Diffuse large B-cell lymphoma variants: an update

Silencing Aurora-kinase-A (AURKA) reinforced the sensitivity of diffuse large B-cell lymphoma cells to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) via suppressing β-Catenin and RAS-extracellular signal-regulated protein kinase (ERK1/2) pathway

The therapeutic effects of standard cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) therapy for prevalent lymphoma diffuse large B-cell lymphoma (DLBC, DLBCL) still require improvement. Cancer-related aurora-kinase-A (AURKA) may work as a target for DLBCL treatment and its effect on CHOP therapy was investigated in the present study. The Gene Expression Profiling Interactive Analysis 2 was applied to analyze AURKA expression in DLBC tumor tissues and normal lymphoid tissues. The DLBCL tissues and normal lymphoid tissues were obtained from the DLBCL patients and healthy volunteers. Clinic data of patients were recorded, and AURKA expression in tissues and cells was detected and analyzed using quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry. After AURKA in DLBCL cells was silenced or overexpressed and treated with CHOP, viability and apoptosis were detected by Cell Counting Kit-8 (CCK-8) assay and flow cytometry. Expressions of AURKA, β-Catenin, phosphorylated (p)-β-Catenin, extracellular signal-regulated protein kinase (ERK1/2), p-ERK1/2 and RAS were detected using qRT-PCR and Western blot. AURKA was highly expressed in DLBCL tissues and cells. Silencing AURKA inhibited AURKA expression and viability, but promoted apoptosis of DLBCL cells. CHOP had no obvious effects on AURKA expression while reducing viability and promoting apoptosis of DLBCL cells. Silencing AURKA enhanced the effects of CHOP on cell apoptosis of DLBCL cells by inhibiting the expressions of RAS and β-Catenin as well as the ratio of p-ERK1/2/ERK1/2 and promoting the ratio of p-β-Catenin/β-Catenin. Silencing AURKA reinforced the therapeutic effects of CHOP on reducing viability and promoting apoptosis of DLBCL cell via repressing β-Catenin and RAS-ERK1/2 pathway.

Dysregulation of miRNAs in DLBCL: Causative Factor for Pathogenesis, Diagnosis and Prognosis

MicroRNA is a small non-coding RNA (sncRNA) involved in gene silencing and regulating post-transcriptional gene expression. miRNAs play an essential role in the pathogenesis of numerous diseases, including diabetes, cardiovascular diseases, viral diseases and cancer. Diffuse large B-cell lymphoma (DLBCL) is an aggressive non-Hodgkin’s lymphoma (NHL), arising from different stages of B-cell differentiation whose pathogenesis involves miRNAs. Various viral and non-viral vectors are used as a delivery vehicle for introducing specific miRNA inside the cell. Adenoviruses are linear, double-stranded DNA viruses with 35 kb genome size and are extensively used in gene therapy. Meanwhile, Adeno-associated viruses accommodate up to 4.8 kb foreign genetic material and are favorable for transferring miRNA due to small size of miRNA. The genetic material is integrated into the DNA of the host cell by retroviruses so that only dividing cells are infected and stable expression of miRNA is achieved. Over the years, remarkable progress was made to understand DLBCL biology using advanced genomics and epigenomics technologies enabling oncologists to uncover multiple genetic mutations in DLBCL patients. These genetic mutations are involved in epigenetic modification, ability to escape immunosurveillance, impaired BCL6 and NF-κβ signaling pathways and blocking terminal differentiation. These pathways have since been identified and used as therapeutic targets for the treatment of DLBCL. Recently miRNAs were also identified to act either as oncogenes or tumor suppressors in DLBCL pathology by altering the expression levels of some of the known DLBCL related oncogenes. i.e., miR-155, miR-17-92 and miR-21 act as oncogenes by altering the expression levels of MYC, SHIP and FOXO1, respectively, conversely; miR-34a, mir-144 and miR-181a act as tumor suppressors by altering the expression levels of SIRT1, BCL6 and CARD11, respectively. Hundreds of miRNAs have already been identified as biomarkers in the prognosis and diagnosis of DLBCL because of their significant roles in DLBCL pathogenesis. In conclusion, miRNAs in addition to their role as biomarkers of prognosis and diagnosis could also serve as potential therapeutic targets for treating DLBCL.

Diagnostic utility of programmed cell death ligand 1 (clone SP142) immunohistochemistry for malignant lymphoma and lymphoproliferative disorders: A brief review

The programmed cell death 1 (PD1)/PD1 ligand (PD-L1) axis plays an important role in tumor cell escape from immune control and has been most extensively investigated for therapeutic purposes. However, PD-L1 immunohistochemistry is still not used widely for diagnosis. We review the diagnostic utility of PD-L1 (by clone SP142) immunohistochemistry in large-cell lymphomas, mainly consisting of classic Hodgkin lymphoma (CHL) and diffuse large B-cell lymphoma (DLBCL). Neoplastic PD-L1 (nPD-L1) expression on Hodgkin and Reed-Sternberg cells is well-established among prototypic CHL. Of note, EBV+ CHL often poses a challenge for differential diagnosis from peripheral T-cell lymphoma with EBV+ non-malignant large B-cells; their distinction is based on the lack of PD-L1 expression on large B-cells in the latter. The nPD-L1 expression further provides a good diagnostic consensus for CHL with primary extranodal disease conceivably characterized by a combined pathogenesis of immune escape of tumor cells and immunodeficiency. Compared with CHL, the nPD-L1 expression rate is much lower in DLBCL, highlighting some specific subgroups of intravascular large B-cell lymphoma, primary mediastinal large B-cell lymphoma, and EBV+ DLBCL. They consist of nPD-L1-positive and -negative subgroups, but their clinicopathological significance remains to be elucidated. Microenvironmental PD-L1 positivity on immune cells may be associated with a favorable prognosis in extranodal DLBCL. PD-L1 (by SP142) immunohistochemistry has helped us to understand the immune biology of lymphoid neoplasms possibly related by immune escape and/or immunodeficiency. However, knowledge of these issues remains limited and should be clarified for diagnostic consensus in the future.

Painful purpura from intravascular large B-cell lymphoma cutaneous variant

Intravascular large B-cell lymphoma is a rare disease that often goes unnoticed and is repeatedly diagnosed during autopsy. Patients present with a wide variety of nonspecific symptoms, which makes the diagnosis challenging. This case presents a patient who was initially diagnosed with fever of unknown origin but later developed a retiform purpuric rash that prompted the diagnosis.

Pyruvate dehydrogenase kinase 4-mediated metabolic reprogramming is involved in rituximab resistance in diffuse large B-cell lymphoma by affecting the expression of MS4A1/CD20

Diffuse large B cell lymphoma (DLBCL) heterogeneity promotes recurrence and anti‐CD20‐based therapeutic resistance. Previous studies have shown that downregulation of MS4A1/CD20 expression after chemoimmunotherapy with rituximab leads to rituximab resistance. However, the mechanisms of CD20 loss remain unknown. We identified that pyruvate dehydrogenase kinase 4 (PDK4) is markedly elevated in DLBCL cells derived from both patients and cell lines with R‐CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) resistance. We found that overexpression of PDK4 in DLBCL cells resulted in cell proliferation and resistance to rituximab in vitro and in vivo. Furthermore, loss of PDK4 expression or treatment with the PDK4 inhibitor dichloroacetate was able to significantly increase rituximab‐induced cell apoptosis in DLBCL cells. Further studies suggested PDK4 mediates a metabolic shift, in that the main energy source was changed from oxidative phosphorylation to glycolysis, and the metabolic changes could play an important role in rituximab resistance. Importantly, by knocking down or overexpressing PDK4 in DLBCL cells, we showed that PDK4 has a negative regulation effect on MS4A1/CD20 expression. Collectively, this is the first study showing that targeting PDK4 has the potential to overcome rituximab resistance in DLBCL.

Molecular Update and Evolving Classification of Large B-Cell Lymphoma

Simple Summary

The development of high-throughput technologies in recent years has increased our understanding of the molecular complexity of lymphomas, providing new insights into the pathogenesis of large B-cell neoplasms and identifying different molecular biomarkers with prognostic impact, that lead to the revision of the World Health Organization consensus classification of lymphomas. This review addresses the main histopathological and molecular features of large B-cells lymphomas, providing an overview of the main recent novelties introduced by the last update of the consensus classification.

Abstract

Diffuse large B-cell lymphomas (DLBCLs) are aggressive B-cell neoplasms with considerable clinical, biologic, and pathologic diversity. The application of high throughput technologies to the study of lymphomas has yielded abundant molecular data leading to the identification of distinct molecular identities and novel pathogenetic pathways. In light of this new information, newly refined diagnostic criteria have been established in the fourth edition of the World Health Organization (WHO) consensus classification of lymphomas, which was revised in 2016. This article reviews the histopathological and molecular features of the various aggressive B-cell lymphoma subtypes included in the updated classification.

Light chain cast nephropathy caused by plasmablastic lymphoma of the bladder

Introduction: Plasmablastic lymphoma (PBL) is a rare form of B-cell lymphoma typically seen in patients with underlying immunosuppression such as HIV, autoimmune disease, and organ transplantation. PBL in HIV-positive patients usually originates from the gastrointestinal tract, with a predilection for the oral cavity. Bladder involvement by PBL is exceedingly rare, and cast nephropathy due to κ light chain-secreting PBL has not been reported previously. Case report: We report a patient who presented with acute kidney injury (AKI) in the setting of HIV, and was found to have a bladder tumor. Bladder pathology revealed a high-grade PBL with κ light chain restriction. Renal biopsy showed κ light chain cast nephropathy, presumably secondary to κ light chain-secreting PBL. Conclusion: Although the prognosis of PBL is poor, our patient recovered from AKI, achieved complete hematologic remission with chemotherapy, and underwent successful autologous stem cell transplant.

Anaplastic lymphoma kinase-positive large B-cell lymphoma (ALK + LBCL): a systematic review of clinicopathological features and management

Anaplastic lymphoma kinase-positive (ALK+) large B-cell lymphoma (LBCL) is a rare CD20-negative aggressive lymphoma. Given its rarity, data on ALK + LBCL are scarce and limited to case reports and small case series. Our systematic review included 184 unique cases published in the literature and shows that ALK + LBCL can affect individuals at any age, has a male predominance and is not associated with chronic viral infections. The malignant cells express ALK, VS38c, BLIMP-1, EMA, c-MYC, and BOB-1. The STAT3/STAT5, PI3K/AKT, PLCG2, and ERK pathways are important in the pathophysiology of ALK + LBCL. The prognosis of ALK + LBCL is poor with a 5-year survival rate of 28%. Early disease stage is associated with better outcomes. ALK inhibitors and other targeted agents could be of value in the treatment of ALK + LBCL. Additional research is needed to better understand, diagnose and treat ALK + LBCL.

A rare case of primary cutaneous diffuse large B-cell lymphoma, leg type, presenting as cellulitis: a case report

Primary cutaneous diffuse large B-cell lymphoma, leg type, accounts for only 4% of all cutaneous lymphomas and bears a worse prognosis than other cutaneous B-cell lymphomas. Diagnosis at an early stage may be difficult due to its nonspecific manifestations. We report an 88-year-old female who was brought to our emergency department due to two rapidly growing painful skin lesions with local redness and swelling on her right lower leg. We performed incisional biopsy of the two right lower leg skin lesions and sent the specimens for histopathological examination. The pathological examination was compatible with diffuse large B-cell lymphoma. Primary cutaneous diffuse large B-cell lymphoma, leg type, is a rare condition that can present as skin cellulitis, thereby misleading clinicians and resulting in delayed treatment. This diagnosis should be considered when assessing skin lesions.

Advances in the Pathogenesis of EBV-Associated Diffuse Large B Cell Lymphoma

Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin's lymphoma (NHL) in adults. Epstein-Barr virus (EBV) positive DLBCL of the elderly was defined by the World Health Organization (WHO) in 2008, it was restricted only to patients older than 50 years old, and it was attributed to immunesenescence associated with physiological aging. After the description of EBV-associated DLBCL in children and young adults, the WHO redefined the definition, leading to the substitution of the modifier "elderly" with "not otherwise specified" (EBV + DLBCL, NOS) in the updated classification, and it is no more considered provisional. The incidence of EBV + DLBCL, NOS varies around the world, in particular influenced by the percentage of EBV+ cells used as cut-off to define a case as EBV-associated. EBV has effect on the genetic composition of tumor cells, on survival, and at the recruitment of immune cells at the microenvironment. In this review, the role of EBV in the pathogenesis of DLBCL is discussed.

Current and emerging therapies for primary central nervous system lymphoma

Primary central nervous system (CNS) lymphoma (PCNSL) is a rare type of extranodal lymphoma exclusively involving the CNS at the onset, with diffuse large B-cell lymphoma (DLBCL) as the most common histological subtype. As PCNSL is a malignancy arising in an immune-privileged site, suboptimal delivery of systemic agents into tumor tissues results in poorer outcomes in PCNSL than in non-CNS DLBCLs. Commonly used regimens for PCNSL include high-dose methotrexate-based chemotherapy with rituximab for induction therapy and intensive chemotherapy followed by autologous hematopoietic stem cell transplantation or whole-brain radiotherapy for consolidation therapy. Targeted agents against the B-cell receptor signaling pathway, microenvironment immunomodulation and blood-brain barrier (BBB) permeabilization appear to be promising in treating refractory/relapsed patients. Chimeric antigen receptor-T cells (CAR-T cells) have been shown to penetrate the BBB as a potential tool to manipulate this disease entity while controlling CAR-T cell-related encephalopathy syndrome. Future approaches may stratify patients according to age, performance status, molecular biomarkers and cellular bioinformation. This review summarizes the current therapies and emerging agents in clinical development for PCNSL treatment.

TUC338 Promotes Diffuse Large B Cell Lymphoma Growth via Regulating EGFR/PI3K/AKT Signaling Pathway

TUC338 is emerging as a novel vital long noncoding RNA (lncRNA) in human cancer; however, its role in diffuse large B cell lymphoma (DLBCL) remains unknown. In this study, we found that TUC338 was remarkably upregulated in DLBCL tissues as compared to matched normal tissues. High TUC338 was closely related to advanced Ann Arbor stage, resistance to CHOP-like treatment, and high IPI (International Prognostic Index). Stable knockdown of TUC338 evidently inhibited cell proliferation and chemotherapy resistance to Adriamycin and induced apoptosis. Further, we found that TUC338 was able to directly bind to miR-28-5p and increased EGFR level, resulting in activating carcinogenic PI3K/AKT signaling, thereby facilitating DLBCL uncontrolled growth. Moreover, we also found that depletion of TUC338 led to the inactivation of EGFR/PI3K/AKT pathway in vivo by using the xenograft tumor model. Preclinically, DLBCL patients with high TUC338 had shorter survival time than those with low TUC338, and serum TUC338 level was identified as an excellent indicator for DLBCL diagnosis. In sum, our findings clearly indicate that TUC338 functions as an oncogenic lncRNA in DLBCL through activating EGFR/PI3K/AKT pathway via sponging and inhibiting miR-28-5p, which may be a promising target for DLBCL treatment.

LncRNA SNHG8 Promotes Proliferation and Inhibits Apoptosis of Diffuse Large B-Cell Lymphoma via Sponging miR-335-5p

Long-chain non-coding RNAs (LncRNAs) are expressed in diffuse large B-cell lymphoma (DLBCL) tissues and have played a regulatory role in DLBCL with a cancer-promoting effect. In this study, the role of LncRNA SNHG8 in the regulation of DLBCL cells is investigated, and its underlying mechanism is explored. The database of the Gene Expression Profiling Interactive Analysis (GEPIA) was searched, and the expression of SNHG8 in DLBCL and normal tissues was examined. The expression of SNHG8 was evaluated in several DLBCL cell lines and a normal lymphocyte cell line. It was found that SNHG8 was overexpressed in DLBCL tissues and cells in comparison with their normal counterparts. The short hairpin RNA (shRNA) plasmids of SNHG8 were transfected into DLBCL cells to knockdown the expression of SNHG8, followed by assays of proliferation, colony formation, apoptosis, and related protein expression. The results showed that the knockdown of SNHG8 significantly inhibited DLBCL cell proliferation and colony formation while promoting cell apoptosis. Moreover, the knockdown of SNHG8 reduced the expression of Ki-67, proliferating cell nuclear antigen (PCNA), and Bcl-2 and enhanced the expression of Bax and cleaved caspase 3/9. MiR-335-5p was predicted to be a potential target of SNHG8 by using the bioinformatics analysis, and the interaction between the two was validated by using the dual luciferase assay. In addition, the knockdown of SNHG8 increased the level of miR-335-5p, whereas miR-335-5p mimic decreased the expression of SNHG8. Finally, U2932 cells were co-transfected with or without sh-SNHG8 and miR-335-5p inhibitors, whose proliferation, colony formation, and apoptosis were determined subsequently. It was demonstrated that the presence of an miR-335-5p inhibitor partially canceled the inhibitory effects of the knockdown of SNHG8 on DLBCL cell proliferation and colony formation and the stimulating effects of the knockdown of SNHG8 on cell apoptosis. Taken together, our study suggests that lncRNA SNHG8 exerts a cancer-promoting effect on DLBCL via targeting miR-335-5p.

Non-coding RNAs (miRNAs and lncRNAs) and their roles in lymphogenesis in all types of lymphomas and lymphoid malignancies

Contemporary developments in molecular biology have been combined with discoveries on the analysis of the role of all non-coding RNAs (ncRNAs) in human diseases, particularly in cancer, by examining their roles in cells. Currently, included among these common types of cancer, are all the lymphomas and lymphoid malignancies, which represent a diverse group of neoplasms and malignant disorders. Initial data suggest that non-coding RNAs, particularly long ncRNAs (lncRNAs), play key roles in oncogenesis and that lncRNA-mediated biology is an important key pathway to cancer progression. Other non-coding RNAs, termed microRNAs (miRNAs or miRs), are very promising cancer molecular biomarkers. They can be detected in tissues, cell lines, biopsy material and all biological fluids, such as blood. With the number of well-characterized cancer-related lncRNAs and miRNAs increasing, the study of the roles of non-coding RNAs in cancer is bringing forth new hypotheses of the biology of cancerous cells. For the first time, to the best of our knowledge, the present review provides an up-to-date summary of the recent literature referring to all diagnosed ncRNAs that mediate the pathogenesis of all types of lymphomas and lymphoid malignancies.

Spatial signatures identify immune escape via PD-1 as a defining feature of T-cell/histiocyte-rich large B-cell lymphoma

T-cell/histiocyte-rich large B-cell lymphoma (TCRLBCL) is an aggressive variant of diffuse large B-cell lymphoma (DLBCL) characterized by rare malignant B cells within a robust but ineffective immune cell infiltrate. The mechanistic basis of immune escape in TCRLBCL is poorly defined and not targeted therapeutically. We performed a genetic and quantitative spatial analysis of the PD-1/PD-L1 pathway in a multi-institutional cohort of TCRLBCLs and found that malignant B cells harbored PD-L1/PD-L2 copy gain or amplification in 64% of cases, which was associated with increased PD-L1 expression (P = .0111). By directed and unsupervised spatial analyses of multiparametric cell phenotypic data within the tumor microenvironment, we found that TCRLBCL is characterized by tumor-immune "neighborhoods" in which malignant B cells are surrounded by exceptionally high numbers of PD-L1-expressing TAMs and PD-1+ T cells. Furthermore, unbiased clustering of spatially resolved immune signatures distinguished TCRLBCL from related subtypes of B-cell lymphoma, including classic Hodgkin lymphoma (cHL) and DLBCL-NOS. Finally, we observed clinical responses to PD-1 blockade in 3 of 5 patients with relapsed/refractory TCRLBCL who were enrolled in clinical trials for refractory hematologic malignancies (NCT03316573; NCT01953692), including 2 complete responses and 1 partial response. Taken together, these data implicate PD-1 signaling as an immune escape pathway in TCRLBCL and also support the potential utility of spatially resolved immune signatures to aid the diagnostic classification and immunotherapeutic prioritization of diverse tumor types.

Lifetime Impact of Cow's Milk on Overactivation of mTORC1: From Fetal to Childhood Overgrowth, Acne, Diabetes, Cancers, and Neurodegeneration

The consumption of cow's milk is a part of the basic nutritional habits of Western industrialized countries. Recent epidemiological studies associate the intake of cow's milk with an increased risk of diseases, which are associated with overactivated mechanistic target of rapamycin complex 1 (mTORC1) signaling. This review presents current epidemiological and translational evidence linking milk consumption to the regulation of mTORC1, the master-switch for eukaryotic cell growth. Epidemiological studies confirm a correlation between cow's milk consumption and birthweight, body mass index, onset of menarche, linear growth during childhood, acne vulgaris, type 2 diabetes mellitus, prostate cancer, breast cancer, hepatocellular carcinoma, diffuse large B-cell lymphoma, neurodegenerative diseases, and all-cause mortality. Thus, long-term persistent consumption of cow's milk increases the risk of mTORC1-driven diseases of civilization. Milk is a highly conserved, lactation genome-controlled signaling system that functions as a maternal-neonatal relay for optimized species-specific activation of mTORC1, the nexus for regulation of eukaryotic cell growth, and control of autophagy. A deeper understanding of milk´s impact on mTORC1 signaling is of critical importance for the prevention of common diseases of civilization.

Pediatric Lymphoid and Histiocytic Lesions in the Head and Neck

Lymphoid and histiocytic lesions of the head and neck in pediatric patients is a fascinating topic as most of these lesions are benign, but that the neoplastic cases are essential to diagnose accurately for appropriate treatment. It is thought that 90% of children will have palpable lymph nodes between the ages of 4 to 8; most, but not all, are non-malignant and some resolve spontaneously without treatment. This paper will look at many of the benign and malignant lesions of both lymphocytic and histiocytic origin that present in the head and neck of children focusing on their diagnostic criteria. There is a very pertinent discussion of nonmalignant lymphoid proliferations, as infections and other reactive conditions dominate the pathology of pediatric lymphohistiocytic head and neck lesions. Discussion of those lymphomas which arise more frequently in the head and neck focuses on those seen in children and young adults such as classic Hodgkin lymphoma and Burkitt lymphoma, as well as new more controversial entities such as pediatric-type follicular lymphoma. Histiocytic lesions, both benign and malignant, are described and may be challenging to diagnose.

Use of immune repertoire sequencing to resolve discordant microscopic and immunochemical findings in a case of T cell-rich large B cell lymphoma in a young dog

Background

Lymphocytic neoplasms with frequent reactive lymphocytes are uncommonly reported in dogs, and can pose a diagnostic challenge. Different diagnostic modalities such as cytology, flow cytometry, histopathology, immunohistochemistry, and clonality testing, are sometimes required for a diagnosis. This report illustrates the value of using a multi-modal diagnostic approach to decipher a complex lymphocytic tumor, and introduces immune repertoire sequencing as a diagnostic adjunct.

Case presentation

A 10-month-old Great Dane was referred for marked ascites. Cytologic analysis of abdominal fluid and hepatic aspirates revealed a mixed lymphocyte population including numerous large lymphocytes, yielding a diagnosis of lymphoma. Flow cytometrically, abdominal fluid lymphocytes were highly positive for CD4, CD5, CD18, CD45, and MHC II, consistent with T cell lymphoma. Due to a rapidly deteriorating clinical condition, the dog was euthanized. Post mortem histologic evaluation showed effacement of the liver by aggregates of B cells surrounded by T cells, suggestive of hepatic T cell-rich large B cell lymphoma. Immune repertoire sequencing confirmed the presence of clonal B cells in the liver but not the abdominal fluid, whereas reactive T cells with shared, polyclonal immune repertoires were found in both locations.

Conclusions

T cell-rich large B cell lymphoma is a rare neoplasm in dogs that may be challenging to diagnose and classify due to mixed lymphocyte populations. In this case, the results of histopathology, immunohistochemistry and immune repertoire sequencing were most consistent with a hepatic B cell neoplasm and reactive T cells exfoliating into the abdominal fluid. Immune repertoire sequencing was helpful in delineating neoplastic from reactive lymphocytes and characterizing repertoire overlap in both compartments. The potential pitfalls of equating atypical cytomorphology and monotypic marker expression in neoplasia are highlighted.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-021-02783-3.

Identification of a miRNA based model to detect prognostic subgroups in patients with aggressive B-cell lymphoma

In order to differentiate prognostic subgroups of patients with aggressive B-cell lymphoma, we analyzed the expression of 800 miRNAs with the NanoString nCounter human miRNA assay on a cohort of 228 FFPE samples of patients enrolled in the RICOVER-60 and MegaCHOEP trials. We identified significant miRNA signatures for overall survival (OS) and progression-free survival (PFS) by LASSO-penalized linear Cox-regression. High expression levels of miR-130a-3p and miR-423-5p indicate a better prognosis, whereas high levels of miR-374b-5p, miR-590-5p, miR-186-5p, and miR-106b-5p increase patients' risk levels for OS. Regarding PFS high expression of miR-365a-5p in addition to the other two miRNAs improves the prognosis and high levels of miR374a-5p, miR-106b-5p, and miR-590-5p, connects with increased risk and poor prognosis. We identified miRNA signatures to subdivide patients into two different risk groups. These prognostic models may be used in risk stratification in future clinical trials and help making personalized therapy decisions.

Intravascular Large B-Cell Lymphoma and Renal Clear Cell Carcinoma as Collision Tumor: A Case Report and Review of the Literature

Intravascular large B-cell lymphoma (IVLBCL) is a rare type of extranodal large B-cell lymphoma characterized by the selective growth of lymphoma cells within the lumina of vessels. The patient usually presents with nonspecific symptoms and a remarkable deterioration in performance status. The occurrence of synchronous IVLBCL and renal cell carcinoma (RCC) is extremely rare. A right kidney tumor was found in a 72-year-old man with a history of low back pain. The kidney was enlarged, with a tumor mass measuring 4.5 × 4 × 4 cm. Sections exhibited a RCC (clear cell type, nuclear grade I). Also an extensive tumor affecting capillaries and small veins was present, positive for CD45, CD20, BCL-2, and MUM1/IRF-4, consistent with IVLBCL. The lymphoma was circumscribed to the RCC. The final diagnosis was IVLBCL with a RCC as collision tumor. After that, with neurological findings, central nervous system compromise by lymphoma was made. The patient started a first cycle of chemotherapy, progressive deterioration of the sensorium, and positive blood cultures for Klebsiella pneumoniae and Escherichia coli. The patient died 8 days later of acute respiratory failure. No autopsy was done. IVLBCL is an aggressive and systemic disease characterized by massive proliferation of tumor cells without a known primary site. Clinical identification and histopathologic diagnosis are relevant issues in the therapeutic management of these lymphomas. Until now, only one case of IVLBCL coexisting with RCC has been reported. In this article, we report a second case of IVLBCL with RCC simultaneous, as an unusual collision tumor.

Hodgkin Reed-Sternberg-Like Cells in Non-Hodgkin Lymphoma

Reed-Sternberg cells (RSCs) are hallmarks of classic Hodgkin lymphoma (cHL). However, cells with a similar morphology and immunophenotype, so-called Reed-Sternberg-like cells (RSLCs), are occasionally seen in both B cell and T cell non-Hodgkin Lymphomas (NHLs). In NHLs, RSLCs are usually present as scattered elements or in small clusters, and the typical background microenviroment of cHL is usually absent. Nevertheless, in NHLs, the phenotype of RSLCs is very similar to typical RSCs, staining positive for CD30 and EBV, and often for B cell lineage markers, and negative for CD45/LCA. Due to different therapeutic approaches and prognostication, it is mandatory to distinguish between cHL and NHLs. Herein, NHL types in which RSLCs can be detected along with clinicopathological correlation are described. Moreover, the main helpful clues in the differential diagnosis with cHL are summarized.

Extracavitary primary effusion lymphoma recurring with syphilis in an HIV-infected patient

A 59-year-old Caucasian man infected with HIV, in remission from human herpes virus-8-positive extracavitary primary effusion lymphoma (EC-PEL), presented to a sexual health clinic with fever and rectal pain 10 weeks after a single episode of receptive anal sexual intercourse with another man. He was initially treated for a presumptive diagnosis of lymphogranuloma venereum proctitis, then for syphilis on positive serology. Rectosigmoidoscopy revealed a single ulcerated rectal mass; endoscopic biopsies confirmed the recurrence of EC-PEL. The patient received chemotherapy and went into remission. This is the first reported case of EC-PEL occurring synchronously with early syphilis, and specifically at the site of inoculation, which can be a major diagnostic challenge since both conditions may present with lymphadenopathy, mucosal involvement and constitutional symptoms. We reviewed the literature for similar cases and hypothesised that syphilis may have triggered the recurrence of this rare lymphoma.

Biomarkers and novel therapeutic approaches for diffuse large B-cell lymphoma in the era of precision medicine

Despite the great efforts for better treatment options for diffuse large B-cell lymphoma (DLBCL) (most common form of non-Hodgkin lymphoma, NHL) to treat and prevent relapse, it continues to be a challenge. Here, we present an overview of DLBCL and address the diagnostic assays and molecular techniques used in its diagnosis, role of biomarkers in detection, treatment of early and advanced stage DLBCL, and novel drug regimens. We discuss the significant biomarkers that have emerged as essential tools for stratifying patients according to risk factors and for providing insights into the use of more targeted and individualized therapeutics. We discuss techniques such as gene expression studies, including next-generation sequencing, which have enabled a more understanding of the complex pathogenesis of DLBCL and have helped determine molecular targets for novel therapeutic agents. We examine current treatment approaches, outline the findings of completed clinical trials, and provide updates for ongoing clinical trials. We highlight clinical trials relevant to the significant fraction of DLBCL patients who present with complex cases marked by high relapse rates. Supported by an increased understanding of targetable pathways in DLBCL, clinical trials involving specialized combination therapies are bringing us within reach the promise of an effective cure to DLBCL using precision medicine. Optimization of therapy remains a crucial objective, with the end goal being a balance between high survival rates through targeted and personalized treatment while reducing adverse effects in DLBCL patients of all subsets.

American Registry of Pathology Expert Opinions: Recommendations for the diagnostic workup of mature T cell neoplasms

The diagnosis of T-cell lymphomas is highly challenging and requires an integrated approach in which clinical, morphologic, immunophenotypic and molecular data are incorporated into the diagnosis. Under the auspices of the American Registry of Pathology, the authors met to discuss this topic with the goal to provide practical and useful recommendations for pathologists when evaluating T-cell lymphomas. In this review, we discuss the diagnostic findings and workup for the various types of nodal T-cell lymphoma including anaplastic large cell lymphoma, nodal peripheral T-cell lymphoma not otherwise specified (PTCL-NOS), and PTCL with a T follicular helper (TFH) phenotype. We review clinicopathologic and immunophenotypic features (including flow cytometry panels) helpful in the differential diagnosis of mature T-cell lymphomas presenting in the peripheral blood and bone marrow, and we discuss some of the more common extranodal-based T-cell lymphomas including extranodal natural killer/T-cell lymphoma of nasal and non-nasal type, gamma delta T cell lymphomas, and aggressive and indolent T- and NK-lymphoproliferative disorders involving the gastrointestinal tract. Mycosis fungoides and most other cutaneous T-cell lymphomas are not the focus of this review, although the differential diagnosis of Sezary syndrome from mycosis fungoides is covered. We do not intend for these recommendations to be anything other than suggestions that will hopefully spur on additional discussion, and perhaps eventually evolve into a consensus approach for the workup of T-cell lymphomas.

Primary Central Nervous System Lymphomatoid Granulomatosis: Systemic Review

Lymphomatoid granulomatosis (LYG) is an infrequent lymphoproliferative disease that typically involves the lungs, but may also affect the central nervous system (CNS). Isolated CNS involvement is very rare, and its clinicopathological features have not been fully elucidated. Here, we systematically reviewed the English literature through PubMed to collect all relevant case reports and small case series with pathologically confirmed primary CNS-LYG. A total of 29 relevant articles with 40 cases were included in this systemic review. In cases where T cells and B cells were compared, T cells were predominant in 19 (79.2%), and B cells were predominant in 5 (20.8%). The overall infection rate of EBV was 48.1% (13/27), among which the infection rate was 40.9% (9/22) in immunocompetent patients and 80% (4/5) in immunodeficient (HIV-infected) patients. Among the patients who underwent pathological grading, 35.7% (5/14) were at grade I, 42.9% (6/14) were at grade II, and 21.4% were at grade III. In conclusion, primary CNS-LYG is closely related to EBV infection and some cases may be predominantly T-cell phenotype. Surgical resection may be effective for mass-like lesions, although there is still a lack of standard therapeutic regimen. Accurate grading of lesions is essential for treatment selection and prognosis evaluation.

Triplet Therapy with PD-1 Blockade, Histone Deacetylase Inhibitor, and DNA Methyltransferase Inhibitor Achieves Radiological Response in Refractory Double-Expressor Diffuse Large B-cell Lymphoma with 17p Deletion

Double-expressor diffuse large B-cell lymphoma (DLBCL) with 17p deletion is an aggressive and refractory disease. Immune checkpoint blockade and epigenetic drugs have been widely used, but the efficacy of different combined applications varied. We report a case with “double-expressor” DLBCL treated with a combined regimen which consisted of programmed cell death protein 1 (PD-1) inhibitor, DNA methyltransferase inhibitor (DNMTi), and histone deacetylase inhibitor (HDACi). A 50-year-old man presented with a 6-month history of hoarseness, and 10 days of progressive shortness of breath was diagnosed of DLBCL, stage IV. The patient failed to respond to the 1^st line (R-EPOCH: rituximab, etoposide, vincristine, cyclophosphamide, doxorubicin, and dexamethasone), 2^nd line (R-EPOCH + lenalidomide + ibrutinib), and a 3^rd line chemotherapy combined with PD-1 inhibitor (sintilimab), decitabine, and GDP (gemcitabine, DDP, and dexamethasone). Surprisingly, patient's condition was improved after treatment with PD-1 inhibitor in combination with DNMTi/HDACi. Restaging PET revealed dramatically radiological response.

EBV-positive intravascular large B-cell lymphoma of the liver: a case report and literature review

BACKGROUND

Intravascular large B-cell lymphoma (IVLBCL) is an extremely rare subtype of diffuse large B-cell lymphoma that most commonly involves the central nervous system, skin, and bone marrow. To our knowledge, Epstein-Barr virus (EBV)-positive IVLBCL in the liver has never been reported in the literature.

CASE PRESENTATION

We report a case of a 65-year-old Chinese man with complaint of fever for 18 days. No obvious abnormality was found by physical examination. Laboratory findings were notable for anemia, thrombocytopenia, and elevated level of serum lactate dehydrogenase. Bone marrow on smear, biopsy, and flow cytometry revealed no lymphoma. Imaging studies showed a slightly lower density lesion in the liver with high fluorodeoxyglucose uptake and hepatosplenomegaly. Percutaneous liver biopsy revealed clustering of large atypical lymphocytes within the hepatic sinusoids. Immunohistochemically, these lymphoma cells were positive for CD20, PAX-5, MUM-1, BCL-6 and CD5, but negative for CD3 and CD10. Besides, Epstein-Barr virus-encoded RNA was detected in tumor cells by in situ hybridization. BCL-2, BCL-6 and MYC genes were intact tested by fluorescence in situ hybridization analysis. The patient was diagnosed as IVLBCL and died after 1 month of hospitalization without receiving immunochemotherapy.

CONCLUSIONS

IVLBCL of the liver is a highly rare lymphoma with nonspecific manifestations and dismal prognosis. Full recognition of its clinicopathological features will help to better diagnose this disease.

Role of PI3K/AKT pathway in cancer: the framework of malignant behavior

Given that the PI3K/AKT pathway has manifested its compelling influence on multiple cellular process, we further review the roles of hyperactivation of PI3K/AKT pathway in various human cancers. We state the abnormalities of PI3K/AKT pathway in different cancers, which are closely related with tumorigenesis, proliferation, growth, apoptosis, invasion, metastasis, epithelial-mesenchymal transition, stem-like phenotype, immune microenvironment and drug resistance of cancer cells. In addition, we investigated the current clinical trials of inhibitors against PI3K/AKT pathway in cancers and found that the clinical efficacy of these inhibitors as monotherapy has so far been limited despite of the promising preclinical activity, which means combinations of targeted therapy may achieve better efficacies in cancers. In short, we hope to feature PI3K/AKT pathway in cancers to the clinic and bring the new promising to patients for targeted therapies.

Clinical, pathological and molecular features of plasmablastic lymphoma arising in the gastrointestinal tract: A review and reappraisal

Plasmablastic lymphoma (PBL) is a CD20-negative large B-cell lymphoma with a plasmacytic phenotype and a dismal prognosis, which has been defined as a distinct entity only in the 2008 WHO Classification of Haematopoietic and Lymphoid Tissue and confirmed in the 2017 Edition. Current knowledge of the biological, clinical and prognostic features of PBL is mostly limited, resulting in diagnostic issues, as well as in lack of standard of care and effective therapeutic options. PBL commonly affects the oral cavity of HIV-positive individuals, however the gastrointestinal (GI) tract is the most common extraoral site, and in this location most patients are HIV-negative. In this review, we focus on the clinical, morphological and prognostic features of PBL arising in the GI tract, in order to improve knowledge on this rare, but aggressive disease.

PDGFD induces ibrutinib resistance of diffuse large B‑cell lymphoma through activation of EGFR

Ibrutinib, an FDA approved, orally administered BTK inhibitor, has demonstrated high response rates to diffuse large B-cell lymphoma (DLBCL), however, complete responses are infrequent and acquired resistance to BTK inhibition can emerge. The present study investigated the role of the platelet-derived growth factor D (PDGFD) gene and the ibrutinib resistance of DLBCL in relation to epidermal growth factor receptor (EGFR). Bioinformatics was used to screen and analyze differentially expressed genes (DEGs) in complete response (CR), partial response (PR) and stable disease (SD) in DLBCL treatment with ibrutinib, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to analyze enriched the signaling pathways increasing DEGs. The Search Tool for Interactions of Chemicals database was used to analyze the target genes of ibrutinib. An interaction network of DEGs, disease-related genes and ibrutinib was constructed. The expression of PDGFD in tissues that were resistant or susceptible to DLBCL/ibrutinib was detected via immunohistochemistry (IHC), and the expression of PDGFD in DLBCL/ibrutinib-resistant strains and their parental counterparts were examined via reverse transcription-quantitative PCR and western blot analyses. Subsequently, a drug-resistant cell model of DLBCL/ibrutinib in which PDGFD was silenced was constructed. The apoptosis of the DLBCL/ibrutinib-resistant strains was examined using MTT and flow cytometry assays. EGFR gene expression was then assessed. At the same time, a PDGFD-interfering plasmid and an EGFR overexpression plasmid were transfected into the DLBCL drug-resistant cells (TMD8-ibrutinib, HBL1-ibrutinib) separately or together. MTT was used to measure cell proliferation and changes in the IC₅₀ of ibrutinib. A total of 86 DEGs that increased in the CR, PR and SD tissues were screened, and then evaluated with GO and KEGG. The interaction network diagram showed that there was a regulatory relationship between PDGFD and disease-related genes, and that PDGFD could indirectly target the ibrutinib target gene EGFR, indicating that PDGFD could regulate DLBCL via EGFR. IHC results showed high expression of PDGFD in diffuse large B-cell lymphoma tissues with ibrutinib tolerance. PDGFD expression in ibrutinib-resistant DLBCL cells was higher compared with in parental cells. Following interference with PDGFD expression in ibrutinib-resistant DLBCL cells, the IC₅₀ value of ibrutinib decreased, the rate of apoptosis increased and EGFR expression decreased. In brief, EGFR overexpression can reverse the resistance of DLBCL to ibrutinib via PDGFD interference, and PDGFD induces the resistance of DLBCL to ibrutinib via EGFR.