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Nutritional status is a determining factor for growth during development and homeostatic maintenance in adulthood. In the context of muscle, growth hormone (GH) coordinates growth with nutritional status; however, the detailed mechanisms remain to be fully elucidated. Here, we show that the transcriptional repressor B cell lymphoma 6 (BCL6) maintains muscle mass by sustaining GH action. Muscle-specific genetic deletion of BCL6 at either perinatal or adult stages profoundly reduces muscle mass and compromises muscle strength. Conversely, muscle-directed viral overexpression of BCL6 significantly reverses the loss of muscle mass and strength. Mechanistically, we show that BCL6 transcriptionally represses the suppressor of cytokine signaling 2 to sustain the anabolic actions of GH in muscle. Additionally, we find that GH itself transcriptionally inhibits BCL6 through the Janus kinase and signal transducer and activator of transcription 5 (JAK/STAT5) pathway. Supporting the physiologic relevance of this feedback regulation, we show the coordinated suppression of muscle Bcl6 expression with the induction of GH in the fasted state. These findings reveal the complexity of the feedback controls modulating GH signaling and identify BCL6 as a key homeostatic regulator coordinating muscle mass with nutrient availability. Moreover, these studies open avenues for targeted therapeutic strategies to combat muscle-wasting conditions. [ABSTRACT FROM AUTHOR]

Large B‐cell lymphomas (LBLs) comprise a genetically heterogeneous group of clinically aggressive non‐Hodgkin lymphomas, frequently exhibiting overlapping features with diffuse large B‐cell lymphoma and Burkitt's lymphoma. We report a case of a 24‐year‐old, previously healthy male with a classical clinical presentation of acute appendicitis. The pathologic examination discovered a large B‐cell lymphoma with MYC and BCL6 rearrangements in the excised appendix. The patient was assigned Stage IEA, IPI = 0 and received chemotherapy. This case depicts a very uncommon occurrence of fully localized LBL in a patient of an unusually young age and clinical presentation for this type of lymphoma. [ABSTRACT FROM AUTHOR]

B cell lymphoma 6 (BCL6) is a conserved multi-domain protein that functions principally as a transcriptional repressor. This protein regulates many pivotal aspects of immune cell development and function. BCL6 is critical for germinal center (GC) formation and the development of high-affinity antibodies, with key roles in the generation and function of GC B cells, follicular helper T (Tfh) cells, follicular regulatory T (Tfr) cells, and various immune memory cells. BCL6 also controls macrophage production and function as well as performing a myriad of additional roles outside of the immune system. Many of these regulatory functions are conserved throughout evolution. The BCL6 gene is also important in human oncology, particularly in diffuse large B cell lymphoma (DLBCL) and follicular lymphoma (FL), but also extending to many in other cancers, including a unique role in resistance to a variety of therapies, which collectively make BCL6 inhibitors highly sought-after. [ABSTRACT FROM AUTHOR]

Several reports of concurrent MYC , BCL2 , BCL6 , and CCND1 rearrangements in high-grade B-cell lymphoma (HGBL) have been recently described. Herein, we aimed to delineate the scope of this entity through a review of HGBL with a "quadruple-hit" genetic profile identified at our institution. We performed a retrospective review (2015-2023) at our institution of B-cell lymphoma (BCL) cases that were evaluated with concurrent MYC , BCL2 , and BCL6 break-apart and IGH::MYC and IGH::CCND1 dual-color dual-fusion fluorescence in situ hybridization studies. Of 203 cases meeting inclusion criteria, 2 (1%) with a quadruple-hit genetic profile were identified. Case 1 represented a 59-year-old female with widespread lymphadenopathy and a diagnosis of HGBL who exhibited primary refractoriness to dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab (DA-EPOCH-R) chemotherapy. Case 2 represented a 58-year-old male with mediastinal and abdominal lymphadenopathy and a diagnosis of large BCL who died from disease after 1 cycle of DA-EPOCH-R chemotherapy. Similarly, a literature review of 7 previously reported cases of HGBL with a quadruple-hit profile also demonstrated aggressive disease behavior. Our study adds 2 new cases to the rarely encountered quadruple-hit HGBL, and a brief meta-analysis of the 9 available cases indicates aggressive disease behavior conferred by this constellation of genetic events. [ABSTRACT FROM AUTHOR]

MYC-rearranged high-grade B-cell lymphoma (HGBCL) patients with concurrent BCL2 rearrangements (HGBCLMYC/BCL2) often have a poor prognosis with standard chemoimmunotherapy and may benefit from more intensified regimens. Conventional fluorescence in situ hybridization (FISH) is the gold standard for detecting rearrangements, but it has several limitations. This study compared DNA and RNA-sequencing with FISH to detect clinically relevant rearrangements in HGBCL. Archived formalin-fixed, paraffin-embedded samples from 34 patients who underwent FISH testing were analyzed using targeted DNA and RNA-sequencing. DNA and RNA-sequencing identified six and five out of the 12 MYC rearrangements detected by FISH, 10 and 6 out of 10 FISH-detectable BCL2 rearrangements, and 13 and 10 out of the 18 FISH-detectable BCL6 rearrangements. When combining DNA and RNA-sequencing (integrated NGS), the sensitivity for detecting MYC, BCL2, and BCL6 rearrangements was 58.3%, 100%, and 73.7%, respectively. Both DNA and RNA-sequencing detected the EIF4A2::BCL6 fusion missed by FISH. FISH identified 12 HGBCL-MYC/BCL2 out of 34 cases, while the integrated NGS strategy identified 7 cases, with 5 cases showing discordant results (41.7%). Additionally, patients with DLBCL/HGBCL-MYC/BCL2 had significantly shorter overall survival than other patients. Our results suggest that an integrated NGS strategy should not replace FISH or be routinely used in the workup to detect the clinically relevant rearrangements in HGBCL. It may serve as a complement to FISH testing when FISH shows negative results. [ABSTRACT FROM AUTHOR]

Mantle cell lymphoma (MCL) is a type of non-Hodgkin lymphoma (NHL) characterized by a hallmark translocation of t (11; 14). CD10 negativity has been used to differentiate MCL from other NHL types; however, recently, there has been an increase in the number of reported cases of CD10-positive MCL. This warrants further investigation into this rarer immunophenotype and its clinical significance. BCL6, which is a master transcription factor for the regulation of cell proliferation and key oncogene in B cell lymphomagenesis, has been reported to have co-expression with CD10 in MCL. The clinical significance of this aberrant antigen expression remains unknown. We conducted a systematic review by searching four databases and selected five retrospective analyses and five case series. Two survival analyses were conducted to determine if BCL6 positivity conferred a survival difference: 1. BCL6+ vs. BCL6- MCL. 2. BCL6+/CD10+ vs. BCL6-/CD10+ MCL. Correlation analysis was conducted to determine if BCL6 positivity correlated with the Ki67 proliferation index (PI). Overall survival (OS) rates were performed by the Kaplan-Meier method and log-rank test. Our analyses revealed that BCL6+ MCL had significantly shorter overall survival (median OS: 14 months vs. 43 months; p = 0.01), BCL6+/CD10+ MCL had an inferior outcome vs. BCL6+/CD10- MCL (median OS: 20 months vs. 55 months p = 0.1828), BCL6+ MCL had significantly higher percentages of Ki67% (Ki67% difference: 24.29; p = 0.0094), and BCL6 positivity had a positive correlation with CD10+ status with an odds ratio 5.11 (2.49, 10.46; p = 0.0000286). Our analysis showed that BCL6 expression is correlated with CD10 positivity in MCL, and BCL6 expression demonstrated an inferior overall survival. The higher Ki67 PI in BCL6+ MCL compared to BCL6- MCL further supports the idea that the BCL6+ immunophenotype may have prognostic value in MCL. MCL management should consider incorporating prognostic scoring systems adjusted for BCL6 expression. Targeted therapies against BCL6 may offer potential therapeutic options for managing MCL with aberrant immunophenotypes.

MYC, BCL2, and BCL6 rearrangements are clinically important events of diffuse large B-cell lymphoma (DLBCL). The ability and clinical value of targeted next-generation sequencing (NGS) in the detection of these rearrangements in DLBCL have not been fully determined. We performed targeted NGS (481-gene-panel) and break-apart FISH of MYC, BCL2, and BCL6 gene regions in 233 DLBCL cases. We identified 88 rearrangements (16 MYC; 20 BCL2; 52 BCL6) using NGS and 96 rearrangements (28 MYC; 20 BCL2; 65 BCL6) using FISH. The consistency rates between FISH and targeted NGS for the detection of MYC, BCL2, and BCL6 rearrangements were 93%, 97%, and 89%, respectively. FISH-cryptic rearrangements (NGS +/FISH-) were detected in 7 cases (1 MYC; 3 BCL2; 2 BCL6; 1 MYC::BCL6), mainly caused by small chromosomal insertions and inversions. NGS-/FISH+ were detected in 38 cases (14 MYC; 4 BCL2; 20 BCL6). To clarify the cause of the inconsistencies, we selected 17 from the NGS-/FISH+ rearrangements for further whole genome sequencing (WGS), and all 17 rearrangements were detected with break points by WGS. These break points were all located outside the region covered by the probe of targeted NGS, and most (16/17) were located in the intergenic region. These results indicated that targeted NGS is a powerful clinical diagnostics tool for comprehensive MYC, BCL2, and BCL6 rearrangement detection. Compared to FISH, it has advantages in describing the break point distribution, identifying uncharacterized partners, and detecting FISH-cryptic rearrangements. However, the lack of high-sensitivity caused by insufficient probe coverage is the main limitation of the current technology. [ABSTRACT FROM AUTHOR]

Background: Artificial intelligence in medicine is a field that is rapidly evolving. Machine learning and deep learning are used to improve disease identification and diagnosis, personalize disease treatment, analyze medical images, evaluate clinical trials, and speed drug development. Methods: First, relevant aspects of AI are revised in a comprehensive manner, including the classification of hematopoietic neoplasms, types of AI, applications in medicine and hematological neoplasia, generative pre-trained transformers (GPTs), and the architecture and interpretation of feedforward neural net-works (multilayer perceptron). Second, a series of 233 diffuse large B-cell lymphoma (DLBCL) patients treated with rituximab-CHOP from the Lymphoma/Leukemia Molecular Profiling Project (LLMPP) was analyzed. Results: Using conventional statistics, the high expression of MYC and BCL2 was associated with poor survival, but high BCL6 was associated with a favorable overall survival of the patients. Then, a neural network predicted MYC, BCL2, and BCL6 with high accuracy using a pan-cancer panel of 758 genes of immuno-oncology and translational research that includes clinically relevant actionable genes and pathways. A comparable analysis was performed using gene set enrichment analysis (GSEA). Conclusions: The mathematical way in which neural networks reach conclusions has been considered a black box, but a careful understanding and evaluation of the architectural design allows us to interpret the results logically. In diffuse large B-cell lymphoma, neural networks are a plausible data analysis approach. [ABSTRACT FROM AUTHOR]

Lymphoma is one of the most common malignant neoplasms in cats. Historically, most feline lymphomas were associated with feline leukaemia virus infection, but due to routine vaccination against the virus, especially in developed countries, feline leukaemia virus‐associated cases are dramatically reduced in numbers. More recently, the most common lymphoma in cats is intestinal lymphoma, with most common type being the enteropathy‐associated T‐cell lymphomas. Follicular lymphoma is recognised in cats, but is very uncommon. Primary colorectal follicular lymphoma is rare in humans and has been reported in three dogs. In this case report, we describe a primary colorectal lymphoma with histological and immunohistochemical features of a follicular lymphoma in a Savannah cat. To the authors' knowledge, this is the first case report of a primary colorectal follicular lymphoma in cats, and differential diagnosis of tumours in the colorectal area in cats should include follicular lymphoma. [ABSTRACT FROM AUTHOR]

Background and Aim: c-MYC is a potent transcription factor involved in several cellular processes, and is overexpressed in many cancers, including non-Hodgkin lymphoma (NHL). The most common subtype of NHL is diffuse large B-cell lymphoma (DLBCL). DLBCL tumors expressing both the c-MYC and BCL2 proteins, i.e. double expressor (DE), also triple expressors (TE) expressing BCL6 in addition to c-MYC and BCL2, are all more aggressive and refractory to treatment. Our study aims to investigate auxiliary immunohistochemical tests (IHC) not routinely used, namely c-MYC, BCL2 and BCL6, seeking a better prognostic testing protocol for DLBCL patients. Materials and Methods: Forty-one formalin-fixed paraffin-embedded (FFPE) DLBCL samples were collected retrospectively from the pathology laboratory at Al-Assad University Hospital after approval from the ethics committee at Damascus University. Clinical data was obtained from patients records in regards to progression-free survival (PFS) and other parameters. Slides were microtomed from each FFPE sample and used to perform IHC tests of the c-MYC, BCL2 and BCL6 oncoproteins. Fisher’s exact test was used to study the independence of protein IHC results in relation to one another and compared with PFS. Results: Statistical analysis of the c-MYC overexpression and double expressor status showed no correlation (P>0.05) with PFS in DLBCL patients. Whereas, when BCL6 IHC results were analyzed, BCL6 positivity and triple expressor status showed a significant association (P

Background: Diffuse large B cell lymphoma (DLBCL) is the most prevalent subtype of non-Hodgkin's lymphoma, characterized by remarkable molecular heterogeneity. This study evaluates the prevalence of MYC, BCL2, and BCL6 gene rearrangements among Iranian DLBCL patients.Method: This historical cohort study encompassed 152 patients drawn from six reference hospitals who participated in the research. Interphase dual-color break-apart fluorescence in situ hybridization (FISH) was applied to formalin-fixed paraffin-embedded DLBCL specimens categorized as "not otherwise specified" alongside 20 normal controls. Survival data was analyzed using the Kaplan-Meier method and the Log-Rank test.Results: Among the patients, 7 (4.8%), 4 (2.9%), and 15 (10.2%) exhibited MYC, BCL2, and BCL6 rearrangements, respectively. Additionally, 1.5% of the patients demonstrated double-hit (DH) characteristics with both MYC and BCL2 rearrangements, while no triple rearrangements were observed. The presence of rearrangements appeared to be independent of clinicopathological variables. Patients with rearrangements experienced reduced survival durations, with reductions of 26.6, 31.2, 9.1, and 34.2 months for MYC, BCL2, BCL6-rearranged, and DH tumors, respectively (P > 0.05). Adverse prognosis was associated with age, activated B-cell-like phenotype, disease stage, B symptoms, lactate dehydrogenase levels, and risk grouping according to the National Comprehensive Cancer Network (NCCN) International Prognostic Index.Conclusion: DLBCL cases featuring MYC, BCL2, and/or BCL6 translocations are relatively rare. Patients harboring these rearrangements tend to exhibit aggressive disease progression with shortened overall survival. However, these differences did not reach statistical significance, necessitating further research to validate the incorporation of such tests into the routine workup of DLBCL patients.

Diffuse large B-cell lymphoma (DLBCL) accounts for half of non-Hodgkin lymphoma cases in people living with human immunodeficiency syndrome (PLWH). The interplay of viremia, immune dysregulation and co-infection with oncogenic viruses play a role in pathogenesis of DLBCL in PLWH (HIV-DLBCL). This scoping review aimed to describe the molecular landscape of HIV-DLBCL, investigate the impact of biomarker on clinical outcomes and describe technologies used to characterise HIV-DLBCL. Thirty-two papers published between 2001 and 2023 were included in this review. Samples of HIV-DLBCL were relatively small (16-110). Cohort effects influenced frequencies of molecular characteristics hence their impact on survival was not clear. Molecular features were distinct from HIVunrelated DLBCL. The most frequently assessed characteristic was cell of origin (81.3% of studies). Somatic mutations were the least researched (6.3% of studies). Overall, biomarker identification in HIV-DLBCL requires broader richer data from larger or pooled samples using more powerful techniques such as next-generation sequencing. [ABSTRACT FROM AUTHOR]

Background: Diffuse large B cell lymphoma (DLBCL) is the most prevalent subtype of non-Hodgkin's lymphoma, characterized by remarkable molecular heterogeneity. This study evaluates the prevalence of MYC, BCL2, and BCL6 gene rearrangements among Iranian DLBCL patients. Method: This historical cohort study encompassed 152 patients drawn from six reference hospitals who participated in the research. Interphase dual-color break-apart fluorescence in situ hybridization (FISH) was applied to formalin-fixed paraffin-embedded DLBCL specimens categorized as "not otherwise specified" alongside 20 normal controls. Survival data was analyzed using the Kaplan-Meier method and the Log-Rank test. Results: Among the patients, 7 (4.8%), 4 (2.9%), and 15 (10.2%) exhibited MYC, BCL2, and BCL6 rearrangements, respectively. Additionally, 1.5% of the patients demonstrated double-hit (DH) characteristics with both MYC and BCL2 rearrangements, while no triple rearrangements were observed. The presence of rearrangements appeared to be independent of clinicopathological variables. Patients with rearrangements experienced reduced survival durations, with reductions of 26.6, 31.2, 9.1, and 34.2 months for MYC, BCL2, BCL6-rearranged, and DH tumors, respectively (P > 0.05). Adverse prognosis was associated with age, activated B-cell-like phenotype, disease stage, B symptoms, lactate dehydrogenase levels, and risk grouping according to the National Comprehensive Cancer Network (NCCN) International Prognostic Index. Conclusion: DLBCL cases featuring MYC, BCL2, and/or BCL6 translocations are relatively rare. Patients harboring these rearrangements tend to exhibit aggressive disease progression with shortened overall survival. However, these differences did not reach statistical significance, necessitating further research to validate the incorporation of such tests into the routine workup of DLBCL patients. [ABSTRACT FROM AUTHOR]

Aims: Osteoporosis is characterized by decreased trabecular bone volume, and microarchitectural deterioration in the medullary cavity. Interleukin-19 (IL-19), a member of the IL-10 family, is an anti-inflammatory cytokine produced primarily by macrophages. The aim of our study was to investigate the effect of IL-19 on osteoporosis. Methods: Blood and femoral bone marrow suspension IL-19 levels were first measured in the lipopolysaccharide (LPS)-induced bone loss model. Small interfering RNA (siRNA) was applied to knock down IL-19 for further validation. Thereafter, osteoclast production was stimulated with IL-19 in combination with mouse macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor-κB ligand (RANKL). The effect of IL-19 was subsequently evaluated using tartrate-resistant acid phosphatase (TRAP) staining and quantitative real-time polymerase chain reaction (RT-qPCR). The effect of IL-19 on osteoprotegerin (OPG) was then assessed using in vitro recombinant IL-19 treatment of primary osteoblasts and MLO-Y4 osteoblast cell line. Finally, transient transfection experiments and chromatin immunoprecipitation (ChIP) experiments were used to examine the exact mechanism of action. Results: In the LPS-induced bone loss mouse model, the levels of IL-19 in peripheral blood serum and femoral bone marrow suspension were significantly increased. The in vivo results indicated that global IL-19 deletion had no significant effect on RANKL content in the serum and bone marrow, but could increase the content of OPG in serum and femoral bone marrow, suggesting that IL-19 inhibits OPG expression in bone marrow mesenchymal stem cells (BMSCs) and thus increases bone resorption. Conclusion: IL-19 promotes bone resorption by suppressing OPG expression in BMSCs in a LPS-induced bone loss mouse model, which highlights the potential benefits and side effects of IL-19 for future clinical applications. Cite this article: Bone Joint Res 2023;12(11):691–701.

An inability to make the diagnosis of endometriosis or evaluate lesion response to treatment without surgery is a clear impediment to understanding the disease and to developing new therapies. The need is particularly strong for rASRM Stage 1 or 2 disease, since higher stage (rASRM Stage 3 or 4) endometriosis can often be diagnosed by ultrasound or other imaging techniques. Despite promising findings in association studies, no biomarkers or nonsurgical diagnostic or evaluation methods for Stage 1 or Stage 2 endometriosis has yet been clinically validated. Admittedly, validation is difficult, since surgery is required as a gold standard diagnostic method for comparison. This manuscript is aimed as a succinct review of what is known about nonsurgical approaches to detect and assess endometriosis, with an emphasis on Stage 1 and 2. [ABSTRACT FROM AUTHOR]

Amyloid‐β1‐42 (Aβ1‐42) is strongly associated with Alzheimer's disease (AD). The aim of this study is to elucidate whether and how miR‐6076 participates in the modulation of amyloid‐β (Aβ)‐induced neuronal damage. To construct the neuronal damage model, SH‐SY5Y cells were treated with Aβ1‐42. By qRT‐PCR, we found that miR‐6076 is significantly upregulated in Aβ1‐42‐treated SH‐SY5Y cells. After miR‐6076 inhibition, p‐Tau and apoptosis levels were downregulated, and cell viability was increased. Through online bioinformatics analysis, we found that B‐cell lymphoma 6 (BCL6) was a directly target of miR‐6076 via dual‐luciferase reporter assay. BCL6 overexpression mediated the decrease in elevated p‐Tau levels and increased viability in SH‐SY5Y cells following Aβ1‐42 treatment. Our results suggest that down‐regulation of miR‐6076 could attenuate Aβ1‐42‐induced neuronal damage by targeting BCL6, which provided a possible target to pursue for prevention and treatment of Aβ‐induced neuronal damage in AD. [ABSTRACT FROM AUTHOR]

Introduction. Cutaneous melanoma is one of the most aggressive malignant tumors, and its nodular form with vertical growth is characterized by unfavorable prognosis. However, in the recent years due to advances in basic oncology, a breakthrough in drug therapy of this pathology was made. To a great extent, it is linked to implementation of new therapy with checkpoint inhibitors. The best and longest response rates of cutaneous melanoma to this treatment were achieved compared to other oncological diseases. This fact can be explained by immunogenicity of cutaneous melanoma, high mutational load, as well as features of its tumor microenvironment, where in most cases high infiltration by immunocompetent cell is observed. However, immune cells vary by their composition and functions. Some of them can even promote tumor growth. Therefore, study of cell composition, degree and distribution of immune infiltration in the tumor can help identify potential factors of favorable and unfavorable prognosis for cutaneous melanoma which is important in clinical practice.Aim. To determine the frequency of CD3+-, CD4+-, CD8+-T-lymphocytes, CD163, BCL6 and SOX10 expression in patients with primary nodular cutaneous melanoma, as well as correlation of these markers with each other and standard morphological parameters for this non-epithelial malignant tumor.Materials and methods. In the study, the expression frequency of CD3+-, CD4+-, CD8+-T-lymphocytes, CD163, BCL6 and SOX10 in the postoperative material of 20 patients with true primary nodular cutaneous melanoma was measured using immunohistological analysis. The correlation of these markers with each other and standard morphological parameters was determined.Results. In most cases of nodular cutaneous melanoma, moderate and marked lymphocytic (immune) infiltration (grade II–III) was observed with no correlation with Breslow tumor thickness. Study of the ratio between CD4-positive T helpers and CD8-positive cytotoxic T lymphocytes in the tumor microenvironment showed that the number of the latter increased the higher was the degree of immune infiltrate. Markedness of macrophage infiltration directly correlated with markedness of lymphocytic infiltration. BCL6 expression in lymphocytes was observed in all cases of infiltration.Conclusion. Immune infiltrate in nodular cutaneous melanoma is a multicomponent, dynamic microenvironment containing both antitumor and tumor-promoting components with balance shifting to one or other side. Their qualitative, quantitative and, possibly, topographic ratios in the primary lesion of cutaneous melanoma affect the effectiveness of drugs and disease prognosis. Knowledge on the predominance of components negatively affecting tumor growth in the primary lesion can help an oncologist in selection of correct treatment tactics and disease observation.

Transcriptional repressor B cell lymphoma 6 (Bcl6) is a major transcription factor involved in Tfh cell differentiation and germinal center response, which is regulated by a variety of biological processes. However, the functional impact of post-translational modifications, particularly lysine β-hydroxybutyrylation (Kbhb), on Bcl6 remains elusive. In this study, we revealed that Bcl6 is modified by Kbhb to affect Tfh cell differentiation, resulting in the decrease of cell population and cytokine IL-21. Furthermore, the modification sites are identified from enzymatic reactions to be lysine residues at positions 376, 377, and 379 by mass spectrometry, which is confirmed by site-directed mutagenesis and functional analyses. Collectively, our present study provides evidence on the Kbhb modification of Bcl6 and also generates new insights into the regulation of Tfh cell differentiation, which is a starting point for a thorough understanding of the functional involvement of Kbhb modification in the differentiations of Tfh and other T cells. [ABSTRACT FROM AUTHOR]

Background: The clinical and genetic heterogeneity of diffuse large B-cell lymphoma (DLBCL) presents distinct challenges in predicting response to therapy and overall prognosis. The main objective of this study was to assess the application of the immunohistochemistry- and interphase fluorescence in situ hybridization (FISH)-based molecular markers in the diagnosis of DLBCL and its prognostic value in patients treated with rituximab-based immunochemotherapy. Methods: This is a multicenter, retrospective study, which analyzed data from 7 Hungarian hematology centers. Eligible patients were adults, had a histologically confirmed diagnosis of DLBCL, were treated with rituximab-based immunochemotherapy in the first line, and had available clinicopathological data including International Prognostic Index (IPI). On the specimens, immunohistochemistry and FISH methods were performed. Germinal center B-cell like (GCB) and non-GCB subtypes were classified by the Hans algorithm. Outcomes included overall survival (OS), event-free survival (EFS), and EFS at 2 years (EFS24). For survival analysis, we used Kaplan-Meier curves with the logrank test and multivariate Cox regression. Results: A total of 247 DLBCL cases were included. Cases were positive for MYC, BCL2, BCL6, and MUM1 expression in 52.1%, 66.2%, 72.6%, and 77.8%, respectively. BCL6 translocation, BCL2 gene copy number (GCN) gain, IGH:: MYC translocation, MYC GCN gain, IGH::BCL2 translocation, and BCL6 GCN gain were detected in 21.4%, 14.1%, 7.3%, 1.8%, 7.3%, and 0.9%, respectively. At a median follow-up of 52 months, 140 patients (56.7%) had disease progression or relapse. The Kaplan-Meier estimate for EFS24 was 56.2% (CI: 50.4-62.8%). In univariate analysis, only IPI and BCL6 expression were significant predictors of both OS and EFS, whereas MUM1 predicted EFS only. In multivariate analysis, the IPI score was a significant independent negative, whereas MIB-1 and BCL6 protein expressions were significant independent positive predictors of both OS and EFS. Conclusion: In our study, we found that only IPI, BCL6 protein expression and MIB-1 protein expression are independent predictors of survival outcomes in DLBCL. We did not find any difference in survival by GCB vs. non-GCB subtypes. These findings may improve prognostication in DLBCL and can contribute to designing further research in the area. [ABSTRACT FROM AUTHOR]

Control of diverse pathogens requires an adaptive antibody response, dependent on cellular division of labor to allocate antigen-dependent B- and CD4+ T-cell fates that collaborate to control the quantity and quality of antibody. This is orchestrated by the dynamic action of key transcriptional regulators mediating gene expression programs in response to pathogen-specific environmental inputs. We describe a conserved, likely ancient, gene regulatory network that intriguingly operates contemporaneously in B and CD4+ T cells to control their cell fate dynamics and thus, the character of the antibody response. The remarkable output of this network derives from graded expression, designated by antigen receptor signal strength, of a pivotal transcription factor that regulates alternate cell fate choices.

Abstract Background B-cell lymphoma 6 (BCL6) is a transcription repressor that plays a tumor suppressor or promoting role in various tumors. However, its function and molecular mechanism in gastric cancer (GC) remain unclear. Ferroptosis, a novel programmed cell death, is closely related to tumor development. In this research, we aimed to explore the role and mechanism of BCL6 in malignant progression and ferroptosis of gastric cancer. Methods Firstly, BCL6 was identified as an important biomarker that attenuated the proliferation and metastasis of GC through tumor microarrays and confirmed in GC cell lines. RNA sequence was performed to explore the downstream genes of BCL6. The underlying mechanisms were further investigated by ChIP, dual luciferase reporter assays and rescue experiments. Cell death, lipid peroxidation, MDA and Fe2+ level were detected to determine the effect of BCL6 on ferroptosis and the mechanism was revealed. CHX, MG132 treatment and rescue experiments were used to explore the upstream regulatory mechanism of BCL6. Results Here we showed that BCL6 expression was significantly decreased in GC tissues, and patients with low BCL6 expression showed more malignant clinical features and poor prognosis. The upregulation of BCL6 may significantly inhibited the proliferation and metastasis of GC cells in vitro and in vivo. In addition, we found that BCL6 directly binds and transcriptionally represses Wnt receptor Frizzled 7 (FZD7) to inhibit the proliferation, metastasis of GC cells. We also found that BCL6 promoted lipid peroxidation, MDA and Fe2+ level to facilitate ferroptosis of GC cells by FZD7/β-catenin/TP63/GPX4 pathway. Furthermore, the expression and function of BCL6 in GC were regulated by the ring finger protein 180 (RNF180)/ras homolog gene family member C (RhoC) pathway, which had been elucidated to be involved in significantly mediating the proliferation and metastasis of GC cells. Conclusions In summary, BCL6 should be considered a potential intermediate tumor suppressor to inhibit the malignant progression and induce ferroptosis, which might be a promising molecular biomarker for further mechanistic investigation of GC.

Ly6Clo monocytes are a myeloid subset that specializes in the surveillance of vascular endothelium. Ly6Clo monocytes have been shown to derive from Ly6Chi monocytes. NOTCH2 signaling has been implicated as a trigger for Ly6Clo monocyte development, but the basis for this effect is unclear. Here, we examined the impact of NOTCH2 signaling of myeloid progenitors on the development of Ly6Clo monocytes in vitro. NOTCH2 signaling induced by delta- like ligand 1 (DLL1) efficiently induced the transition of Ly6Chi TREML4- monocytes into Ly6Clo TREML4+ monocytes. We further identified two additional transcriptional requirements for development of Ly6Clo monocytes. Deletion of BCL6 from myeloid progenitors abrogated development of Ly6Clo monocytes. IRF2 was also required for Ly6Clo monocyte development in a cell-intrinsic manner. DLL1-induced in vitro transition into Ly6Clo TREML4+ monocytes required IRF2 but unexpectedly could occur in the absence of NUR77 or BCL6. These results imply a transcriptional hierarchy for these factors in controlling Ly6Clo monocyte development. [ABSTRACT FROM AUTHOR]

Introduction: Despite long-term integrated control programs for Eimeria stiedai infection in China, hepatic coccidiosis in rabbits persists. Th1, Th2, Th17, Treg, Th9, and Th21 cells are involved in immune responses during pathogen infection. It is unclear whether Th cell subsets are also involved in E. stiedai infection. Their roles in the immunopathology of this infection remain unknown. Therefore, monitoring these T-cell subsets' immune responses during primary infection of E. stiedai at both transcriptional (mRNA) and protein (cytokines) levels is essential. Methods: In experimentally infected New Zealand white rabbits, mRNA expression levels of their transcript-TBX2 (Th1), GATA3 (Th2), RORC (Th17), Foxp3 (Treg), SPI1 (Th9), and BCL6 (Th21)--were evaluated using quantitative real-time polymerase chain reaction (qRT-PCR), whereas Th1 (IFN-g and TNF-a), Th2 (IL4), Th17 (IL17A and IL6), Treg (IL10 and TGF-b1), Th9 (IL9), and Th21 (IL21) cytokines were measured using enzyme-linked immunosorbent assays (ELISAs). Results: We found that levels of TBX2, GATA3, RORC, SPI1, and BCL6 in the livers of infected rabbits were elevated on days 5 and 15 post-infection (PI). The concentrations of their distinctive cytokines IFN-g and TNF-a forTh1, IL4 forTh2, IL17A for Th17, IL9 for Th9, IL21 for Th21, and IL10 for Treg IL10 were also significantly increased on days 5 and 15 PI, respectively (p < 0.05). On day 23 PI, GATA3 with its cytokine IL4, RORC with IL17A, Foxp3 with IL10 and TGF-b1, and SPI1 with IL9 were significantly decreased, butTBX2 with IFN-g and IL6 remained elevated. Discussion: Our findings are the first evidence of Th1/Th2/Treg/Th17/Th9/Th21 changes in E. stiedai-infected rabbits and provide insights into immune regulation mechanisms and possible vaccine development. [ABSTRACT FROM AUTHOR]

To determine whether B-cell lymphoma 6 (BCL6), an endometriosis-associated marker postulated to predict poor pregnancy outcomes, is differentially expressed in the window of implantation with various uterine preparation regimens commonly used for frozen embryo transfers. A retrospective cohort study. An academic center. Patients with infertility who underwent endometrial biopsy for BCL6 evaluation Exogenous estradiol and/or progesterone. Endometrial BCL6 histological score (HSCORE) and overexpression (HSCORE >1.4) Two hundred and forty-four patients were included in the analysis: 76 patients were sampled in a natural menstrual cycle without exogenous hormone exposure (NC), 25 under a modified natural cycle embryo transfer protocol with choriogonadotropin alfa injection followed by luteal phase vaginal progesterone supplementation (mNC), and 143 under a programmed cycle embryo transfer protocol, with estradiol administration followed by addition of intramuscular progesterone-in-oil injections (PC). Median HSCORE (interquartile range) was the highest in NC (3.0 [1.8–3.6]). BCL6 expression was significantly lower in mNC (1.1 [0.4–2.1]) and PC groups (0.8 [0.3–1.3]) compared with NC. In addition, BCL6 overexpression (HSCORE >1.4) was observed in 80.3% of NC, 40.0 % of mNC, and 23.1 % of PC. After adjusting for covariates, the endometrium exposed to exogenous progesterone had significantly lower odds of BCL6 overexpression than that of a natural menstrual cycle (adjusted odds ratio, 0.12 [95% CI 0.04–0.35] for mNC; and odds ratio, 0.08 [95% CI 0.04-0.17] for PC). BCL6 expression differs by the type of uterine preparation method, with lower levels observed with exogenous progesterone exposure. The validity and utility of BCL6 testing under medicated endometrial state warrants further investigation. [ABSTRACT FROM AUTHOR]

BackgroundThe clinical and genetic heterogeneity of diffuse large B-cell lymphoma (DLBCL) presents distinct challenges in predicting response to therapy and overall prognosis. The main objective of this study was to assess the application of the immunohistochemistry- and interphase fluorescence in situ hybridization (FISH)-based molecular markers in the diagnosis of DLBCL and its prognostic value in patients treated with rituximab-based immunochemotherapy.MethodsThis is a multicenter, retrospective study, which analyzed data from 7 Hungarian hematology centers. Eligible patients were adults, had a histologically confirmed diagnosis of DLBCL, were treated with rituximab-based immunochemotherapy in the first line, and had available clinicopathological data including International Prognostic Index (IPI). On the specimens, immunohistochemistry and FISH methods were performed. Germinal center B-cell like (GCB) and non-GCB subtypes were classified by the Hans algorithm. Outcomes included overall survival (OS), event-free survival (EFS), and EFS at 2 years (EFS24). For survival analysis, we used Kaplan-Meier curves with the log-rank test and multivariate Cox regression.ResultsA total of 247 DLBCL cases were included. Cases were positive for MYC, BCL2, BCL6, and MUM1 expression in 52.1%, 66.2%, 72.6%, and 77.8%, respectively. BCL6 translocation, BCL2 gene copy number (GCN) gain, IGH::MYC translocation, MYC GCN gain, IGH::BCL2 translocation, and BCL6 GCN gain were detected in 21.4%, 14.1%, 7.3%, 1.8%, 7.3%, and 0.9%, respectively. At a median follow-up of 52 months, 140 patients (56.7%) had disease progression or relapse. The Kaplan-Meier estimate for EFS24 was 56.2% (CI: 50.4–62.8%). In univariate analysis, only IPI and BCL6 expression were significant predictors of both OS and EFS, whereas MUM1 predicted EFS only. In multivariate analysis, the IPI score was a significant independent negative, whereas MIB-1 and BCL6 protein expressions were significant independent positive predictors of both OS and EFS.ConclusionIn our study, we found that only IPI, BCL6 protein expression and MIB-1 protein expression are independent predictors of survival outcomes in DLBCL. We did not find any difference in survival by GCB vs. non-GCB subtypes. These findings may improve prognostication in DLBCL and can contribute to designing further research in the area.

Chromosomal rearrangements of the mixed lineage leukemia (MLL) gene occur in ∼10% of B-cell acute lymphoblastic leukemia (B-ALL) and define a group of patients with dismal outcomes. Immunohistochemical staining of bone marrow biopsies from most of these patients revealed aberrant expression of BCL6, a transcription factor that promotes oncogenic B-cell transformation and drug resistance in B-ALL. Our genetic and ChIP-seq (chromatin immunoprecipitation [ChIP] combined with high-throughput sequencing) analyses showed that MLL-AF4 and MLL-ENL fusions directly bound to the BCL6 promoter and up-regulated BCL6 expression. While oncogenic MLL fusions strongly induced aberrant BCL6 expression in B-ALL cells, germline MLL was required to up-regulate Bcl6 in response to physiological stimuli during normal B-cell development. Inducible expression of Bcl6 increased MLL mRNA levels, which was reversed by genetic deletion and pharmacological inhibition of Bcl6, suggesting a positive feedback loop between MLL and BCL6. Highlighting the central role of BCL6 in MLL-rearranged B-ALL, conditional deletion and pharmacological inhibition of BCL6 compromised leukemogenesis in transplant recipient mice and restored sensitivity to vincristine chemotherapy in MLL-rearranged B-ALL patient samples. Oncogenic MLL fusions strongly induced transcriptional activation of the proapoptotic BH3-only molecule BIM, while BCL6 was required to curb MLL-induced expression of BIM. Notably, peptide (RI-BPI) and small molecule (FX1) BCL6 inhibitors derepressed BIM and synergized with the BH3-mimetic ABT-199 in eradicating MLL-rearranged B-ALL cells. These findings uncover MLL-dependent transcriptional activation of BCL6 as a previously unrecognized requirement of malignant transformation by oncogenic MLL fusions and identified BCL6 as a novel target for the treatment of MLL-rearranged B-ALL.

Abstract Background Esophageal adenocarcinoma is a lethal disease. For locally advanced patients, neoadjuvant chemoradiotherapy followed by surgery is the standard of care. Risk stratification relies heavily on clinicopathologic features, particularly pathologic response, which is inadequate, therefore establishing the need for new and reliable biomarkers for risk stratification. Methods Thirty four patients with locally advanced esophageal adenocarcinoma were analyzed, of which 21 received a CROSS regimen with carboplatin, paclitaxel, and radiation. Capture-based targeted sequencing was performed on the paired baseline and post-treatment samples. Differentially mutated gene analysis between responders and non-responders of treatment was performed to determine predictors of response. A univariate Cox proportional hazard regression was used to examine associations between gene mutation status and overall survival. Results A 3-gene signature, based on mutations in EPHA5, BCL6, and ERBB2, was identified that robustly predicts response to the CROSS regimen. For this model, sensitivity was 84.6% and specificity was 100%. Independently, a 9 gene signature was created using APC, MAP3K6, ETS1, CSF3R, PDGFRB, GATA2, ARID1A, PML, and FGF6, which significantly stratifies patients into risk categories, prognosticating for improved relapse-free (p = 4.73E-03) and overall survival (p = 3.325E-06). The sensitivity for this model was 73.33% and the specificity was 94.74%. Conclusion We have identified a 3-gene signature (EPHA5, BCL6, and ERBB2) that is predictive of response to neoadjuvant chemoradiotherapy and a separate prognostic 9-gene classifier that predicts survival outcomes. These panels provide significant potential for personalized management of locally advanced esophageal cancer.

Using a whole-genome assembly of Bos taurus, I applied my bioinformatics strategy to locate candidate imprinting control regions (ICRs) genome-wide. In mammals, genomic imprinting plays essential roles in embryogenesis. In my strategy, peaks in plots mark the locations of known, inferred, and candidate ICRs. Genes in the vicinity of candidate ICRs correspond to potential imprinted genes. By displaying my datasets on the UCSC genome browser, one could view peak positions with respect to genomic landmarks. I give two examples of candidate ICRs in loci that influence spermatogenesis in bulls: CNNM1 and CNR1. I also give examples of candidate ICRs in loci that influence muscle development: SIX1 and BCL6. By examining the ENCODE data reported for mice, I deduced regulatory clues about cattle. I focused on DNase I hypersensitive sites (DHSs). Such sites reveal accessibility of chromatin to regulators of gene expression. For inspection, I chose DHSs in chromatin from mouse embryonic stem cells (ESCs) ES-E14, mesoderm, brain, heart, and skeletal muscle. The ENCODE data revealed that the SIX1 promoter was accessible to the transcription initiation apparatus in mouse ESCs, mesoderm, and skeletal muscles. The data also revealed accessibility of BCL6 locus to regulatory proteins in mouse ESCs and examined tissues. [ABSTRACT FROM AUTHOR]

Background: B-cell lymphoma 6 (BCL6) is a transcription repressor that plays a tumor suppressor or promoting role in various tumors. However, its function and molecular mechanism in gastric cancer (GC) remain unclear. Ferroptosis, a novel programmed cell death, is closely related to tumor development. In this research, we aimed to explore the role and mechanism of BCL6 in malignant progression and ferroptosis of gastric cancer. Methods: Firstly, BCL6 was identified as an important biomarker that attenuated the proliferation and metastasis of GC through tumor microarrays and confirmed in GC cell lines. RNA sequence was performed to explore the downstream genes of BCL6. The underlying mechanisms were further investigated by ChIP, dual luciferase reporter assays and rescue experiments. Cell death, lipid peroxidation, MDA and Fe2+ level were detected to determine the effect of BCL6 on ferroptosis and the mechanism was revealed. CHX, MG132 treatment and rescue experiments were used to explore the upstream regulatory mechanism of BCL6. Results: Here we showed that BCL6 expression was significantly decreased in GC tissues, and patients with low BCL6 expression showed more malignant clinical features and poor prognosis. The upregulation of BCL6 may significantly inhibited the proliferation and metastasis of GC cells in vitro and in vivo. In addition, we found that BCL6 directly binds and transcriptionally represses Wnt receptor Frizzled 7 (FZD7) to inhibit the proliferation, metastasis of GC cells. We also found that BCL6 promoted lipid peroxidation, MDA and Fe2+ level to facilitate ferroptosis of GC cells by FZD7/β-catenin/TP63/GPX4 pathway. Furthermore, the expression and function of BCL6 in GC were regulated by the ring finger protein 180 (RNF180)/ras homolog gene family member C (RhoC) pathway, which had been elucidated to be involved in significantly mediating the proliferation and metastasis of GC cells. Conclusions: In summary, BCL6 should be considered a potential intermediate tumor suppressor to inhibit the malignant progression and induce ferroptosis, which might be a promising molecular biomarker for further mechanistic investigation of GC. [ABSTRACT FROM AUTHOR]

We report a rare case of ALK-positive large B cell lymphoma which initially presented as a circumscribed breast mass in a young woman mimicking fibroadenoma. The lymphoma demonstrated typical immunoblastic morphology with monomorphic round nuclei and prominent central nucleoli. Immunophenotypically, the lymphoma was positive for MUM1,CD138, BOB1, OCT2, PAX5 (focal), CD4, and was negative for CD20, CD79a and all other T cell antigens. Immunostaining for the ALK protein revealed the characteristic granular cytoplasmic staining typical for ALK-positive large B cell lymphoma with an ALK::CTCL fusion confirmed on genomic profiling study. Notably the cells also expressed CD10 and BCL6. Staging revealed disseminated disease with blood, bone marrow and liver involvement. To our knowledge, this is the first report of ALK-positive large B cell lymphoma initially presenting as a breast lesion. Additionally, expression of CD10 and BCL6 suggested a germinal center origin for the lesion. [ABSTRACT FROM AUTHOR]

Epidemiological evidence supports an association between cow's milk consumption and the risk of diffuse large B-cell lymphoma (DLBCL), the most common non-Hodgkin lymphoma worldwide. This narrative review intends to elucidate the potential impact of milk-related agents, predominantly milk-derived exosomes (MDEs) and their microRNAs (miRs) in lymphomagenesis. Upregulation of PI3K-AKT-mTORC1 signaling is a common feature of DLBCL. Increased expression of B cell lymphoma 6 (BCL6) and suppression of B lymphocyte-induced maturation protein 1 (BLIMP1)/PR domain-containing protein 1 (PRDM1) are crucial pathological deviations in DLBCL. Translational evidence indicates that during the breastfeeding period, human MDE miRs support B cell proliferation via epigenetic upregulation of BCL6 (via miR-148a-3p-mediated suppression of DNA methyltransferase 1 (DNMT1) and miR-155-5p/miR-29b-5p-mediated suppression of activation-induced cytidine deaminase (AICDA) and suppression of BLIMP1 (via MDE let-7-5p/miR-125b-5p-targeting of PRDM1). After weaning with the physiological termination of MDE miR signaling, the infant's BCL6 expression and B cell proliferation declines, whereas BLIMP1-mediated B cell maturation for adequate own antibody production rises. Because human and bovine MDE miRs share identical nucleotide sequences, the consumption of pasteurized cow's milk in adults with the continued transfer of bioactive bovine MDE miRs may de-differentiate B cells back to the neonatal "proliferation-dominated" B cell phenotype maintaining an increased BLC6/BLIMP1 ratio. Persistent milk-induced epigenetic dysregulation of BCL6 and BLIMP1 expression may thus represent a novel driving mechanism in B cell lymphomagenesis. Bovine MDEs and their miR cargo have to be considered potential pathogens that should be removed from the human food chain. [ABSTRACT FROM AUTHOR]

Background: B cell lymphoma 6 (BCL6) is an important transcription factor of T follicular helper (Tfh) cells, which regulate the humoral response by supporting the maturation of germinal center B cells and plasma cells. The aim of this study is to investigate the expansion of T follicular helper cells and the effect of the BCL6 inhibitor FX1 in acute and chronic cardiac transplant rejection models. Methods: A mouse model of acute and chronic cardiac transplant rejection was established. Splenocytes were collected at different time points after transplantation for CXCR5+PD-1+ and CXCR5+BCL6+ Tfh cells detection by flow cytometry (FCM). Next, we treated the cardiac transplant with BCL6 inhibitor FX1 and the survival of grafts was recorded. The hematoxylin and eosin, Elastica van Gieson, and Masson staining of cardiac grafts was performed for the pathological analysis. Furthermore, the proportion and number of CD4+ T cells, effector CD4+ T cells (CD44+CD62L-), proliferating CD4+ T cells (Ki67+), and Tfh cells in the spleen were detected by FCM. The cells related to humoral response (plasma cells, germinal center B cells, IgG1+ B cells) and donor-specific antibody were also detected. Results: We found that the Tfh cells were significantly increased in the recipient mice on day 14 post transplantation. During the acute cardiac transplant rejection, even the BCL6 inhibitor FX1 did not prolong the survival or attenuate the immune response of cardiac graft, the expansion of Tfh cell expansion inhibit. During the chronic cardiac transplant rejection, FX1 prolonged survival of cardiac graft, and prevented occlusion and fibrosis of vascular in cardiac grafts. FX1 also decreased the proportion and number of splenic CD4+ T cells, effector CD4+ T cells, proliferating CD4+ T cells, and Tfh cells in mice with chronic rejection. Moreover, FX1 also inhibited the proportion and number of splenic plasma cells, germinal center B cells, IgG1+ B cells, and the donor-specific antibody in recipient mice. Conclusion: We found BCL6 inhibitor FX1 protects chronic cardiac transplant rejection and inhibits the expansion of Tfh cells and the humoral response, which suggest that BCL6 is a potential therapeutic target of the treatment for chronic cardiac transplant rejection. [ABSTRACT FROM AUTHOR]

Abstract Background Ionizing radiation (IR) can induce pulmonary fibrosis by causing epithelial mesenchymal transition (EMT), but the exact mechanism has not been elucidated. To investigate the molecular mechanism of how radiation induces pulmonary fibrosis by altering miR-486-3p content and thus inducing EMT. Methods The changes of miR-486-3p in cells after irradiation were detected by RT-qPCR. Western blot was used to detect the changes of cellular epithelial marker protein E-cadherin, mesenchymal marker N-cadherin, Vimentin and other proteins. The target gene of miR-486-3p was predicted by bioinformatics method and the binding site was verified by dual luciferase reporter system. In vivo experiments, adeno-associated virus (AAV) was used to carry miR-486-3p mimic to lung. Radiation-induced pulmonary fibrosis (RIPF) model was constructed by 25Gy60Co γ-rays. The structural changes of mouse lung were observed by HE and Masson staining. The expression of relevant proteins in mice was detected by immunohistochemistry. Results IR could decrease the miR-486-3p levels in vitro and in vivo, and that effect was closely correlated to the occurrence of RIPF. The expression of Snail, which induces EMT, was shown to be restrained by miR-486-3p. Therefore, knockdown of Snail blocked the EMT process induced by radiation or knockdown of miR-486-3p. In addition, the molecular mechanism underlying the IR-induced miRNA level reduction was explored. The increased in BCL6 could inhibit the formation of pri-miR-486-3p, thereby reducing the levels of miR-486-3p in the alveolar epithelial cells, which would otherwise promote EMT and contribute to RIPF by targeting Snail. Conclusion IR can exacerbate RIPF in mice by activating the transcription factor BCL6, which inhibits the transcription of miR-486-3p and decreases its content, which in turn increases the content of the target gene slug and triggers EMT.

Cancer development is a long-lasting process during which macrophages play a pivotal role. However, how macrophages maintain their cellular identity, persistence, expanding and pro-tumor property during malignant progression remains elusive. Inspired by the recent report of the activation of stem cell-like self-renewal mechanism in mature macrophages, we postulate that intra-tumoral macrophages might be trained to assume stem-like properties and memory-like activity favoring cancer development. Herein we demonstrated that tumor infiltrating macrophages rapidly converted into the CD11b+F4/80+Ly6C−Bcl6+ phenotype, and adopted stem cell-like properties involving expression of stemness-related genes, long-term persistence and self-renewing. Importantly, Bcl6+ macrophages stably maintained cell identity, gene signature, metabolic profile, and pro-tumor property even after long-term culture in tumor-free medium, which were hence termed stem cell-like memory macrophages (SMMs). Mechanistically, we showed that transcriptional factor Bcl6 co-opted the demethylase Tet2 and the deacetylase SIRT1 to confer the epigenetic imprinting and mitochondrial metabolic traits to SMMs, bolstering the stability and longevity of trained immunity in tumor-associated macrophages (TAMs). Furthermore, tumor-derived redHMGB1 was identified as the priming signal, which, through TLR4 and mTOR/AKT pathway, induced Bcl6-driven program underpinning SMMs generation. Collectively, our study uncovers a distinct macrophage population with a hybrid of stem cell and memory cell properties, and unveils a regulatory mechanism that integrates transcriptional, epigenetic and metabolic pathways to promote long-lasting pro-tumor immunity. [ABSTRACT FROM AUTHOR]

Background: Congenital heart disease (CHD) frequently manifests as a complex phenotype and approximately one‐third of cases may be caused by genetic factors. BCOR, an X‐linked gene encoding the corepressor of BCL6, has been demonstrated to be closely involved in human heart development. However, whether BCOR variants represent the genetic etiology underlying CHD needs further investigation. Methods: We performed whole exome sequencing on CHD nuclear families and identified a candidate gene, BCOR, by robust bioinformatic analysis and medical literature searches. Targeted DNA sequencing of the candidate gene was conducted and then the association between variants and the risk of developing CHD was analyzed. The effects of BCOR mutations on gene expression, localization, protein interaction, and signaling pathways were evaluated in vitro. Results: We identified a BCOR hemizygous missense variant (c.1448C>T, p.Pro483Leu) in a male proband presented with CHD/heterotaxy. Sanger sequencing confirmed that this variant was inherited from his asymptomatic mother. Interestingly, through literature searches, we observed another novel BCOR hemizygous missense variant (c.1619G>A, p.Arg540Gln) in a CHD patient with heterotaxy, supporting the pathogenic evidence of BCOR variants. Functional experiments conducted in vitro revealed that the variant p.Pro483Leu altered the subcellular localization of BCOR protein, disrupted its interaction with BCL6, and significantly promoted cell proliferation, whereas the variant p.Arg540Gln displayed no obvious effects. Nevertheless, transcriptional analysis revealed that down‐regulation of BCOR substantially enhanced the activities of mitogen‐activated protein and phosphoinositide 3‐kinase‐AKT signaling pathways, which are closely attributed to heart development. Targeted sequencing of 932 sporadic CHD patients enriched nine variants of BCOR predicted as likely rare and damaging and a septal defect was present in 81.8% (9/11) of them, including the two probands, which was consistent with the possible phenotype caused by BCOR defects. Conclusions: The findings of the present study indicate that variants in BCOR may predispose individuals to CHD in the Chinese Han population. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is the most common joint disease and its pathogenic mechanism remains to be ensured. This study focused on the regulatory relation between B-cell lymphoma 6 (BCL6) and G-protein-coupled receptor 61 (GPR61) underlying IL-1β in OA. Real-time quantitative polymerase chain reaction and western blot were performed for mRNA and protein detection. Oxidative injury was assessed by reactive oxygen species (ROS), malondialdehyde (MDA), and glutathione (GSH) via kits. Fe 2+ level was measured via an iron assay kit. Relation analysis between BCL6 and GPR61 was implemented employing ChIP assay and dual-luciferase reporter assay. GPR61 was downregulated in OA samples and IL-1β-induced C28/I2 cells. IL-1β-induced cell inflammation, extracellular matrix (ECM) degradation, oxidative stress, and ferroptosis were all returned by overexpression of GPR61. BCL6 downregulation was detected in OA patients and IL-1β-exposed C28/I2 cells. BCL6 could promote the transcription of GPR61. BCL6 suppressed IL-1β-induced OA progression by upregulating GPR61. The BCL6/GPR61 axis activated the PKA/CREB pathway in IL-1β-treated C28/I2 cells. The above results suggested that BCL6 mitigated OA progression induced by IL-1β by enhancing transcription of GPR61. BCL6/GPR61/PKA/CREB axis may be considered as a novel regulatory mechanism in OA, and BCL6 has the potential to act as a novel target for OA., (© 2024 The Societies and John Wiley & Sons Australia, Ltd.)

Objectives: High-grade B-cell lymphoma (HGBL), introduced in the 2016 World Health Organization (WHO) revised fourth edition classification, included cases defined by MYC and BCL2 and/or BCL6 rearrangements or by high-grade morphology. Diagnostic criteria and nomenclature for these lymphomas were refined in the 2022 WHO fifth edition (WHO-5) classification and International Consensus Classification (ICC). This review describes our approach to the diagnosis of HGBL., Methods: Two cases are presented illustrating how we diagnose HGBL, including 1 case harboring MYC and BCL6 rearrangements and a second showing TdT expression in an HGBL with MYC and BCL2 rearrangements. The ways in which these cases are distinguished from other lymphomas with high-grade features and the appropriate nomenclature using WHO-5 and ICC classifications are emphasized., Results: An HGBL diagnosis requires integration of morphology, immunophenotype, and genetics and exclusion of other lymphomas with high-grade morphology, including Burkitt lymphoma, B-lymphoblastic leukemia/lymphoma (B-LBL/ALL), and blastoid mantle cell lymphoma. A diagnosis of HGBL/large B-cell lymphoma with 11q aberration should also be considered in certain patient populations., Conclusions: High-grade B-cell lymphomas are subclassified based on morphologic and genetic features. There are differences in the nomenclature and definition of these lymphomas in the WHO-5 and ICC classifications. Distinguishing HGBLs from other mature B-cell lymphomas and B-LBL/ALL is critical so that patients receive appropriate treatment., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Society for Clinical Pathology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background: Nasopharyngeal carcinomas (NPCs) are malignant tumors originating from the lining epithelium of the nasopharynx. Fusion genes have been confirmed to play important roles in the occurrence and development of various malignant tumors, but the role of fusion genes in NPC is poorly understood. We aimed to explore new fusion genes that promote the occurrence and development of NPC. Methods: RNA-seq was used to search for interchromosomal translocations in 18 NPC tissues. Polymerase chain reaction (PCR) and Sanger sequencing were applied to verify the presence of BCL6-SPECC1L (BS); quantitative PCR (qPCR) and Western blotting were used to measure the expression level of BCL-6 in NPC cells; MTT and in vivo tumorigenesis assays were applied to evaluate the cell proliferation ability; immunofluorescence assays were used to determine the cellular localization of BCL6 and BS; and a luciferase reporter assay was performed to evaluate the ability of BCL6 and BS to inhibit transcription. Results: BS was present in 5.34% (11/206) of primary NPC biopsies and 2.13% (1/47) of head and neck cancer biopsies. The expression of BCL6 was downregulated in NPC, and silencing of endogenous BCL6 promoted NPC cell proliferation in vitro. Overexpression of BCL6 but not BS inhibited the growth of NPC cells in vivo and in vitro. Mechanistically, BCL6 localized in the nucleus can inhibit the G1/S transition to suppress the growth of NPC cells. However, after the fusion of BCL6 and SPECC1L, the product cannot localize to the nucleus, and the transcriptional inhibitory function of BCL6 is abolished, eventually abolishing its tumor suppressor effect and leading to the development of NPC. Conclusion: BS is a novel fusion gene in NPC that may play an important role in the occurrence and development of this cancer. The clinical significance of the BS fusion gene needs further elucidation. [ABSTRACT FROM AUTHOR]

Background: Esophageal adenocarcinoma is a lethal disease. For locally advanced patients, neoadjuvant chemoradiotherapy followed by surgery is the standard of care. Risk stratification relies heavily on clinicopathologic features, particularly pathologic response, which is inadequate, therefore establishing the need for new and reliable biomarkers for risk stratification. Methods: Thirty four patients with locally advanced esophageal adenocarcinoma were analyzed, of which 21 received a CROSS regimen with carboplatin, paclitaxel, and radiation. Capture-based targeted sequencing was performed on the paired baseline and post-treatment samples. Differentially mutated gene analysis between responders and non-responders of treatment was performed to determine predictors of response. A univariate Cox proportional hazard regression was used to examine associations between gene mutation status and overall survival. Results: A 3-gene signature, based on mutations in EPHA5, BCL6, and ERBB2, was identified that robustly predicts response to the CROSS regimen. For this model, sensitivity was 84.6% and specificity was 100%. Independently, a 9 gene signature was created using APC, MAP3K6, ETS1, CSF3R, PDGFRB, GATA2, ARID1A, PML, and FGF6, which significantly stratifies patients into risk categories, prognosticating for improved relapse-free (p = 4.73E-03) and overall survival (p = 3.325E-06). The sensitivity for this model was 73.33% and the specificity was 94.74%. Conclusion: We have identified a 3-gene signature (EPHA5, BCL6, and ERBB2) that is predictive of response to neoadjuvant chemoradiotherapy and a separate prognostic 9-gene classifier that predicts survival outcomes. These panels provide significant potential for personalized management of locally advanced esophageal cancer. [ABSTRACT FROM AUTHOR]

Recent studies propose that T follicular helper (Tfh) cells possess a high degree of functional plasticity in addition to their well‐defined roles in mediating interleukin‐4‐dependent switching of germinal center B cells to the production of immunoglobulin (Ig)G1 and IgE antibodies. In particular Tfh cells have been proposed to be an essential stage in Th2 effector cell development that are able to contribute to innate type 2 responses. We used CD4‐cre targeted deletion of BCL6 to identify the contribution Tfh cells make to tissue Th2 effector responses in models of atopic skin disease and lung immunity to parasites. Ablation of Tfh cells did not impair the development or recruitment of Th2 effector subsets to the skin and did not alter the transcriptional expression profile or functional activities of the resulting tissue resident Th2 effector cells. However, the accumulation of Th2 effector cells in lung Th2 responses was partially affected by BCL6 deficiency. These data indicate that the development of Th2 effector cells does not require a BCL6 dependent step, implying Tfh and Th2 effector populations follow separate developmental trajectories and Tfh cells do not contribute to type 2 responses in the skin. [ABSTRACT FROM AUTHOR]