CD20 CAR T cells safely and reversibly ablate B cell follicles in a non-human primate model of HIV persistence.

Chimeric antigen receptor (CAR) T cell therapies have demonstrated immense clinical success for B cell and plasma cell malignancies. We tested their impact on the viral reservoir in a macaque model of HIV persistence, comparing the functions of CD20 CAR T cells between animals infected with simian/human immunodeficiency virus (SHIV) and uninfected controls. We focused on the potential of this approach to disrupt B cell follicles (BCFs), exposing infected cells for immune clearance. In SHIV-infected animals, CAR T cells were highly functional, with rapid expansion and trafficking to tissue-associated viral sanctuaries, including BCFs and gut-associated lymphoid tissue (GALT). CD20 CAR T cells potently ablated BCFs and depleted lymph-node-associated follicular helper T (TFH) cells, with complete restoration of BCF architecture and TFH cells following CAR T cell contraction. BCF ablation decreased the splenic SHIV reservoir but was insufficient for effective reductions in systemic viral reservoirs. Although associated with moderate hematologic toxicity, CD20 CAR T cells were well tolerated in SHIV-infected and control animals, supporting the feasibility of this therapy in people living with HIV with underlying B cell malignancies. Our findings highlight the unique ability of CD20 CAR T cells to safely and reversibly unmask TFH cells within BCF sanctuaries, informing future combinatorial HIV cure strategies designed to augment antiviral efficacy.

Network pharmacology and molecular docking to study the mechanism of action of alpinumisoflavone in a temporomandibular joint osteoarthritis cell model / 口腔疾病防治

Objective@#To explore the potential role of alpinumisoflavone (AIF) in the treatment of temporomandibular joint osteoarthritis (TMJOA) cell model through network pharmacology and molecular docking and to provide a research basis for AIF in the treatment of TMJOA.@*Methods@#GeneCards, OMIM, DisGeNET, and PharmGKB databases were used to screen TMJOA disease targets, and PharmMapper and HERB were used to retrieve AIF-related targets. The intersection targets of the compounds and diseases were uploaded to the STRING database to obtain the key targets for GO and KEGG enrichment analysis, while the key targets in related signaling pathways were evaluated through molecular docking. Approval was obtained from the Ethics Committee to extract condylar chondrocytes from 3-week-old SD rats. The CCK-8 assay was used to detect AIF cytotoxicity on condylar chondrocytes. Condylar chondrocytes were induced with 10 ng/mL interleukin 1β (IL-1β) for 24 h to construct a TMJOA cell model. The experiment was divided into three groups: control group, comprising condylar chondrocytes cultured in DMEM for 48 h; IL-1β group, comprising condylar chondrocytes pre-cultured in DMEM for 24 h, after which IL-1β was added to the original culture medium to obtain a medium concentration of 10 ng/mL and allowed to culture for 24 h; and the IL-1β+10 μmol/L AIF group, comprising condylar chondrocytes pre-cultured in DMEM medium containing 10 μmol/L AIF for 24 h, after which IL-1β was added to the original culture medium to obtain a medium concentration of 10 ng/mL and allowed to culture for 24 h. The effect of AIF on condylar chondrocyte apoptosis in the TMJOA cell model was detected by flow cytometry. The experiment was divided into four groups: control group, IL-1β group, IL-1β+10 μmol/L AIF group, and IL-1β+30 μmol/L AIF group. The IL-1β+30 μmol/L AIF group was pre-cultured in DMEM containing 30 μmol/L AIF for 24 h, after which IL-1β was added to the original culture medium to obtain a medium concentration of 10 ng/mL and allowed to culture for 24 h. The remaining three groups were cultured in the same manner as before. The mRNA and protein expression of apoptosis-associated B-cell leukemia/lymphoma-2 (Bcl2), cysteinyl aspartate specific protease 3 (caspase-3), matrix degradation-associated a disintegrin and metalloproteinase with thrombospondin motifs 4 (ADAMTS4), matrix metalloproteinase 3 (MMP3), and matrix metalloproteinase 13 (MMP13) were detected by qPCR and western blot, by AIF in the TMJOA cell model.@*Results@#The PharmMapper and HERB database search yielded 300 AIF compound targets. The GeneCards, OMIM, DisGeNET, and PharmGKB databases yielded 378 TMJOA disease targets. Thirty-three potential common targets were obtained by intersecting compounds with disease targets. The common targets were uploaded into the STRING database to obtain 31 key targets that were mainly associated with apoptosis and extracellular matrix degradation. This process may be associated with the MAPK, estrogen, and TNF signaling pathways. The molecular docking results showed that AIF has good binding activity with extracellular signal-regulated kinase 1/2 (ERK1/2) and estrogen receptor gene 1/2 (ESR1/2), which are key targets in the MAPK and estrogen signaling pathways. The CCK-8 assay showed that AIF had no obvious cytotoxicity to condylar chondrocytes. The cell experiments showed that AIF inhibited apoptosis in the IL-1β+10 μmol/L AIF group compared to the IL-1β group. Compared to the IL-1β group in the IL-1β+10 μmol/L AIF group and the IL-1β+30 μmol/L AIF group, AIF upregulated Bcl2 and downregulated caspase-3 mRNA and protein expression and inhibited ADAMTS4, MMP3, and MMP13 mRNA and protein expression.@*Conclusion@#AIF inhibited apoptosis in the TMJOA cell model by upregulating Bcl2 and downregulating caspase-3 mRNA and protein expression, and inhibited extracellular matrix degradation induced by IL-1β, thereby delaying TMJOA progression.

TRIM26 promotes non-small cell lung cancer survival by inducing PBX1 degradation.

The transcription factor PBX1 is regarded as an oncogene in various cancers, but its role in non-small cell lung cancer (NSCLC) and the detailed mechanism is not known. In the present study, we found that PBX1 is downregulated in NSCLC tissues and inhibits NSCLC cell proliferation and migration. Subsequently, we performed an affinity purification-coupled tandem mass spectrometry (MS/MS) and found the ubiquitin ligase TRIM26 in the PBX1 immunoprecipitates. Moreover, TRIM26 binds to and mediates PBX1 for K48-linked polyubiquitination and proteasomal degradation. Noticeably, TRIM26 activity depends on its C-terminal RING domain when it is deleted TRIM26 loses its function towards PBX1. TRIM26 further inhibits PBX1 transcriptional activity and downregulates the PBX1 downstream genes, such as RNF6. Moreover, we found that overexpression of TRIM26 significantly promotes NSCLC proliferation, colony formation, and migration in contradiction to PBX1. TRIM26 is highly expressed in NSCLC tissues and predicts poor prognosis. Lastly, the growth NSCLC xenografts is promoted by overexpression of TRIM26 but is suppressed by TRIM26 knockout. In conclusion, TRIM26 is a ubiquitin ligase of PBX1 and it promotes while PBX1 inhibits NSCLC tumor growth. TRIM26 might be a novel therapeutic target for the treatment of NSCLC.

MicroRNA-202-5p-dependent inhibition of Bcl-2 contributes to macrophage apoptosis and atherosclerotic plaque formation.

BACKGROUND: The identification of microRNA (miRNA)-related molecular mechanisms has advanced the development of new therapeutics for atherosclerosis (AS). The roles of miR-202-5p- in the pathogenic mechanisms of AS have not been explored. METHODS: Macrophages were transfected with a series of miR-202-5p mimic/inhibitor, and then assessed for changes in viability, apoptosis, and secretion of inflammatory cytokines. The regulatory mechanism of miR-202-5p was explored through dual-luciferase reporter gene assay. A mouse model of AS was developed in ApoE-/- mice fed with high-fat diet to examine the in vivo effects of miR-202-5p on atherosclerotic plaque formation, collagen synthesis, and fiber cap thickness. RESULTS: Elevated miR-202-5p was found in atherosclerotic plaque tissues of the mice. miR-202-5p was able to induce macrophage apoptosis and release of pro-inflammatory factors. Besides, miR-202-5p limited Bcl-2 expression and elevated the levels of Bax, cleaved caspase-3, and cleaved caspase-9. Bcl-2 was concluded as a target gene of miR-202-5p. The pro-apoptotic effect of miR-202-5p on macrophages was achieved via limiting Bcl-2. In the mouse AS model, restoration of miR-202-5p stimulated atherosclerotic plaque formation, but reduced collagen synthesis and fiber cap thickness. CONCLUSION: These data collectively suggest a pro-apoptotic action of miR-202-5p in macrophages that contributes to atherosclerotic plaque formation.

Phosphorylation of PBX2, a novel downstream target of mTORC1, is determined by GSK3 and PP1.

Mechanistic target of rapamycin complex 1 (mTORC1) is a serine-threonine kinase that is activated by extracellular signals, such as nutrients and growth factors. It plays a key role in the control of various biological processes, such as protein synthesis and energy metabolism by mediating or regulating the phosphorylation of multiple target molecules, some of which remain to be identified. We have here reanalysed a large-scale phosphoproteomics data set for mTORC1 target molecules and identified pre-B cell leukemia transcription factor 2 (PBX2) as such a novel target that is dephosphorylated downstream of mTORC1. We confirmed that PBX2, but not other members of the PBX family, is dephosphorylated in an mTORC1 activity-dependent manner. Furthermore, pharmacological and gene knockdown experiments revealed that glycogen synthase kinase 3 (GSK3) and protein phosphatase 1 (PP1) are responsible for the phosphorylation and dephosphorylation of PBX2, respectively. Our results thus suggest that the balance between the antagonistic actions of GSK3 and PP1 determines the phosphorylation status of PBX2 and its regulation by mTORC1.

Cerebrovascular accident in a child with precursor B-cell acute lymphoblastic leukemia and coronavirus disease 2019: a case report.

BACKGROUND: Coronavirus disease 2019 can lead to rare but severe and life-threatening diseases in susceptible high-risk populations, including patients with immunodeficiency. A rare event in this report is stroke following COVID-19 disease in a patient with an immunocompromised background due to leukemia and anti-cancer treatments. CASE PRESENTATION: A 6-year-old iranian girl with precursor B-cell leukemia receiving vincristine therapy presented with fever and absolute neutrophil count < 500. Her severe acute respiratory syndrome coronavirus 2 polymerase chain reaction test was positive. During hospitalization, she had abrupt onset tachypnea, reduced O2 saturation, and generalized tonic-clonic seizures treated with phenytoin and levetiracetam. Right parietal lobe ischemia was found on a brain computed tomography scan, and the cerebrospinal fluid polymerase chain reaction test was positive for severe acute respiratory syndrome coronavirus 2. Several days later, she developed lower extremity paralysis and speech impairment, so speech therapy and physiotherapy were initiated. The patient also received dexamethasone, mannitol, heparin, and remdesivir. She was discharged with enoxaparin and levetiracetam. Chemotherapy resumed 2 weeks following discharge. Her speech and walking improved after 10 months of follow-up, and bone marrow aspiration showed total remission. CONCLUSION: Owing to the link between coronavirus disease 2019 and hematologic cancers with hypercoagulopathy and the tendency of patients with leukemia to have coronavirus disease 2019 complications, children with leukemia as well as suspected coronavirus disease 2019 must be hospitalized to prevent blood clot formation.

Autologous Anti-CD19 CAR T-Cells immunotherapy in relapsed/refractory acute lymphoblastic leukemia patients. A systematic review and meta-analysis / Imunoterapia de CAR T-Cells Anti-CD19 no tratamento de leucemia linfoblástica aguda refratária/recidivante. Revisão sistemática e metanálise

Introduction: Acute Lymphoblastic Leukemia (ALL) is the most prevalent malignancy in children; however, when the neoplasm becomes refractory/relapses (R/R) the cure possibilities are practically null. Objectives: To analyze the Anti-CD19 Chimeric Antigen Receptors (CAR) T-Cells immunotherapy efficacy in the treatment of R/R ALL, providing evidence about the efficacy and safety of the therapy for the analyzed group. Methods: The study consisted of a systematic review and meta-analysis based on the analysis of indexed articles. The searches were carried out with the terms: "acute lymphoblastic leukemia", "CAR T", and "CD19-specific chimeric antigen receptor". Results: Only 18 of the 94 articles obtained initially met the inclusion criteria and were selected for review, totaling 637 patients. Thus, it was observed in the responses that approximately 81% of the patients achieved a Complete Response; 7% did not respond; the neoplasm relapsed in 17% of the cases; and 6.1% of the patients died. The main side effects found were Cytokine Release Syndrome (CRS), Severe Cytokine Release Syndrome, and Neurotoxicity, present in 36.3%, 29%, and 24% of patients, respectively. Conclusion: Anti-CD19 CAR T-Cells immunotherapy is an effective therapy, capable of producing high rates of complete remission in R/R ALL treatment. [au]

Introdução: A Leucemia Linfoblástica Aguda (LLA) é a neoplasia maligna mais prevalente em crianças; entretanto, quando se torna refratária/recidivante (R/R) as possibilidades de cura são praticamente nulas. Objetivos: Analisar a eficácia da imunoterapia de Receptores de Antígenos Quiméricos anti-CD19 no tratamento da LLA R/R, fornecendo evidências sobre a efetividade e segurança da terapia para o grupo analisado. Métodos: O estudo consistiu em uma revisão sistemática e metanálise baseada em artigos indexados. As pesquisas foram realizadas com os termos: "acute lymphoblastic leukemia", "CAR T", and "CD19-specific chimeric antigen receptor". Resultados: Dos 94 artigos obtidos, apenas 18 atenderam inicialmente aos critérios de inclusão e foram selecionados para revisão, totalizando 637 pacientes. Assim, observou-se nas respostas que aproximadamente 81% dos pacientes obtiveram resposta completa; 7% não responderam; a neoplasia recidivou em 17% dos casos; e 6,1% dos pacientes morreram. Os principais efeitos colaterais encontrados foram síndrome de liberação de citocinas, síndrome de liberação grave de citocinas e neurotoxicidade, presentes em 36,3%, 29% e 24% dos pacientes, respectivamente. Conclusão: A imunoterapia com células CAR T anti-CD19 é uma terapia eficaz, sendo capaz de produzir altas taxas de remissão completa no tratamento de LLA R / R. [au]

BTK, the new kid on the (oncology) block?

In the last decade data piled up indicating that BTK - for twenty years considered as a "private matter" of bone marrow-derived cells - it is expressed and plays important and different roles also outside of the hematopoietic compartment and, most notably, in tumor cells. Initial evidence that BTK plays a critical role in B cell-derived malignancies prompted the chase for specific inhibitors, the forefather of which entered the clinic in a record time and paved the way for an ever increasing number of new molecules to be trialed. The growing interests in BTK also led to the discovery that, in solid tumors, two novel isoforms are mainly expressed and actionable liabilities for target therapy. Remarkably, the different isoforms appear to be involved in different signaling pathways which will have to be attentively specified in order to define the area of therapeutic intervention. In this perspective we briefly summarize the progress made in the last decade in studying BTK and its isoforms in cancer cells and define the open questions to be addressed in order to get the most benefits from its targeting for therapeutic purposes.

Integrative RNA profiling of TBEV-infected neurons and astrocytes reveals potential pathogenic effectors.

Tick-borne encephalitis virus (TBEV), the most medically relevant tick-transmitted flavivirus in Eurasia, targets the host central nervous system and frequently causes severe encephalitis. The severity of TBEV-induced neuropathogenesis is highly cell-type specific and the exact mechanism responsible for such differences has not been fully described yet. Thus, we performed a comprehensive analysis of alterations in host poly-(A)/miRNA/lncRNA expression upon TBEV infection in vitro in human primary neurons (high cytopathic effect) and astrocytes (low cytopathic effect). Infection with severe but not mild TBEV strain resulted in a high neuronal death rate. In comparison, infection with either of TBEV strains in human astrocytes did not. Differential expression and splicing analyses with an in silico prediction of miRNA/mRNA/lncRNA/vd-sRNA networks found significant changes in inflammatory and immune response pathways, nervous system development and regulation of mitosis in TBEV Hypr-infected neurons. Candidate mechanisms responsible for the aforementioned phenomena include specific regulation of host mRNA levels via differentially expressed miRNAs/lncRNAs or vd-sRNAs mimicking endogenous miRNAs and virus-driven modulation of host pre-mRNA splicing. We suggest that these factors are responsible for the observed differences in the virulence manifestation of both TBEV strains in different cell lines. This work brings the first complex overview of alterations in the transcriptome of human astrocytes and neurons during the infection by two TBEV strains of different virulence. The resulting data could serve as a starting point for further studies dealing with the mechanism of TBEV-host interactions and the related processes of TBEV pathogenesis.

Spontaneous Hind Limb Paralysis Due to Acute Precursor B Cell Leukemia in RAG1-deficient Mice.

RAG1-deficient mice are a frequently used immunodeficient mouse strain lacking mature lymphocytes. Apart from an elevated risk for infections, no predispositions for diseases of this strain have been described so far. We here report a high incidence of spontaneous pro B cell leukemia resulting in hind limb paralysis in our colony of RAG1-deficient mice. At an age of 7-13 months, animals developed hind limb paralysis and rapid decrease of the overall health condition leading to the need of euthanasia. Histological and flow cytometric analyses as well as micro-computed tomography (micro-CT) scans revealed CD45+ CD19+ IgM- cell infiltrates in the spleen, the bone marrow, and the spinal canal. Monthly blood sampling and screening for CD19+ blast frequency in the peripheral blood was successfully established for monitoring of leukemia development before symptom onset. We conclude that facilities that breed RAG1-deficient mice should be aware of the risk of leukemia development in this strain and recommend to implement regular blood sampling for aged RAG1-deficient animals.

Infectious Complications in Pediatric, Adolescent and Young Adult Patients Undergoing CD19-CAR T Cell Therapy.

CD19-specific chimeric antigen receptor (CAR) T cell therapy has changed the treatment paradigm for pediatric, adolescent and young adult (AYA) patients with relapsed/refractory B-cell acute lymphoblastic leukemia (B-ALL). However, data on the associated infectious disease challenges in this patient population are scarce. Knowledge of infections presenting during treatment, and associated risk factors, is critical for pediatric cellular therapy and infectious disease specialists as we seek to formulate effective anti-infective prophylaxis, infection monitoring schemas, and empiric therapy regimens. In this work we describe our institutional experience in a cohort of 38 pediatric and AYA patients with CD19-positive malignancy treated with lymphodepleting chemotherapy (fludarabine/cyclophosphamide) followed by a single infusion of CD19-CAR T cells (total infusions, n=39), including tisagenlecleucel (n=19; CD19/4-1BB) or on an institutional clinical trial (n=20; CD19/4-1BB; NCT03573700). We demonstrate that infections were common in the 90 days post CAR T cells, with 19 (50%) patients experiencing a total of 35 infections. Most of these (73.7%) occurred early post infusion (day 0 to 28; infection density of 2.36 per 100 patient days-at-risk) compared to late post infusion (day 29 to 90; infection density 0.98 per 100 patient days-at-risk), respectively. Bacterial infections were more frequent early after CAR T cell therapy, with a predominance of bacterial blood stream infections. Viral infections occurred throughout the post infusion period and included primarily systemic reactivations and gastrointestinal pathogens. Fungal infections were rare. Pre-infusion disease burden, intensity of bridging chemotherapy, lymphopenia post lymphodepleting chemotherapy/CAR T cell infusion and development of CAR-associated hemophagocytic lymphohistiocytosis (carHLH) were all significantly associated with either infection density or time to first infection post CAR T cell infusion. A subset of patients (n=6) had subsequent CAR T cell reinfusion and did not appear to have increased risk of infectious complications. Our experience highlights the risk of infections after CD19-CAR T cell therapy, and the need for continued investigation of infectious outcomes as we seek to improve surveillance, prophylaxis and treatment algorithms.

The Enhanced Cytotoxic Effects in B-Cell Leukemia and Lymphoma Following Activation of Prostaglandin EP4 Receptor and Targeting of CD20 Antigen by Monoclonal Antibodies.

Anti-CD20 monoclonal antibodies (MAbs) have revolutionized the treatment of B-cell leukemia and lymphoma. However, many patients do not respond to such treatment due to either deficiency of the complementary immune response or resistance to apoptosis. Other currently available treatments are often inadequate or induce major side effects. Therefore, there is a constant need for improved therapies. The prostaglandin E2 receptor 4 (EP4) receptor has been identified as a promising therapeutic target for hematologic B-cell malignancies. Herein, we report that EP4 receptor agonists PgE1-OH and L-902688 have exhibited enhanced cytotoxicity when applied together with anti-CD20 MAbs rituximab, ofatumumab and obinutuzumab in vitro in Burkitt lymphoma cells Ramos, as well as in p53-deficient chronic lymphocytic leukemia (CLL) cells MEC-1. Moreover, the enhanced cytotoxic effects of EP4 receptor agonists and MAbs targeting CD20 have been identified ex vivo on primary lymphocytes B obtained from patients diagnosed with CLL. Incubation of cells with PgE1-OH and L-902688 preserved the expression of CD20 molecules, further confirming the anti-leukemic potential of EP4 receptor agonists in combination with anti-CD20 MAbs. Additionally, we demonstrated that the EP4 receptor agonist PgE-1-OH induced apoptosis and inhibited proliferation via the EP4 receptor triggering in CLL. This work has revealed very important findings leading towards the elucidation of the anticancer potential of PgE1-OH and L-902688, either alone or in combination with MAbs. This may contribute to the development of potential therapeutic alternatives for patients with B-cell malignancies.

Alteration of the immune environment in bone marrow from children with recurrent B cell precursor acute lymphoblastic leukemia.

Due to the considerable success of cancer immunotherapy for leukemia, the tumor immune environment has become a focus of intense research; however, there are few reports on the dynamics of the tumor immune environment in leukemia. Here, we analyzed the tumor immune environment in pediatric B cell precursor acute lymphoblastic leukemia by analyzing serial bone marrow samples from nine patients with primary and recurrent disease by mass cytometry using 39 immunophenotype markers, and transcriptome analysis. High-dimensional single-cell mass cytometry analysis elucidated a dynamic shift of T cells from naïve to effector subsets, and clarified that, during relapse, the tumor immune environment comprised a T helper 1-polarized immune profile, together with an increased number of effector regulatory T cells. These results were confirmed in a validation cohort using conventional flow cytometry. Furthermore, RNA transcriptome analysis identified the upregulation of immune-related pathways in B cell precursor acute lymphoblastic leukemia cells during relapse, suggesting interaction with the surrounding environment. In conclusion, a tumor immune environment characterized by a T helper 1-polarized immune profile, with an increased number of effector regulatory T cells, could contribute to the pathophysiology of recurrent B cell precursor acute lymphoblastic leukemia. This information could contribute to the development of effective immunotherapeutic approaches against B cell precursor acute lymphoblastic leukemia relapse.

Novel targeted treatments in hairy cell leukemia and other hairy cell-like disorders.

In the category of mature B-cell neoplasms, splenic B-cell lymphoma and leukemia were clearly identified and include four distinct entities: hairy cell leukemia (HCL), splenic marginal zone lymphoma (SMZL), splenic diffuse red pulp lymphoma (SDRPL) and the new entity named splenic B-cell lymphoma/leukemia with prominent nucleoli (SBLPN). The BRAFV600E mutation is detected in nearly all HCL cases and offers a possibility of targeted therapy. BRAF inhibitors (BRAFi) represent effective and promising therapeutic approaches in patients with relapsed/refractory HCL. Vemurafenib and dabrafenib were assessed in clinical trials. The BRAFV600E mutation is missing in SDRPL and SBLPN: mitogen-activated protein kinase 1 (MAP2K1) mutations were found in 40% of SBLPN and VH4-34+ HCL patients, making possible to use MEK inhibitors (MEKi) such as trametinib, cobimetinib or binimetinib in monotherapy or associated with BRAFi. Other mutations may be associated and other signaling pathways involved, including the B-cell receptor signaling (BCR), cell cycle, epigenetic regulation and/or chromatin remodeling. In SDRPL, cyclin D3 (CCND3) mutations were found in 24% of patients, offering the possibility of using cell cycle inhibitors. Even if new emerging drugs, particularly those involved in the epigenetic regulation, have recently been added to the therapeutic armamentarium in HCL and HCL-like disorders, purine nucleoside analogs more and more associated with anti-CD20 monoclonal antibodies, are still used in the frontline setting. Thanks to the recent discoveries in genetics and signaling pathways in HCL and HCL-like disorders, new targeted therapies have been developed, have proven their efficacy and safety in several clinical trials and become essential in real life: BRAFi, MEKi, Bruton Tyrosine Kinase inhibitors (BTKi) and anti-CD22 immunotoxins. New other drugs emerged and have to be assessed in the future. In this article, we will discuss the main mutations identified in HCL and HCL-like disorders and the signaling pathways potentially involved in the pathogenesis of the different hairy cell disorders. We will discuss the results of the recent clinical trials, which will help us to propose an algorithm useful in clinical practice and we will highlight the different new drugs that may be used in the near future.

Overexpression and clinical significance of PBX3 in acute myeloid leukemia / 安徽医科大学学报

Objective @#To investigate the expression levels and potential clinical significance of pre-B-cell leukemia homologous box 3 (PBX3) in bone marrow samples from acute myeloid leukemia (AML) .@*Methods @#The mRNA expression levels of PBX3 were determined by bioinformatics which analyzed the RNAseq data of 33 malignancies from the cancer genome atlasdatabase． (TCGA) The correlations among the expression levels of PBX3，the clinical parameters and prognosis of AML patients were further analyzed．The differentially expressed genes in the whole transcriptome were analyzed to identify the molecular network in AML caused by PBX3 expression abnormalities. @*Results @#The mRNA expression levels of PBX3 were up-regulated in 12 malignancies，and the altitudes increased most significantly in AML than any other cancer types．Patients with high PBX3 expression showed shorter overall survival and disease-free survival than patients with low PBX3 expression．High PBX3 expression was significantly associated with FLT3，NPM1，and DNMT3A mutation．PBX3 expression was positively correlated with multiple ho- meobox genes (including most HOXA and HOXB genes ，MEIS1 ) ，and the expression levels of these homeobox genes were all negatively correlated with AML patients overall survival．@*Conclusion @#PBX3 high expression in the bone marrow of AML patients is a potential biomarker for poor prognosis ，and it may have extensive interactions with other homeobox genes.

Corrigendum: Histone Deacetylase 3 Aggravates Type 1 Diabetes Mellitus by Inhibiting Lymphocyte Apoptosis Through the microRNA-296-5p/Bcl-xl Axis.

[This corrects the article DOI: 10.3389/fgene.2020.536854.].

Forward and Reverse Genetics of B Cell Malignancies: From Insertional Mutagenesis to CRISPR-Cas.

Cancer genome sequencing has identified dozens of mutations with a putative role in lymphomagenesis and leukemogenesis. Validation of driver mutations responsible for B cell neoplasms is complicated by the volume of mutations worthy of investigation and by the complex ways that multiple mutations arising from different stages of B cell development can cooperate. Forward and reverse genetic strategies in mice can provide complementary validation of human driver genes and in some cases comparative genomics of these models with human tumors has directed the identification of new drivers in human malignancies. We review a collection of forward genetic screens performed using insertional mutagenesis, chemical mutagenesis and exome sequencing and discuss how the high coverage of subclonal mutations in insertional mutagenesis screens can identify cooperating mutations at rates not possible using human tumor genomes. We also compare a set of independently conducted screens from Pax5 mutant mice that converge upon a common set of mutations observed in human acute lymphoblastic leukemia (ALL). We also discuss reverse genetic models and screens that use CRISPR-Cas, ORFs and shRNAs to provide high throughput in vivo proof of oncogenic function, with an emphasis on models using adoptive transfer of ex vivo cultured cells. Finally, we summarize mouse models that offer temporal regulation of candidate genes in an in vivo setting to demonstrate the potential of their encoded proteins as therapeutic targets.

Enhancing B-Cell Malignancies-On Repurposing Enhancer Activity towards Cancer.

B-cell lymphomas and leukemias derive from B cells at various stages of maturation and are the 6th most common cancer-related cause of death. While the role of several oncogenes and tumor suppressors in the pathogenesis of B-cell neoplasms was established, recent research indicated the involvement of non-coding, regulatory sequences. Enhancers are DNA elements controlling gene expression in a cell type- and developmental stage-specific manner. They ensure proper differentiation and maturation of B cells, resulting in production of high affinity antibodies. However, the activity of enhancers can be redirected, setting B cells on the path towards cancer. In this review we discuss different mechanisms through which enhancers are exploited in malignant B cells, from the well-studied translocations juxtaposing oncogenes to immunoglobulin loci, through enhancer dysregulation by sequence variants and mutations, to enhancer hijacking by viruses. We also highlight the potential of therapeutic targeting of enhancers as a direction for future investigation.

HOXA11-AS induces cisplatin resistance by modulating the microRNA-98/PBX3 axis in nasopharyngeal carcinoma.

Long non-coding RNA homeobox A11-antisense RNA (HOXA11-AS) has been implicated in cisplatin (DDP) resistance in multiple types of cancer. The purpose of the present study was to investigate the role of HOXA11-AS in DDP-resistant nasopharyngeal carcinoma (NPC) cells. The expression levels of HOXA11-AS were examined using reverse transcription-quantitative PCR. Cell viability was measured using a Cell Counting Kit-8 assay, and a TUNEL assay was utilized to assess cell apoptosis. The expression levels of apoptosis-related factors (Bax and Bcl-2) were detected by western blot analysis. The interaction between microRNA-98 (miR-98) and HOXA11-AS or pre-B-cell leukemia homeobox 3 (PBX3) was demonstrated using bioinformatics analysis, dual-luciferase reporter assays and RNA immunoprecipitation assays. HOXA11-AS and PBX3 expressions levels were upregulated, whereas miR-98 levels were downregulated in DDP-resistant NPC tissues. Patients with NPC with high HOXA11-AS expression had a low survival rate. Knockdown of HOXA11-AS enhanced the DDP sensitivity of DDP-resistant NPC (5-8F/DDP and SUNE1/DDP) cells, which was demonstrated by the accelerated apoptosis. In addition, HOXA11-AS inhibited the expression levels of miR-98 through direct interaction. Furthermore, miR-98 inhibition counteracted the inductive effect of HOXA11-AS-knockdown on the DDP sensitivity of NPC cells. PBX3 was a target of miR-98 and was positively modulated by HOXA11-AS. Overexpression of PBX3 reversed the suppressive effect of HOXA11-AS silencing on the DDP resistance of NPC cells. The data demonstrated that HOXA11-AS enhanced DDP resistance in NPC via the miR-98/PBX3 axis, providing a potential therapeutic target for patients with DDP-resistant NPC.