We analysed formalin‐fixed paraffin‐embedded lymphoma tissues of 135 DLBCL patients for the expression of IL‐34 and the number of macrophages, and the survival of these patients. The expression of IL‐34 in DLBCL cell lines and the activity of IL‐34 to induce the migration of monocytic cells were also characterised.

Results

Several lymphoma tissues showed a clear IL‐34 signal, and such signal was detectable in 36% of patients. DLBCL cell lines also expressed IL‐34. Interestingly, the percentage of IL‐34⁺ patients in the activated B‐cell subtype was significantly higher than that in the germinal centre B‐cell subtype. More interestingly, IL‐34⁺ patients showed shorter survival periods and higher number of macrophages in lymphoma tissues. The recruitment of monocytes is likely the first step for the higher macrophage density in the IL‐34⁺ lymphoma tissues. Indeed, IL‐34 induced the migration of monocytic cells.

Conclusion

Our results raise the possibility that IL‐34 in lymphoma tissues of DLBCL patients recruits monocytes, leading to the higher number of macrophages in the tissues and poor prognosis of patients. IL‐34 may be an additional therapeutic target of DLBCL.

Prediction of steroid demand in the treatment of patients with ulcerative colitis by immunohistochemical analysis of the mucosal microenvironment and immune checkpoint: role of macrophages and regulatory markers in disease severity

We aimed to characterize the mucosal immune microenvironment and immune checkpoint of Ulcerative colitis (UC) by immunohistochemistry with correlation to prognosis: requirement of second-line steroid-therapy within the 2-years after diagnosis (SR). A series of 72 cases included 56 UC, 43 non-SR (with first-line treatment 5-ASA) and 13 SR, 11 infectious colitis and 5 normal colonic biopsies. Normal mucosa was characterized by low infiltrates but high BTLA and TNFRSF14. Compared to normal, UC had increased pan-immune-markers of CD3, CD8, FOXP3, PD-1, CD68, CD16, CD163, PTX3 and CD11C but had decreased BTLA (P < 0.05); by GSEA analysis comparable results were found in an independent UC gene-expression-data set (GSE38713). Compared to infectious, UC had higher CD4, CD8, PTX3 and CD11C but lower BTLA (P < 0.05). Compared to non-SR, SR had lower FOXP3 + Tregs (Odds-Ratio = 0.114, P = 0.002), PD-1 (OR = 0.176, P = 0.002) and CD163/CD68 M2-ratio (OR, 0.019, P = 0.019) but higher CD68 + pan-macrophages (OR = 6.034, P = 0.002). Higher Baron endoscopic and Geboes histologic disease activity scores also correlated with SR. In summary, UC was characterized by increased pan-immune-markers, normal TNFRSF14 and low BTLA. SR had increased CD68 + pan-macrophages but lower immune inhibitors of FOXP3 + Tregs, PD-1 and CD163/CD68 M2-macrophage ratio. In conclusion, alterations of the immune homeostasis mechanisms are relevant in the UC pathogenesis and steroid-requiring situation.

Clinical features and outcome of the patients with sinonasal tract diffuse large B-cell lymphoma in the pre-rituximab and rituximab eras

PURPOSE

Sinonasal tract diffuse large B-cell lymphoma (SNT-DLBCL), a rare extranodal lymphoma, is not well characterized. We performed a population-based study to determine cell-of-origin, clinical presentation and impact of rituximab (R) and central nervous system (CNS) directed chemotherapy on survival.

PATIENTS AND METHODS

Patients with SNT-DLBCL were identified from pathology databases. Clinical information was collected and outcomes between different treatment modalities evaluated.

RESULTS

Thirty-two percent of the patients had germinal centre B-cell phenotype. Forty-six patients were treated with curative intent using CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) or CHOP-like chemotherapy, 21 (46%) before and 25 (54%) in the R-era. Additionally, 24 (52%) received CNS-directed chemotherapy. Addition of R to chemotherapy reduced the risk of progression (RR = 0.368, 95% CI 0.138-0.976, P = 0.045) and death (RR = 0.245, 95% CI 0.068-0.883, P = 0.032), and translated into better survival (5-year PFS, 67% vs 38%, P = 0.037; 5-year OS, 81% vs 48%, P = 0.020). CNS-directed chemotherapy reduced the risk of progression (RR = 0.404, 95% CI 0.159-1.029, P = 0.057) and death (RR = 0.298, 95% CI 0.093-0.950, P = 0.041), and translated into favorable survival (5-year PFS, 67% vs 32%, P = 0.050; 5-year OS 82% vs 43%, P = 0.030).

CONCLUSION

Patients with SNT-DLBCL benefit from rituximab and CNS-directed chemotherapy.

Genetic Analysis of Rare Human Variants of Regulators of G Protein Signaling Proteins and Their Role in Human Physiology and Disease

Regulators of G protein signaling (RGS) proteins modulate the physiologic actions of many neurotransmitters, hormones, and other signaling molecules. Human RGS proteins comprise a family of 20 canonical proteins that bind directly to G protein-coupled receptors/G protein complexes to limit the lifetime of their signaling events, which regulate all aspects of cell and organ physiology. Genetic variations account for diverse human traits and individual predispositions to disease. RGS proteins contribute to many complex polygenic human traits and pathologies such as hypertension, atherosclerosis, schizophrenia, depression, addiction, cancers, and many others. Recent analysis indicates that most human diseases are due to extremely rare genetic variants. In this study, we summarize physiologic roles for RGS proteins and links to human diseases/traits and report rare variants found within each human RGS protein exome sequence derived from global population studies. Each RGS sequence is analyzed using recently described bioinformatics and proteomic tools for measures of missense tolerance ratio paired with combined annotation-dependent depletion scores, and protein post-translational modification (PTM) alignment cluster analysis. We highlight selected variants within the well-studied RGS domain that likely disrupt RGS protein functions and provide comprehensive variant and PTM data for each RGS protein for future study. We propose that rare variants in functionally sensitive regions of RGS proteins confer profound change-of-function phenotypes that may contribute, in newly appreciated ways, to complex human diseases and/or traits. This information provides investigators with a valuable database to explore variation in RGS protein function, and for targeting RGS proteins as future therapeutic targets.

Extranodal Diffuse Large B Cell Lymphoma: Molecular Features, Prognosis, and Risk of Central Nervous System Recurrence

OPINION STATEMENT

Diffuse large B cell lymphoma (DLBCL) arises from extranodal organs in about 30% of cases. Its prognosis and risk of recurrence in the central nervous system (CNS) vary according to the primary site of origin. Recent studies begin to clarify these differences using molecular classification. Testicular, breast, and uterine DLBCL (as well as possibly primary cutaneous DLBCL, leg-type) share a high prevalence of the non-germinal center B cell (non-GCB) phenotype and the MYD88/CD79B-mutated (MCD) genotype. These biologic features, which resemble primary CNS lymphoma, may underlie their stage-independent propensity for CNS involvement. Management of these lymphomas should involve CNS prophylaxis, preferably using systemic high-dose methotrexate to prevent intraparenchymal recurrence. Involvement of the kidneys, adrenal glands, ovary, bone marrow, lung, or pleura usually indicates disseminated disease, conferring worse prognosis. Involvement of these sites is often associated with high CNS-International Prognostic Index (IPI), concurrent MYC and BCL2 or BCL6 rearrangements, or intravascular lymphoma-risk factors warranting CNS prophylaxis. In contrast, craniofacial, thyroid, localized bone, or gastric lymphomas have a variable prevalence of the non-GCB phenotype and lack MYD88 mutations. Their outcomes with standard immunochemotherapy are excellent, and the risk of CNS recurrence is low. We recommend individualized consideration of CNS prophylaxis based on the CNS-IPI score and anatomical proximity in cases of epidural, orbital, or skull involvement. Rituximab-containing immunochemotherapy is a standard approach for all extranodal DLBCLs. Surgery is no longer required for any primary site, but routine consolidative radiation therapy is recommended for testicular lymphoma. Radiation therapy also appears to be associated with better progression-free survival in primary bone DLBCL. Future studies should better distinguish primary from secondary sites of extranodal involvement, and investigate the association of newly identified genotypes with the risk of CNS or systemic recurrence.

Clinicopathological and genomic analysis of double-hit follicular lymphoma: comparison with high-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements

Most high-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements are aggressive B-cell lymphomas. Occasional double-hit follicular lymphomas have been described but the clinicopathological features of these tumors are not well known. To clarify the characteristics of double-hit follicular lymphomas, we analyzed 10 cases of double-hit follicular lymphomas and 15 cases of high-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements for clinicopathological and genome-wide copy-number alterations and copy-neutral loss-of-heterozygosity profiles. For double-hit follicular lymphomas, the median age was 67.5 years (range: 48-82 years). The female/male ratio was 2.3. Eight patients presented with advanced clinical stage. The median follow-up time was 20 months (range: 1-132 months). At the end of the follow-up, 8 patients were alive, 2 patients were dead including 1 patient with diffuse large B-cell lymphoma transformation. Rearrangements of MYC/BCL2, MYC/BCL6, and MYC/BCL2/BCL6 were seen in 8, 1, and 1 cases, respectively. The partner of MYC was IGH in 6 cases. There were no cases of histological grade 1, 4 cases of grade 2, 5 cases of grade 3a, and 1 case of grade 3b. Two cases of grade 3a exhibited immunoblast-like morphology. Immunohistochemistry demonstrated 9 cases with ≥50% MYC-positive cells. There was significant difference in MYC intensity (P=0.00004) and MIB-1 positivity (P=0.001) between double-hit follicular lymphomas and high-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements. The genome profile of double-hit follicular lymphomas was comparable with conventional follicular lymphomas (GSE67385, n=198) with characteristic gains of 2p25.3-p11.1, 7p22.3-q36.3, 12q11-q24.33, and loss of 18q21.32-q23 (P<0.05). In comparison with high-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements, double-hit follicular lymphomas had fewer copy-number alterations and minimal common region of gain at 2p16.1 (70%), locus also significant against conventional follicular lymphomas (P=0.0001). In summary, double-hit follicular lymphomas tended to be high-grade histology, high MYC protein expression, high MYC/IGH fusion, and minimal common region of gain at 2p16.1. Double-hit follicular lymphomas seemed to be a different disease from high-grade B-cell lymphomas with MYC and BCL2 and/or BCL6 rearrangements and have an indolent clinical behavior similar to follicular lymphomas without MYC rearrangement.