TNF-α-dependent hematopoiesis following Bcl11b deletion in T cells restricts metastatic melanoma

Network-based analysis of heterogeneous patient-matched brain and extracranial melanoma metastasis pairs reveals three homogeneous subgroups

Melanoma, the deadliest form of skin cancer, can metastasize to different organs. Molecular differences between brain and extracranial melanoma metastases are poorly understood. Here, promoter methylation and gene expression of 11 heterogeneous patient-matched pairs of brain and extracranial metastases were analyzed using melanoma-specific gene regulatory networks learned from public transcriptome and methylome data followed by network-based impact propagation of patient-specific alterations. This innovative data analysis strategy allowed to predict potential impacts of patient-specific driver candidate genes on other genes and pathways. The patient-matched metastasis pairs clustered into three robust subgroups with specific downstream targets with known roles in cancer, including melanoma (SG1: RBM38, BCL11B, SG2: GATA3, FES, SG3: SLAMF6, PYCARD). Patient subgroups and ranking of target gene candidates were confirmed in a validation cohort. Summarizing, computational network-based impact analyses of heterogeneous metastasis pairs predicted individual regulatory differences in melanoma brain metastases, cumulating into three consistent subgroups with specific downstream target genes.

Case Report and Review of the Literature: Congenital Diaphragmatic Hernia and Craniosynostosis, a Coincidence or Common Cause?

Congenital diaphragmatic hernia (CDH) is a life-threatening birth defect that presents as either an isolated diaphragm defect or as part of a complex disorder with a wide array of anomalies (complex CDH). Some patients with complex CDH display distinct craniofacial anomalies such as craniofrontonasal dysplasia or craniosynostosis, defined by the premature closure of cranial sutures. Using clinical whole exome sequencing (WES), we found a BCL11B missense variant in a patient with a left-sided congenital diaphragmatic hernia as well as sagittal suture craniosynostosis. We applied targeted sequencing of BCL11B in patients with craniosynostosis or with a combination of craniosynostosis and CDH. This resulted in three additional BCL11B missense mutations in patients with craniosynostosis. The phenotype of the patient with both CDH as well as craniosynostosis was similar to the phenotype of previously reported patients with BCL11B missense mutations. Although these findings imply that both craniosynostosis as well as CDH may be associated with BCL11B mutations, further studies are required to establish whether BCL11B variants are causative mutations for both conditions or if our finding was coincidental.

BCL11B suppresses tumor progression and stem cell traits in hepatocellular carcinoma by restoring p53 signaling activity

Accumulating evidence indicates that hepatocellular carcinoma (HCC) tumorigenesis, recurrence, metastasis, and therapeutic resistance are strongly associated with liver cancer stem cells (CSCs), a rare subpopulation of highly tumorigenic cells with self-renewal capacity and differentiation potential. Previous studies identified B cell leukemia/lymphoma-11b (BCL11B) as a novel tumor suppressor with impressive capacity to restrain CSC traits. However, the implications of BCL11B in HCC remain unclear. In this study, we found that low BCL11B expression was an independent indicator for shorter overall survival (OS) and time to recurrence (TTR) for HCC patients with surgical resection. In vitro and in vivo experiments confirmed BCL11B as a tumor suppressor in HCC with inhibitory effects on proliferation, cell cycle progression, apoptosis, and mobility. Furthermore, BCL11B could suppress CSC traits, as evidenced by dramatically decreased tumor spheroid formation, self-renewal potential and drug resistance. A Cignal Finder Array and dual-luciferase activity reporter assays revealed that BCL11B could activate the transcription of P73 via an E2F1-dependent manner. Thus, we concluded that BCL11B is a strong suppressor of retaining CSC traits in HCC. Ectopic expression of BCL11B might be a promising strategy for anti-HCC treatment with the potential to cure HBV-related HCC regardless of P53 mutation status.

Impact of Injury Severity on the Inflammatory State and Severe Anemia

BACKGROUND

Severe traumatic injury is a major cause of morbidity and mortality. Our goal was to analyze blunt traumatic injury by injury severity score (ISS) and compare with elective hip repair, as a transient injury, and healthy control with the hypothesis that more severe injury would lead to an increase in neuroendocrine activation, systemic inflammation, and worse anemia.

MATERIALS AND METHODS

A prospective observational cohort study was performed at a level 1 trauma center, comparing blunt trauma patients (n = 37), elective hip replacement patients (n = 26), and healthy controls (n = 8). Bone marrow and plasma were assessed for hyperadrenergic state, erythropoiesis, and systemic inflammation. Trauma patient's ISS ranged from 4 to 41 and were broken down into quartiles for analysis. The ISS quartiles were 4-13, 14-20, 21-26, and 27-41.

RESULTS

Plasma norepinephrine, interleukin-6, tumor necrosis factor-alpha, and hepcidin increased progressively as ISS increased. Hemoglobin significantly decreased as ISS increased and packed red blood cell (pRBC) transfusion increased as ISS increased. Elective hip replacement patients had an appropriate increase in the bone marrow expression of erythropoietin and the erythropoietin receptor, which was absent in all trauma patient groups.

CONCLUSIONS

Increased neuroendocrine activation, systemic inflammation, and anemia correlated with worsening injury severity, lower age, and increased pRBC transfusions. Elective hip replacement patients have only minimal systemic inflammation with an appropriate bone marrow response to anemia. This study demonstrates a link between injury severity, neuroendocrine activation, systemic inflammation, and the bone marrow response to anemia.

Effect of Beta-Blockade on the Expression of Regulatory MicroRNA after Severe Trauma and Chronic Stress

BACKGROUND

Beta-blockade administration after lung contusion, hemorrhagic shock, and chronic stress has been shown to improve bone marrow function, decrease hypercatecholaminemia, and reduce inflammation. MicroRNAs (miR) are critical biologic regulators that can downregulate gene expression by causing messenger RNA degradation or inhibition of translation. This study sought to expand our understanding of the molecular mechanisms underlying the reduced inflammatory response after the administration of beta-blockade (BB) in our rodent trauma model.

STUDY DESIGN

Male Sprague-Dawley rats aged 8 to 9 weeks were randomized to lung contusion, hemorrhagic shock with daily restraint stress (LCHS/CS) or LCHS/CS plus propranolol (LCHS/CS+BB). Restraint stress occurred 2 hours daily after LCHS. Propranolol (10 mg/kg) was given daily until day 7. Total RNA and miR were isolated from bone marrow and genome-wide miR expression patterns were assayed. Bone marrow cytokine expression was determined with quantitative polymerase chain reaction.

RESULTS

LCHS/CS led to significantly increased bone marrow expression of interleukin (IL) 1β, tumor necrosis factor-α, IL-6, nitric oxide, and plasma C-reactive protein. There were marked differences in expression of 45 miRs in the LCHS/CS+BB group compared with the LCHS/CS group when using a p value <0.001. Rno-miR-27a and miR-25 were upregulated 7- to 8-fold in the rodents who underwent LCHS/CS+BB compared with LCHS/CS alone, and this correlated with reduced bone marrow expression of IL-1β, tumor necrosis factor-α, IL-6, nitric oxide, and reduced plasma C-reactive protein in the LCHS/CS+BB group.

CONCLUSIONS

The genomic and miR expression patterns in bone marrow after LCHS/CS differed significantly compared with rodents that received propranolol after LCHS/CS. The use of BB after severe trauma can help mitigate persistent inflammation by upregulating Rno-miR-27a and miR-25 and reducing inflammatory cytokines in those who remain critically ill.

A de novo substitution in BCL11B leads to loss of interaction with transcriptional complexes and craniosynostosis

Craniosynostosis, the premature ossification of cranial sutures, is a developmental disorder of the skull vault, occurring in approximately 1 in 2250 births. The causes are heterogeneous, with a monogenic basis identified in ~25% of patients. Using whole-genome sequencing, we identified a novel, de novo variant in BCL11B, c.7C>A, encoding an R3S substitution (p.R3S), in a male patient with coronal suture synostosis. BCL11B is a transcription factor that interacts directly with the nucleosome remodelling and deacetylation complex (NuRD) and polycomb-related complex 2 (PRC2) through the invariant proteins RBBP4 and RBBP7. The p.R3S substitution occurs within a conserved amino-terminal motif (RRKQxxP) of BCL11B and reduces interaction with both transcriptional complexes. Equilibrium binding studies and molecular dynamics simulations show that the p.R3S substitution disrupts ionic coordination between BCL11B and the RBBP4-MTA1 complex, a subassembly of the NuRD complex, and increases the conformational flexibility of Arg-4, Lys-5 and Gln-6 of BCL11B. These alterations collectively reduce the affinity of BCL11B p.R3S for the RBBP4-MTA1 complex by nearly an order of magnitude. We generated a mouse model of the BCL11B p.R3S substitution using a CRISPR-Cas9-based approach, and we report herein that these mice exhibit craniosynostosis of the coronal suture, as well as other cranial sutures. This finding provides strong evidence that the BCL11B p.R3S substitution is causally associated with craniosynostosis and confirms an important role for BCL11B in the maintenance of cranial suture patency.

A CD40 Agonist and PD-1 Antagonist Antibody Reprogram the Microenvironment of Nonimmunogenic Tumors to Allow T-cell-Mediated Anticancer Activity

In cancers with tumor-infiltrating lymphocytes (TILs), monoclonal antibodies (mAbs) that block immune checkpoints such as CTLA-4 and PD-1/PD-L1 promote antitumor T-cell immunity. Unfortunately, most cancers fail to respond to single-agent immunotherapies. T regulatory cells, myeloid derived suppressor cells (MDSCs), and extensive stromal networks within the tumor microenvironment (TME) dampen antitumor immune responses by preventing T-cell infiltration and/or activation. Few studies have explored combinations of immune-checkpoint antibodies that target multiple suppressive cell populations within the TME, and fewer have studied the combinations of both agonist and antagonist mAbs on changes within the TME. Here, we test the hypothesis that combining a T-cell-inducing vaccine with both a PD-1 antagonist and CD40 agonist mAbs (triple therapy) will induce T-cell priming and TIL activation in mouse models of nonimmunogenic solid malignancies. In an orthotopic breast cancer model and both subcutaneous and metastatic pancreatic cancer mouse models, only triple therapy was able to eradicate most tumors. The survival benefit was accompanied by significant tumor infiltration of IFNγ-, Granzyme B-, and TNFα-secreting effector T cells. Further characterization of immune populations was carried out by high-dimensional flow-cytometric clustering analysis and visualized by t-distributed stochastic neighbor embedding (t-SNE). Triple therapy also resulted in increased infiltration of dendritic cells, maturation of antigen-presenting cells, and a significant decrease in granulocytic MDSCs. These studies reveal that combination CD40 agonist and PD-1 antagonist mAbs reprogram immune resistant tumors in favor of antitumor immunity.

A novel CBL-Bflox/flox mouse model allows tissue-selective fully conditional CBL/CBL-B double-knockout: CD4-Cre mediated CBL/CBL-B deletion occurs in both T-cells and hematopoietic stem cells

CBL-family ubiquitin ligases are critical negative regulators of tyrosine kinase signaling, with a clear redundancy between CBL and CBL-B evident in the immune cell and hematopoietic stem cell studies. Since CBL and CBL-B are negative regulators of immune cell activation, elimination of their function to boost immune cell activities could be beneficial in tumor immunotherapy. However, mutations of CBL are associated with human leukemias, pointing to tumor suppressor roles of CBL proteins; hence, it is critical to assess the tumor-intrinsic roles of CBL and CBL-B in cancers. This has not been possible since the only available whole-body CBL-B knockout mice exhibit constitutive tumor rejection. We engineered a new CBL-Bflox/flox mouse, combined this with an existing CBLflox/flox mouse to generate CBLflox/flox; CBL-Bflox/flox mice, and tested the tissue-specific concurrent deletion of CBL and CBL-B using the widely-used CD4-Cre transgenic allele to produce a T-cell-specific double knockout. Altered T-cell development, constitutive peripheral T-cell activation, and a lethal multi-organ immune infiltration phenotype largely resembling the previous Lck-Cre driven floxed-CBL deletion on a CBL-B knockout background establish the usefulness of the new model for tissue-specific CBL/CBL-B deletion. Unexpectedly, CD4-Cre-induced deletion in a small fraction of hematopoietic stem cells led to expansion of certain non-T-cell lineages, suggesting caution in the use of CD4-Cre for T-cell-restricted gene deletion. The establishment of a new model of concurrent tissue-selective CBL/CBL-B deletion should allow a clear assessment of the tumor-intrinsic roles of CBL/CBL-B in non-myeloid malignancies and help test the potential for CBL/CBL-B inactivation in immunotherapy of tumors.

Essential role of microRNA-650 in the regulation of B-cell CLL/lymphoma 11B gene expression following transplantation: A novel mechanism behind the acute rejection of renal allografts

Kidney transplantation is an effective final therapeutic procedure for patients with end-stage kidney failure. Although advanced immunosuppressive therapy is administered following transplantation, certain patients still suffer from acute allograft rejection. MicroRNAs (miRs) have a potential diagnostic and therapeutic value for acute renal allograft rejection; however, their underlying mechanism of action is largely unknown. In the present study, an increased level of miR-650 was identified to be associated with the downregulation of B-cell CLL/lymphoma 11B (BCL11B) expression in acute renal allograft rejection. Furthermore, in vitro study using human renal glomerular endothelial cells (HRGECs) transfected with a miR-650 mimic revealed that key characteristics of acute renal allograft rejection were observed, including apoptosis, the release of cytokines and the chemotaxis of macrophages, while the effects were reduced in HRGECs transfected with a miR-650 inhibitor. The existence of a conserved miR-650 binding site on the 3'-untranslated region of BCL11B mRNA was predicted by computational algorithms and confirmed by a luciferase reporter assay. Knockdown of BCL11B with small interfering RNA (siRNA) significantly increased the apoptotic rate and significantly decreased the proliferation ability of HRGECs compared with the negative control group. HRGECs transfected with a combination of BCL11B siRNA and the miR-650 mimic demonstrated a significant increase in the rate of apoptosis compared with the control. These results suggest that the upregulation of miR-650 contributes to the development of acute renal allograft rejection by suppression of BCL11B, which leads to apoptosis and inflammatory responses. Thus, miR-650 and BCL11B may represent potential therapeutic targets for the prevention of acute renal allograft rejection.

Targeting CD147 for T to NK Lineage Reprogramming and Tumor Therapy

CD147 is highly expressed on the surface of numerous tumor cells to promote invasion and metastasis. Targeting these cells with CD147-specific antibodies has been validated as an effective approach for lung and liver cancer therapy. In the immune system, CD147 is recognized as a co-stimulatory receptor and impacts the outcome of thymic selection. Using T cell-specific deletion, we showed here that in thymus CD147 is indispensable for the stable αβ T cell lineage commitment: loss of CD147 biases both multipotent DN (double negative) and fully committed DP (double positive) cells into innate NK-like lineages. Mechanistically, CD147 deficiency results in impaired Wnt signaling and expression of BCL11b, a master transcription factor in determining T cell identity. In addition, functional blocking of CD147 by antibody phenocopies genetic deletion to enrich NK-like cells in the periphery. Furthermore, using a melanoma model and orthotopic liver cancer transplants, we showed that the augmentation of NK-like cells strongly associates with resistance against tumor growth upon CD147 suppression. Therefore, besides its original function in tumorigenesis, CD147 is also an effective surface target for immune modulation in tumor therapy.

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DN, DP cells were reprogrammed into innate NK-like cells after thymic CD147 deleted

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Loss of CD147 results in impaired Bcl11b expression and T-lineages development, which can be rescued by Wnt3a stimulation.

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CD147 is an vital target for immune modulation via NK-like cells in tumor therapy.

Tumor therapy is a difficult task and many methods have been used. Among them, tumor immunotherapy is a focus in the field and has made great progress. In this study, we found CD147 is an vital target for immune modulation via NK-like cells in tumor therapy, which means CD147 antibody may be through regulating immune cells to achieve tumor therapy. Although CD147 antibody has been used for liver cancer, making clear the mechanism of CD147 antibody mediated tumor therapy may be benefit for guiding clinical treatment.

Chromatin Remodeling Protein SMAR1 Is a Critical Regulator of T Helper Cell Differentiation and Inflammatory Diseases

T cell differentiation from naïve T cells to specialized effector subsets of mature cells is determined by the iterative action of transcription factors. At each stage of specific T cell lineage differentiation, transcription factor interacts not only with nuclear proteins such as histone and histone modifiers but also with other factors that are bound to the chromatin and play a critical role in gene expression. In this review, we focus on one of such nuclear protein known as tumor suppressor and scaffold matrix attachment region-binding protein 1 (SMAR1) in CD4⁺ T cell differentiation. SMAR1 facilitates Th1 differentiation by negatively regulating T-bet expression via recruiting HDAC1–SMRT complex to its gene promoter. In contrast, regulatory T (T_reg) cell functions are dependent on inhibition of Th17-specific genes mainly IL-17 and STAT3 by SMAR1. Here, we discussed a critical role of chromatin remodeling protein SMAR1 in maintaining a fine-tuned balance between effector CD4⁺ T cells and T_reg cells by influencing the transcription factors during allergic and autoimmune inflammatory diseases.

Intracellularly Swollen Polypeptide Nanogel Assists Hepatoma Chemotherapy

Nowadays, chemotherapy is one of the principal modes of treatment for tumor patients. However, the traditional formulations of small molecule drugs show short circulation time, low tumor selectivity, and high toxicity to normal tissues. To address these problems, a facilely prepared, and pH and reduction dual-responsive polypeptide nanogel was prepared for selectively intracellular delivery of chemotherapy drug. As a model drug, doxorubicin (DOX) was loaded into the nanogel through a sequential dispersion and dialysis technique, resulting in a high drug loading efficiency (DLE) of 96.7 wt.%. The loading nanogel, defined as NG/DOX, exhibited a uniform spherical morphology with a mean hydrodynamic radius of 58.8 nm, pH and reduction dual-triggered DOX release, efficient cell uptake, and cell proliferation inhibition in vitro. Moreover, NG/DOX exhibited improved antitumor efficacy toward H22 hepatoma-bearing BALB/c mouse model compared with free DOX·HCl. Histopathological and immunohistochemical analyses were implemented to further confirm the tumor suppression activity of NG/DOX. Furthermore, the variations of body weight, histopathological morphology, bone marrow cell micronucleus rate, and white blood cell count verified that NG/DOX showed excellent safety in vivo. With these excellent properties in vitro and in vivo, the pH and reduction dual-responsive polypeptide nanogel exhibits great potential for on-demand intracellular delivery of antitumor drug, and holds good prospect for future clinical application.

Haploinsufficiency of Bcl11b suppresses the progression of ATM-deficient T cell lymphomas

Bcl11b is a transcription factor important for T cell development and also a tumor-suppressor gene that is hemizygously inactivated in ~10% human T cell acute lymphoblastic leukemia (T-ALL) and several murine T-ALL models, including ATM(-/-) thymic lymphomas. Here we report that heterozygous loss of Bcl11b (Bcl11b(+/-)) unexpectedly reduced lethal thymic lymphoma in ATM(-/-) mice by suppressing lymphoma progression, but not initiation. The suppression was associated with a T cell-mediated immune response in ATM(-/-)Bcl11b(+/-) mice, revealing a haploid insufficient function of Bcl11b in immune modulation against lymphoma and offering an explanation for the complex relationship between Bcl11b status with T-ALL prognosis.

Transcription Factor Bcl11b Controls Identity and Function of Mature Type 2 Innate Lymphoid Cells

Type 2 innate lymphoid cells (ILC2s) promote anti-helminth responses and contribute to allergies. Here, we report that Bcl11b, previously considered a T-cell-specific transcription factor, acted directly upstream of the key ILC2 transcription factor Gfi1 to maintain its expression in mature ILC2s. Consequently, Bcl11b(-/-) ILC2s downregulated Gata3 and downstream genes, including Il1rl1 (encoding IL-33 receptor), and upregulated Rorc and type 3 ILC (ILC3) genes. Additionally, independent of Gfi1, Bcl11b directly repressed expression of the gene encoding the ILC3 transcription factor Ahr, further contributing to silencing of ILC3 genes in ILC2s. Thus, Bcl11b(-/-) ILC2s lost their functions and gained ILC3 functions, and although they expanded in response to the protease allergen papain, they produced ILC3 but not ILC2 cytokines and caused increased airway infiltration of neutrophils instead of eosinophils. Our results demonstrate that Bcl11b is more than just a T-cell-only transcription factor and establish that Bcl11b sustains mature ILC2 genetic and functional programs and lineage fidelity.

The multifaceted roles of Bcl11b in thymic and peripheral T cells: impact on immune diseases

The transcription factor Bcl11b is expressed in all T cell subsets and progenitors, starting from the DN2 stage of T cell development, and it regulates critical processes implicated in the development, function, and survival of many of these cells. Among the common roles of Bcl11b in T cell progenitors and mature T cell subsets are the repression of the innate genetic program and, to some extent, expression maintenance of TCR-signaling components. However, Bcl11b also has unique roles in specific T cell populations, suggesting that its functions depend on cell type and activation state of the cell. In this article, we provide a comprehensive review of the roles of Bcl11b in progenitors, effector T cells, regulatory T cells, and invariant NKT cells, as well as its impact on immune diseases. While emphasizing common themes, including some that might be extended to skin and neurons, we also describe the control of specific functions in different T cell subsets.