Role of endoscopic ultrasound‐guided‐fine needle aspiration biopsy in the diagnosis of lymphoma of the pancreas: A clinicopathological study of nine cases

Objective

Endoscopic ultrasound‐guided‐fine needle aspiration (EUS‐FNA) is an established first‐line procedure in the management of solid and cystic pancreatic masses. Lymphoma is an uncommon diagnosis in EUS‐FNA of the pancreas, and it is more common for such a diagnosis to be because of secondary involvement of the pancreas by a lymphoproliferative disorder than for this to represent isolated primary pancreatic lymphoma (PPL). We present the clinical, EUS and cytological features of these lesions.

Material and methods

After obtaining approval from our Institutional Review Board (IRB), nine cases of lymphoma diagnosed on EUS‐FNA at a tertiary care cancer centre over a period of 8 years from 2008 to 2016 were retrieved from our endoscopy and pathology archives. Rapid onsite evaluation (ROSE) was carried out by a trained cytopathologist in all these cases. Cell blocks were available in seven cases, and immunophenotyping was performed on cell blocks using the immunoperoxidase method. Flow cytometry was performed in two cases.

Results

The most frequent site of involvement was the head of the pancreas (n=5, 55.6%). Four out of nine cases were diagnosed as PPL (44.4%). Five cases were diagnosed as lymphoma secondarily involving the pancreas (55.6%). The most frequent diagnosis was diffuse large B‐cell lymphoma (n=6, 66.7%), followed by Hodgkin's lymphoma (n=2, 22.2%) and peripheral T‐cell lymphoma (n=1, 11.1%).

Conclusion

EUS‐FNA in experienced hands is a valuable diagnostic modality, in conjunction with ROSE, immunohistochemistry and flow cytometry, in the diagnosis and sub‐typing of both primary and secondary pancreatic lymphoma.     

Circulating CXCR5+CD4+ T cells assist in the survival and growth of primary diffuse large B cell lymphoma cells through interleukin 10 pathway

Diffuse large B cell lymphoma (DLBCL) is a common and aggressive cancer caused by the malignant transformation of B cells. Although it has been established that the follicular helper T (Tfh) cells play a central role in B cell development, little information is available on their involvement in DLBCL pathogenesis. We studied the role of the peripheral Tfh equivalent, the CXCR5⁺ CD4⁺ T cells, in DLBCL. Data showed that compared to CXCR5^- CD4⁺ T cells, CXCR5⁺ CD4⁺ T cells were significantly more effective at promoting the proliferation as well as inhibiting the apoptosis of primary autologous DLBCL tumor cells. Surprisingly, we found that at equal cell numbers, CXCR5⁺ CD4⁺ T cells in DLBCL patients secreted significantly less interleukin (IL)-21 than CXCR5^- CD4⁺ T cells, while the level of IL-10 secretion was significant elevated in the CXCR5⁺ compartment compared to the CXCR5^- compartment. Neutralization of IL-10 in the primary DLBCL-CXCR5⁺ CD4⁺ T cell coculture compromised the CXCR5⁺ CD4⁺ T cell-mediated pro-tumor effects, in a manner that was dependent on the concentration of anti-IL-10 antibodies. The CXCR5⁺ compartment also contained significantly lower frequencies of cytotoxic CD4⁺ T cells than the CXCR5^- compartment. In conclusion, our investigations discovered a previously unknown pro-tumor role of CXCR5-expressing circulating CD4⁺ T cells, which assisted the survival and proliferation of primary DLBCL cells through IL-10.     

CD4+ T cell-mediated cytotoxicity is associated with MHC class II expression on malignant CD19+ B cells in diffuse large B cell lymphoma

Diffuse large B cell lymphoma (DLBCL) is a common B cell malignancy with approximately 30% of patients present relapsed or refractory disease after first-line therapy. Research of further treatment options is needed. Cytotoxic CD4⁺ T cells express cytolytic molecules and have potential antitumor function. Here, we showed that the CD19⁺ cells from DLBCL patients presented significantly reduced expression of MHC II molecules than those from healthy controls. Three years after the first-line treatment, patients that presented relapsed disease had significantly lower MHC II expression on their CD19⁺ cells than patients who did not show recurrence. Examining cytotoxic CD4⁺ T cells show that DLBCL patients presented significantly elevated frequencies of granzyme A-, granzyme B-, and/or perforin-expressing cytotoxic CD4⁺ T cells. Also, frequency of cytotoxic CD4⁺ T cells in DLBCL patients was positively correlated with the MHC II expression level. Subsequently, the cytotoxic potential of CD4⁺ T cells against autologous CD19⁺ cells was investigated. We found that the cytotoxic potential of CD4⁺ T cells was highest in MHC II-high, intermediate in MHC II-mid, and lowest in MHC II-low patients. The percentage of MHC II-expressing viable CD19⁺ cells presented a significant reduction after longer incubation with cytotoxic CD4⁺ T cells, suggesting that cytotoxic CD4⁺ T cells preferentially eliminated MHC II-expressing CD19⁺ cells. Blocking MHC II on CD19⁺ cells significantly reduced the cytolytic capacity of CD4⁺ T cells. Despite these discoveries, the frequency of cytotoxic CD4⁺ T cells did not predict the clinical outcome of DLBCL patients. Together, these results demonstrated that cytotoxic CD4⁺ T cells presented an MHC II-dependent cytotoxic potential against autologous CD19⁺ cells and could potentially represent a future treatment option for DLBCL.     

CTLA-4在弥漫大B细胞淋巴瘤患者外泌体的表达及初步机制研究

摘要 目的：探讨细胞毒性T淋巴细胞相关抗原4（CTLA-4）在弥漫大B细胞淋巴瘤（DLBCL）患者外泌体的表达及初步机制。方法：2019年6月至2020年11月就诊于本院的DLBCL患者纳入本项研究,分为缓解组和复发组;选取来医院体检的健康志愿者做为对照组;采用试剂盒分离外泌体,CD63抗体包被磁珠结合后,流式细胞术检测CTLA-4+外泌体的比例;流式细胞术检测CD4⁺T细胞、CD8⁺T细胞和调节性T细胞（Treg细胞）的比例。结果：相对于对照组,缓解组DLBCL患者CTLA-4+外泌体的比例升高了37.42%;复发组DLBCL患者CTLA-4+外泌体的比例为6.04%,相对于缓解组,差异具有显著的统计学意义;复发组DLBCL患者CD4/CD8⁺T细胞比值和Treg细胞比例分别为0.85和0.44%,相对于缓解组,差异均具有显著的统计学意义;相关性分析结果显示CTLA-4+外泌体比例与CD4/CD8⁺T细胞比值呈负相关,而与Treg细胞比例呈正相关。结论：CTLA-4+外泌体比例在DLBCL患者显著升高,且与淋巴瘤的治疗效果和抗肿瘤免疫反应均具有紧密的相关性。     

An algorithmic approach to diagnose haematolymphoid neoplasms in effusion by combining morphology,immunohistochemistry and molecular cytogenetics

Objective

There are limited studies of cytology diagnosis of haematopoietic and lymphoid tumours in serosal effusion except for occasional case reports. We would like to demonstrate an algorithmic approach for accurate diagnosis, especially in patients without previous history.

Methods

We reviewed 36 cases of lymphoma diagnosed in serosal effusion following an algorithmic approach. Suspected tumour cells were classified into small, intermediate and large sizes and two characteristic forms of plasmacytoid and Reed Sternberg‐like on smears (step 1), followed by utilising panels of immunohistochemical markers and Epstein‐Barr encoding region in situ hybridisation on cell blocks (step 2). A panel of CD3, CD20 and Ki‐67 formed the basic workup, followed by pertinent batteries of immunostaining. Molecular tests were applied in 22 selected cases by fluorescence in situ hybridisation (step 3).

Results

There were 15 diffuse large B‐cell lymphomas; 12 plasma cell myelomas; two mantle cell lymphomas; one anaplastic large cell lymphoma ALK +; one small lymphocytic lymphoma; one plasmablastic lymphoma; one peripheral T‐cell lymphoma, not otherwise specified, one extranodal NK/T‐cell lymphoma, nasal type and two T‐cell lymphoblastic lymphomas. 14 cases with previous history had complete concordance in immunophenotype between cytology and histology. Another 14 cases were primarily diagnosed in patients with initial symptom of effusion based on immunophenotyping and cytogenetic test in selected cases. Eight cases were diagnosed based on morphology alone.

Conclusion

An algorithmic approach based on morphology and immunohistochemistry is the key to making an accurate diagnosis of haematopoietic and lymphoid tumours in effusion. A molecular test is also important for confirmation and prognostic prediction. We reviewed 36 haematolymphoid neoplasms diagnosed in effusion including 14 cases primarily diagnosed in patients without previous history following an algorithmic approach by combining morphology, immunohistochemistry and molecular cytogenetics.     

VR09 Cell Line: An EBV-Positive Lymphoblastoid Cell Line with In Vivo Characteristics of Diffuse Large B Cell Lymphoma of Activated B-Cell Type

Background

small B-cell neoplasms can show plasmacytic differentiation and may potentially progress to aggressive lymphoma (DLBCL). Epstein-Barr virus (EBV) infection may cause the transformation of malignant cells in vitro.

Design and Method

we established VR09 cell line with plasmacytic differentiation, obtained from a case of atypical, non-CLL B-cell chronic lymphoproliferative disease with plasmacytic features. We used flow cytometry, immunohistochemistry, polymerase chain reaction, cytogenetic analysis and florescence in situ hybridization in the attempt at thoroughly characterizing the cell line. We showed VR09 tumorigenic potential in vivo, leading to the development of activated DLBCL with plasmacytic features.

Results

VR09 cells displayed plasmacytic appearance and grew as spherical tumors when inoculated subcutaneously into immunodeficient Rag2^−/− γ-chain^−/− mice. VR09 cell line and tumors displayed the phenotype of activated stage of B cell maturation, with secretory differentiation (CD19+ CD20+ CD79a+ CD79b+/− CD138+ cyclin D1- Ki67 80% IgM+ IgD+ MUM1+ MNDA+ CD10- CD22+ CD23+ CD43+ K+, λ- Bcl2+ Bcl6-) and they presented episomal EBV genome, chromosome 12 trisomy, lack of c-MYC rearrangement and Myd88 gene mutation, presence of somatic hypermutation in the VH region, and wild-type p53.

Conclusion

This new EBV-positive cell line may be useful to further characterize in vivo activated DLBCL with plasmacytic features.     

Establishment and characterization of a novel ‘double‐hit’ follicular lymphoma cell line,FL‐SJC

About 5 per cent of follicular lymphoma (FL) cases are double‐hit (DH) lymphomas. Double‐hit follicular lymphoma (DHFL) cell lines can improve our understanding and drug development on FL. But there are only few DHFL cell lines. Here, we established a new MYC/BCL2 DHFL cell line, FL‐SJC. The cells were obtained from the hydrothorax of a patient with MYC/BCL2 DHFL and cultured for 140 passages in vitro. FL‐SJC cells demonstrated CD19⁺⁺, CD20⁺, CD22⁺⁺, HLA‐DR⁺, CD10⁺, CD38⁺, Lambda⁺ CD23^‐, CD5^‐ and Kappa^‐. The chromosome karyotypic analysis confirmed the co‐existence of t(8;22)(q24;q11) and t(14;18)(q32;q21), as well as additional abnormalities involving chromosomes 2 and 3. Fluorescence in situ hybridization analysis (FISH) showed IGH/BCL2 fusion gene and the MYC rearrangement. In addition, the FL‐SJC cells displayed KMT2D/MLL2 and CREBBP gene mutations. After subcutaneous inoculation of FL‐SJC cells, the SCID mice developed solid tumour masses within 6‐8 weeks. FL‐SJC cells were proven to be free of Epstein‐Barr (EB) virus infection and be multidrug‐resistant. In a conclusion, the FL‐SJC cell line has been identified as a novel MYC/BCL2 double‐hit follicular lymphoma that can be used as a potentially available tool for the clinical and basic research, together with the drug development for MYC/BCL2 DHFL.     

Resveratrol suppresses constitutive activation of AKT via generation of ROS and induces apoptosis in diffuse large B cell lymphoma cell lines

Background

We have recently shown that deregulation PI3-kinase/AKT survival pathway plays an important role in pathogenesis of diffuse large B cell lymphoma (DLBCL). In an attempt to identify newer therapeutic agents, we investigated the role of Resveratrol (trans-3,4′, 5-trihydroxystilbene), a naturally occurring polyphenolic compound on a panel of diffuse large B-cell lymphoma (DLBCL) cells in causing inhibition of cell viability and inducing apoptosis.

Methodology/Principal Findings

We investigated the action of Resveratrol on DLBCL cells and found that Resveratrol inhibited cell viability and induced apoptosis by inhibition of constitutively activated AKT and its downstream targets via generation of reactive oxygen species (ROS). Simultaneously, Resveratrol treatment of DLBCL cell lines also caused ROS dependent upregulation of DR5; and interestingly, co-treatment of DLBCL with sub-toxic doses of TRAIL and Resveratrol synergistically induced apoptosis via utilizing DR5, on the other hand, gene silencing of DR5 abolished this effect.

Conclusion/Significance

Altogether, these data suggest that Resveratrol acts as a suppressor of AKT/PKB pathway leading to apoptosis via generation of ROS and at the same time primes DLBCL cells via up-regulation of DR5 to TRAIL-mediated apoptosis. These data raise the possibility that Resveratrol may have a future therapeutic role in DLBCL and possibly other malignancies with constitutive activation of the AKT/PKB pathway.     

Study of Regulatory T-Cells in Patients with Gastric Malt Lymphoma: Influence on Treatment Response and Outcome

Purpose

FOXP3+ regulatory T cells (Treg) play an essential role in modulating host responses to tumors and infections. The role of these cells in the pathogenesis of MALT lymphomas remains unknown. The aims of the study were to quantify the number of infiltrating FOXP3+ and CD3+ cells in patients with gastric MALT lymphoma at diagnosis and to study kinetics of these cells and CD20+ tumor cells after treatment and during long-term follow-up.

Methods

FOXP3+, CD3+ and CD20+ cells were analyzed by immunohistochemistry and the number of cells was quantified using a micrometric ocular. Samples of 35 patients with gastric MALT lymphoma at diagnosis and after treatment were included. Diagnostic samples were compared to 19 cases of chronic gastritis and diffuse large B-cell lymphoma (DLBCL) of the stomach.

Results

The median number of FOXP3+ infiltrating cells was higher (27 cells/cm²) in gastric MALT patients than in DLBCL (10 cells; p = 0.162) but similar to chronic gastritis (20 cells; p = 0.605). No characteristic or specific distribution pattern of infiltrating FOXP3+ cells was found. Gastric MALT lymphoma patients responding to bacterial eradication therapy had higher number of FOXP3+ cells at study entry. Kinetics of both infiltrating FOXP3+ cells and tumor CD20+ cells were strongly dependent on the treatment administered.

Discussion

Gastric MALT lymphomas have a number of Treg cells more similar to chronic gastritis than to DLBCL. Patients with higher number of tumor infiltrating FOXP3+ cells at study entry seem to have better response to antibiotics. Kinetics of Treg and tumor cells are influenced by type of treatment.     

Immunological microenvironment gene expression in patients with diffuse large B cell non Hodgkin lymphoma

BackgroundNon Hodgkin lymphoma (NHL) is one of the immune system cancers. The occurrence and progression of malignant lymphomas depends on cellular pathways deregulation. Understanding the relationship between the immune system at the genetic level and malignant transformation is critical to reach its etiology.ObjectiveThe aim of this work is to evaluate the expression of five immune related genes (PD-1, FOXP3, GrA, GrB and CD11c) in patients with diffuse large B cell non Hodgkin lymphoma (DLBCL).Materials and methodsThis study was conducted on fifty patients with DLBCL and fifty sex and age matched apparently healthy subjects. The participants were subjected to these laboratory investigations: complete blood count, serum lactate dehydrogenase and β2microglobulin (β₂M) levels and determination of PD-1, FOXP3, GrA, GrB and CD11c gene expressions.ResultsThe results of this study revealed that PD-1, FOXP3, GrA, GrB and CD11c gene expressions were significantly increased in DLBCL patients.ConclusionPatients with DLBCL have variablePD-1, FOXP3,GrA, GrB and CD11cgene expressions levels, which are correlated with the overall survival (OS) indicating that they can be good predictors of outcome in these patients.     

Diverse Hematological Malignancies Including Hodgkin-Like Lymphomas Develop in Chimeric MHC Class II Transgenic Mice

A chimeric HLA-DR4-H2-E (DR4) homozygous transgenic mouse line spontaneously develops diverse hematological malignancies with high frequency (70%). The majority of malignancies were distributed equally between T and B cell neoplasms and included lymphoblastic T cell lymphoma (LTCL), lymphoblastic B cell lymphoma (LBCL), diffuse large B cell lymphoma (DLBCL), the histiocyte/T cell rich variant of DLBCL (DLBCL-HA/T cell rich DLBCL), splenic marginal zone lymphoma (SMZL), follicular B cell lymphoma (FBL) and plasmacytoma (PCT). Most of these neoplasms were highly similar to human diseases. Also, some non-lymphoid malignancies such as acute myeloid leukemia (AML) and histiocytic sarcoma were found. Interestingly, composite lymphomas, including Hodgkin-like lymphomas, were also detected that had CD30⁺ Hodgkin/Reed-Sternberg (H/RS)-like cells, representing a tumor type not previously described in mice. Analysis of microdissected H/RS-like cells revealed their origin as germinal center B cells bearing somatic hypermutations and, in some instances, crippled mutations, as described for human Hodgkin lymphoma (HL). Transgene integration in an oncogene was excluded as an exclusive driving force of tumorigenesis and age-related lymphoma development suggests a multi-step process. Thus, this DR4 line is a useful model to investigate common molecular mechanisms that may contribute to important neoplastic diseases in man.     

Endogenous neurotrophins and Trk signaling in diffuse large B cell lymphoma cell lines are involved in sensitivity to rituximab-induced apoptosis

Background

Diffuse large B-cell lymphoma (DLBCL) is a common and often fatal malignancy. Immunochemotherapy, a combination of rituximab to standard chemotherapy, has resulted in improved survival. However a substantial proportion of patients still fail to reach sustained remission. We have previously demonstrated that autocrine brain-derived neurotrophic factor (BDNF) production plays a function in human B cell survival, at least partly via sortilin expression. As neurotrophin receptor (Trks) signaling involved activation of survival pathways that are inhibited by rituximab, we speculated that neurotrophins may provide additional support for tumour cell survival and therapeutic resistance in DLBCL.

Methodology/Principal Findings

In the present study, we used two DLBCL cell lines, SUDHL4 and SUDHL6, known to be respectively less and more sensitive to rituximab. We found by RT-PCR, western blotting, cytometry and confocal microscopy that both cell lines expressed, in normal culture conditions, BDNF and to a lesser extent NGF, as well as truncated TrkB and p75^NTR/sortilin death neurotrophin receptors. Furthermore, BDNF secretion was detected in cell supernatants. NGF and BDNF production and Trk receptor expression, including TrkA, are regulated by apoptotic conditions (serum deprivation or rituximab exposure). Indeed, we show for the first time that rituximab exposure of DLBCL cell lines induces NGF secretion and that differences in rituximab sensitivity are associated with differential expression patterns of neurotrophins and their receptors (TrkA). Finally, these cells are sensitive to the Trk-inhibitor, K252a, as shown by the induction of apoptosis. Furthermore, K252a exhibits additive cytotoxic effects with rituximab.

Conclusions/Significance

Collectively, these data strongly suggest that a neurotrophin axis, such NGF/TrkA pathway, may contribute to malignant cell survival and rituximab resistance in DLBCL.     

Autonomous growth potential of leukemia blast cells is associated with poor prognosis in human acute leukemias

Background

Anaplastic lymphoma kinase-positive diffuse large B-cell lymphoma (ALK-DLBCL) is a rare lymphoma with several clinicopathological differences from ALK-positive anaplastic large cell lymphoma (ALCL). The latest WHO classification of lymphomas recognizes ALK-DLBCL as a separate entity.

Methods

A comprehensive comparison was made between the clinical and pathological features of the 4 cases reported and those found in an extensive literature search using MEDLINE through December 2008.

Results

In our series, three cases were adults and one was pediatric. Two cases had primary extranodal disease (multifocal bone and right nasal fossa). Stages were I (n = 1), II (n = 1), III (n = 1) and IV (n = 1). Two cases had increased LDH levels and three reported B symptoms. IPI scores were 0 (n = 1), 2 (n = 2) and 3 (n = 1). All cases exhibited plasmablastic morphology. By immunohistochemistry, cases were positive for cytoplasmic ALK, MUM1, CD45, and EMA; they marked negative for CD3, CD30 and CD20. Studies for EBV and HHV-8 were negative. The survival for the patients with stage I, II, III and IV were 13, 62, 72 and 11 months, respectively.

Conclusion

ALK-DLBCL is a distinct variant of DLBCL with plasmacytic differentiation, which is characterized by a bimodal age incidence curve, primarily nodal involvement, plasmablastic morphology, lack of expression of CD20, aggressive behavior and poor response to standard therapies, although some cases can have prolonged survival as the cases reported in this study. ALK-DLBCL does not seem associated to immunosuppression or the presence of EBV or HHV8. Further prospective studies are needed to optimize therapies for this entity.     

Combined treatment of rituximab,idarubicin, dexamethasone,cytarabine, methotrexate with radiotherapy for primary central nervous system lymphoma

The overall response rates and long‐term survival of primary central nervous system lymphoma (PCNSL) are still significantly inferior to the results achieved in similar subtypes of extranodal non‐Hodgkin's lymphoma. It is clearly necessary to investigate new therapeutic methods on PCNSL. We encountered three patients histologically documented PCNSL as diffuse large B‐cell lymphoma (DLBCL). They were treated with R‐IDARAM which comprised rituximab, idarubicin, dexamethasone, cytarabine and methotrexate. Patient 1 received stereotactic brachytherapy (SBT) prior to chemotherapy performed with iodine‐125 seeds (cumulative therapeutic dose 50 Gy). After six cycles of R‐IDARAM at 3‐weekly intervals, radiotherapy was applied at a dosage of 2000–4000 cGy in conventional schedule (180 or 200 cGy/day) to whole brain or spinal cord in all patients. Complete remission (CR) was achieved after first two cycles of R‐IDARAM in all patients. All three patients remained in CR at the time of this report with a median duration of follow‐up of 23 months (ranging from 13 to 41 months). Three patients have been alive for 41, 13, 16 months respectively until now. The patient with the longest survival time was the one given SBT prior to chemotherapy. This study suggests that R‐IDARAM combining with radiotherapy maybe a high effective regimen in PCNSL patients especially those with primary central nervous system DLBCL. A comprehensive treatment combining internal radiotherapy by SBT, modified R‐IDARAM and followed reduced external radiotherapy may be a new treatment concept for PCNSL with higher efficiency and lower toxicity.     

Anti‐Helicobacter pylori therapy in localized gastric mucosa‐associated lymphoid tissue lymphoma: A prospective,nationwide, multicenter study in Japan

Background

Helicobacter pylori eradication therapy was approved in Japan for the first‐line, standard treatment of H. pylori‐positive gastric mucosa‐associated lymphoid tissue (MALT) lymphoma. Although several retrospective studies or small‐scale single‐center studies have been reported, a prospective, large‐scale, nationwide, multicenter study has not been reported from Japan.

Materials and Methods

We conducted a prospective, nationwide, multicenter study to evaluate the clinical efficacy of rabeprazole‐based triple H. pylori eradication therapy for patients with localized gastric MALT lymphoma in practice‐based clinical trial. A total of 108 H. pylori‐positive patients with stage I/II₁ gastric MALT lymphoma underwent H. pylori eradication therapy. The primary endpoints were complete remission (CR) rate and the rate of transfer to secondary treatment. The secondary endpoints were CR maintenance duration and overall survival (OS).

Results

CR of lymphoma was achieved in 84 of 97 patients (86.6%), during the period 2.0‐44.7 months (median, 5.3 months) after starting H. pylori eradication treatment. CR was maintained in 77 of 81 patients (95.1%) for 0.4‐53.2 months (median, 33.1 months). Secondary treatments (radiotherapy, rituximab, or gastrectomy) for gastric MALT lymphoma were needed in 10 of the 97 patients (10.31%). During follow‐up, OS rate was 96.9% (94/97) and the causes of 3 deaths were not related to lymphoma.

Conclusions

Rabeprazole‐based H. pylori eradication therapy demonstrated a high CR rate, long CR maintenance, and a good OS for patients with localized gastric MALT lymphoma in this prospective, practice‐based, multicenter study.     

Long non‐coding RNA SNHG16 promotes proliferation and inhibits apoptosis of diffuse large B‐cell lymphoma cells by targeting miR‐497‐5p/PIM1 axis

The aberrant expression and dysfunction of long non‐coding RNAs (lncRNAs) have been identified as critical factors governing the initiation and progression of different human cancers, including diffuse large B‐cell lymphoma (DLBCL). LncRNA small nucleolar RNA host gene 16 (SNHG16) has been recognized as a tumour‐promoting factor in various types of cancer. However, the biological role of SNHG16 and its underlying mechanism are still unknown in DLBCL. Here we disclosed that SNHG16 was overexpressed in DLBCL tissues and the derived cell lines. SNHG16 knockdown significantly suppressed cell proliferation and cell cycle progression, and it induced apoptosis of DLBCL cells in vitro. Furthermore, silencing of SNHG16 markedly repressed in vivo growth of OCI‐LY7 cells. Mechanistically, SNHG16 directly interacted with miR‐497‐5p by acting as a competing endogenous RNA (ceRNA) and inversely regulated the abundance of miR‐497‐5p in DLBCL cells. Moreover, the proto‐oncogene proviral integration site for Moloney murine leukaemia virus 1 (PIM1) was identified as a novel direct target of miR‐497‐5p. SNHG16 overexpression rescued miR‐497‐5p‐induced down‐regulation of PIM1 in DLBCL cells. Importantly, restoration of PIM1 expression reversed SNHG16 knockdown‐induced inhibition of proliferation, G0/G1 phase arrest and apoptosis of OCI‐LY7 cells. Our study suggests that the SNHG16/miR‐497‐5p/PIM1 axis may provide promising therapeutic targets for DLBCL progression.     

CUL4B regulates autophagy via JNK signaling in diffuse large B-cell lymphoma

Aberrant expression of CUL4B was identified in various types of solid cancers. Cumulative evidences support the oncogenic role of CUL4B in cancers, including regulation of cell proliferation and signal transduction. However, its clinical value and potential pathogenic mechanism in diffuse large B-cell lymphoma (DLBCL) have not been described previously. Therefore, we hypothesize that overexpressed CUL4B may contribute to the pathogenesis of DLBCL. The aim of this study is to assess the expression and the biological function of CUL4B in DLBCL progression. In our study, CUL4B overexpression was observed in DLBCL tissues, and its upregulation was closely associated with poor prognosis in patients. Furthermore, the functional roles of CUL4B was detected both in vitro and in vivo. We demonstrated that silencing CUL4B could not only induce cell proliferation inhibition, cell cycle arrest, and motility attenuation of DLBCL cells in vitro, but also decrease tumor growth in DLBCL xenografts mice. In addition, we identi?ed that CUL4B may act as a potent inductor of JNK phosphorylation in regulation of autophagy. Our findings demonstrated a significant role of CUL4B in the development and progression of DLBCL. CUL4B may act as a useful biomarker and a novel therapeutic target in DLBCL.     

Correlations between Functional Imaging Markers Derived from PET/CT and Diffusion-Weighted MRI in Diffuse Large B-Cell Lymphoma and Follicular Lymphoma

Objectives

To investigate the correlations between functional imaging markers derived from positron emission tomography/computed tomography (PET/CT) and diffusion-weighted magnetic resonance imaging (DWI) in diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL). Further to compare the usefulness of these tumor markers in differentiating diagnosis of the two common types of Non-Hodgkin''s lymphoma (NHL).

Materials and Methods

Thirty-four consecutive pre-therapy adult patients with proven NHL (23 DLBCL and 11 FL) underwent PET/CT and MRI examinations and laboratory tests. The maximum standardized uptake value (SUV_max), metabolic tumor volume (MTV), and metabolic tumor burden (MTB) were determined from the PET/CT images. DWI was performed in addition to conventional MRI sequences using two b values (0 and 800 s/mm²). The minimum and mean apparent diffusion coefficient (ADC_min and ADC_mean) were measured on the parametric ADC maps.

Results

The SUV_max correlated inversely with the ADC_min (r = −0.35, p<0.05). The ADC_min, ADC_mean, serum thymidine kinase (TK), Beta 2-microglobulin (B2m), lactate dehydrogenase (LD), and C-reactive protein (CRP) correlated with both whole-body MTV and whole-body MTB (p<0.05 or 0.01). The SUV_max, TK, LD, and CRP were significantly higher in the DLBCL group than in the FL group. Receiver operating characteristic curve analysis showed that they were reasonable predictors in differentiating DLBCL from FL.

Conclusions

The functional imaging markers determined from PET/CT and DWI are associated, and the SUV_max is superior to the ADC_min in differentiating DLBCL from FL. All the measured serum markers are associated with functional imaging markers. Serum LD, TK, and CRP are useful in differentiating DLBCL from FL.     

Soluble CXCL16 promotes TNF‐α‐induced apoptosis in DLBCL via the AMAD10‐NF‐κB regulatory feedback loop

We had previously identified that the co‐expression of transmembrane CXCL16 (TM‐CXCL16) and its receptor CXCR6 is an independent risk factor for poor survival in patients with diffuse large B‐cell lymphoma (DLBCL). However, the impact of the soluble form of CXCL16 (sCXCL16) on the pathogenesis of DLBCL remains unknown. In the present study, the synergistic effect of sCXCL16 and tumor necrosis factor α (TNF‐α) on apoptosis in DLBCL cell lines (OCI‐LY8 and OCI‐LY10) was investigated in vitro. sCXCL16 reinforced TNF‐α‐mediated inhibition of DLBCL cell proliferation, as determined by the cell counting kit‐8 assay. The results of annexin V staining showed that sCXCL16 enhanced TNF‐α‐induced apoptosis in OCI‐LY8 and OCI‐LY10 cells through a death receptor‐caspase signaling pathway. The results of gene microarray suggested a significant upregulation of differentially expressed genes in the TNF signaling pathway. sCXCL16 increased the concentration of extracellular TNF‐α by binding to CXCR6 to activate the nuclear factor‐κB (NF‐κB) signaling pathway. TNF‐α also induced the secretion of sCXCL16 by increasing the expression of ADAM10, which is known to cleave TM‐CXCL16 to yield sCXCL16. Moreover, bioinformatics analysis revealed that elevated TNF‐α and ADAM10 expression levels in tumor tissues predicted better survival in patients with DLBCL. Thus, our study suggests that sCXCL16 enhances TNF‐α‐induced apoptosis of DLBCL cells, which may involve a positive feedback loop consisting of TNF‐α, ADAM10, sCXCL16, and members of the NF‐κB pathway. sCXCL16 and TNF‐α may be used as prognostic markers in the clinic, and their combinational use is a promising approach in the context of DLBCL therapy.