The effectual clinical benefits of immune checkpoint inhibitor (ICI) are hampered by a high rate of innate resistance, and VEGFA may contribute to ICI treatment resistance. In this study, we ...endeavored to assess the tumor microenvironment (TME) in VEGFA-overexpressed human tumors and mouse tumor models, and to explore whether anti-angiogenesis therapy can overcome the innate resistance to ICI in hyperangiogenesis mouse tumor models and the underlying mechanism. Effect of VEGFA on clinical prognosis and TME was analyzed using TCGA data. The VEGFA-overexpressed mouse breast and colon subcutaneous models were established. PD-1 mAb or apatinib alone and combination therapy were used. Immunohistochemistry and immunofluorescence were used to assess angiogenesis and hypoxia. Flow cytometry, RNA sequencing and MCP-counter were applied to detect tumor immunomicroenvironment. High level of VEGFA mRNA in human tumors is related to poor prognosis and hypoxic, angiogenic and immunosuppressive TME. Upregulation of VEGFA increased the degree of malignancy of tumor cells in vitro and in vivo. VEGFA-overexpressed models were characterized by hypoxic, hyperangiogenic and immunosuppressive TME and indicated innate resistance to ICI. In tumor-bearing mice without VEGFA overexpression, the combination therapy had no synergistic anti-tumor effect compared to monotherapy. However, apatinib alleviated hyperangiogenesis and hypoxia in TME and converted the immunosuppressive TME into an immunostimulatory one in VEGFA-overexpressed tumors. Thus, anti-angiogenesis therapy could improve the efficiency of ICI in VEGFA-overexpressed tumors. Revealing whether there is hypervascularization in tumor tissues may help to clarify the adoption of anti-angiogenesis and ICI combination therapy or ICI monotherapy in cancer treatment.
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EMUNI, FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Intestinal epithelial stem cell identity and location have been the subject of substantial research. Cells in the +4 niche are slow-cycling and label-retaining, whereas a different stem cell niche ...located at the crypt base is occupied by crypt base columnar (CBC) cells. CBCs are distinct from +4 cells, and the relationship between them is unknown, though both give rise to all intestinal epithelial lineages. We demonstrate that Hopx, an atypical homeobox protein, is a specific marker of +4 cells. Hopx-expressing cells give rise to CBCs and all mature intestinal epithelial lineages. Conversely, CBCs can give rise to +4 Hopx-positive cells. These findings demonstrate a bidirectional lineage relationship between active and quiescent stem cells in their niches.
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A thin film consisting of highly ordered and vertically oriented silica mesochannels (SMCs) was prepared on the indium tin oxide (ITO) coated glass electrode surface by chronopotentiometry. The ...mesochannel has a uniform pore size of 2-3 nm in diameter and a positively charged surface due to grafted ammonium groups. The electrostatic and steric effects resulted from control of the surface charge and the ionic buffer concentration make the SMCs permselective, favoring the mass transport of oppositely charged species and repelling that of similarly charged ones. By using differential pulse voltammetry (DPV), the SMCs with this charge selectivity can be employed for permselective detection of ascorbic acid (AA) and dopamine (DA) that are oppositely charged compounds. The obtained linear detection range was 49-2651 μM for AA and 20-226 μM for DA, respectively. AA and DA in real samples were also determined by the SMC film modified electrode.
Objective
To compare endometrial receptivity in patients with and without unexplained recurrent implantation failure (URIF) and the benefits of low‐dose aspirin treatment in women with URIF.
Methods
...A retrospective study was conducted at Ren Ji Hospital, Shanghai, from January 2014 to January 2017. Endometrial thickness, pulsatility index (PI), resistive index (RI), and systolic‐to‐diastolic ratio (S/D) values of endometrial and uterine perfusion were recorded and compared between women with and without URIF. Receiver operating characteristic (ROC) curve analysis was used to evaluate the predictive accuracy of the risk of URIF. Ultrasonography examination was repeated after 2 months of treatment with low‐dose aspirin.
Results
PI, RI, and S/D values for endometrial blood flow were significantly higher in URIF patients than the control group (P < 0.001). The predictive indexes were 0.833, 0.857, and 0.839, respectively. Differences between the groups for endometrial thickness and impedance of uterine perfusion were not significant (P > 0.05). After low‐dose aspirin treatment, endometrial and uterine arterial blood flow resistance in URIF patients was significantly lower than before treatment (P < 0.05).
Conclusion
URIF patients had inappropriate endometrial blood flow. Doppler parameters are promising for predicting women at high risk of URIF. Low‐dose aspirin treatment can improve endometrial receptivity.
Doppler parameters are promising for predicting women at high risk of unexplained recurrent implantation failure. Low‐dose aspirin treatment can improve endometrial receptivity.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The plasticity of differentiated cells in adult tissues undergoing repair is an area of intense research. Pulmonary alveolar type II cells produce surfactant and function as progenitors in the adult, ...demonstrating both self-renewal and differentiation into gas exchanging type I cells. In vivo, type I cells are thought to be terminally differentiated and their ability to give rise to alternate lineages has not been reported. Here we show that Hopx becomes restricted to type I cells during development. However, unexpectedly, lineage-labelled Hopx(+) cells both proliferate and generate type II cells during adult alveolar regrowth following partial pneumonectomy. In clonal 3D culture, single Hopx(+) type I cells generate organoids composed of type I and type II cells, a process modulated by TGFβ signalling. These findings demonstrate unanticipated plasticity of type I cells and a bidirectional lineage relationship between distinct differentiated alveolar epithelial cell types in vivo and in single-cell culture.
During the stepwise specification and differentiation of tissue-specific multipotent progenitors, lineage-specific transcriptional networks are activated or repressed to orchestrate cell ...specification. The gas-exchange niche in the lung contains two major epithelial cell types, alveolar type 1 (AT1) and AT2 cells, and the timing of lineage specification of these cells is critical for the correct formation of this niche and postnatal survival. Integrating cell-specific lineage tracing studies, spatially specific mRNA transcript and protein expression, and single-cell RNA-sequencing analysis, we demonstrate that specification of alveolar epithelial cell fate begins concomitantly with the proximal–distal specification of epithelial progenitors and branching morphogenesis earlier than previously appreciated. By using a newly developed dual-lineage tracing system, we show that bipotent alveolar cells that give rise to AT1 and AT2 cells are a minor contributor to the alveolar epithelial population. Furthermore, single-cell assessment of the transcriptome identifies specified AT1 and AT2 progenitors rather than bipotent cells during sacculation. These data reveal a paradigm of organ formation whereby lineage specification occurs during the nascent stages of development coincident with broad tissue-patterning processes, including axial patterning of the endoderm and branching morphogenesis.
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This study aimed to evaluate the role of the clinical pharmacist in the rational use of proton pump inhibitors (PPIs) in a general surgery department. All enrolled patients had attended the general ...surgery department of a tertiary hospital. This single-center prospective study compared differences in the overall rate of rational PPI use, proportion of unindicated PPI use, utilization rate, average defined daily dose (DDD), drug costs, PPI costs, and cost-effectiveness of clinical pharmacist intervention between the intervention (538 cases) and control (536 cases) groups. In the intervention group, Pareto and fishbone diagram analyses were combined with the Plan-Do-Check-Act cycle; Statistical Package for the Social Sciences was used for analyzing all data. The overall rate of rational PPI use was significantly higher in the intervention group than in the control group (
< 0.01). The proportion of unindicated PPI use, utilization rate, average DDD, drug costs, and PPI costs were significantly lower in the intervention group than in the control group (
< 0.05). Cost-effectiveness analysis for the overall rate of rational PPI use indicated a positive impact of intervention, with economic benefits in the intervention group. Clinical pharmacist intervention for rational use of PPIs in general surgery departments could significantly increase the overall rate of rational PPI use; it could also reduce the proportion of unindicated PPI use, utilization rates, average DDDs, drug costs, and PPIs costs. Pharmacist intervention also offers economic benefits by improving the overall rate of rational PPI use.
Exosomes released from decidual stromal cells (DSC-exos) play a crucial role in facilitating the epithelial-mesenchymal transition (EMT) of trophoblasts and insufficient trophoblasts EMT are ...associated with URSA (unexplained recurrent spontaneous abortion). However, the mechanisms underlying DSC-exos inducing EMT is not completely understood.
DSC-exos of normal pregnant women (N-DSC-exos) and URSA patients (URSA-DSC-exos) were extracted and characterized. Characterization of the isolated DSC-exos was performed using with TEM (transmission electron microscopy), NTA (nanoparticle tracking analysis), and WB (western blot) techniques. Subsequently, these DSC-exos were co-cultured with trophoblasts cell lines (HTR-8/SVneo). The influence of both N-DSC-exos and URSA-DSC-exos on trophoblasts proliferation, invasion and migration, as well as on the expression of EMT-related proteins, was evaluated through a series of assays including CCK8 assays, wound healing assays, transwell assays, and western blot, respectively. Then rescue experiments were performed by β-TrCP knockdown or β-TrCP overexpressing trophoblasts with snail-siRNA transfection or β-TrCP overexpressing Lentivirus infection, respectively. Finally, animal experiments were employed to explore the effect of N-DSC-exos on embryo absorption in mice.
We found increased β-TrCP expression in the villus of URSA patients when compared to the normal pregnant women, alongside reduction in the levels of both snail and N-cadherin within URSA patients. N-DSC-exos can promote the EMT of the trophoblast by inhibiting β-TrCP-mediated ubiquitination and degradation of transcription factor snail. Moreover the capacity to promote EMT was found to be more potent in N-DSC-exos than URSA-DSC-exos. Down-regulation of snail or overexpression of β-TrCP can reverse the effects of N-DSC-exos on trophoblast. Finally, in vivo experiment suggested that N-DSC-exos significantly reduced the embryo resorption rate of spontaneous abortion mouse model.
Our findings indicate that URSA-DSC-exos caused insufficient migration and invasion of trophoblast because of disturbing of β-TrCP-mediated ubiquitination and degradation of EMT transcription factor snail. Elucidating the underlying mechanism of this dysregulation may shed light on the novel pathways through which DSC-exos influence trophoblast function, thereby contributing to our understanding of their role in URSA.
Pathogenic mutations in LAMIN A/C (LMNA) cause abnormal nuclear structure and laminopathies. These diseases have myriad tissue-specific phenotypes, including dilated cardiomyopathy (DCM), but how ...LMNA mutations result in tissue-restricted disease phenotypes remains unclear. We introduced LMNA mutations from individuals with DCM into human induced pluripotent stem cells (hiPSCs) and found that hiPSC-derived cardiomyocytes, in contrast to hepatocytes or adipocytes, exhibit aberrant nuclear morphology and specific disruptions in peripheral chromatin. Disrupted regions were enriched for transcriptionally active genes and regions with lower LAMIN B1 contact frequency. The lamina-chromatin interactions disrupted in mutant cardiomyocytes were enriched for genes associated with non-myocyte lineages and correlated with higher expression of those genes. Myocardium from individuals with LMNA variants similarly showed aberrant expression of non-myocyte pathways. We propose that the lamina network safeguards cellular identity and that pathogenic LMNA variants disrupt peripheral chromatin with specific epigenetic and molecular characteristics, causing misexpression of genes normally expressed in other cell types.
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•Pathogenic LMNA variants disrupt peripheral chromatin in a cell-type-specific manner•Loss of lamina-bound chromatin occurs in regions with specific characteristics•Peripheral chromatin organization maintains silencing of alternative fate genes
Shah et al. demonstrate that pathogenic LMNA variants affect peripheral chromatin organization in a cell-type-specific manner. Their data suggest that lamina-chromatin interactions guard cellular identity. Pathogenic LMNA variants disrupt peripheral chromatin organization and abrogate normal silencing of alternative fate genes in cardiomyocytes.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Making cardiomyocytes
In the heart, multiple cell types work together. Cardiac progenitor cells give rise to cardiomyocyte, endothelial, or smooth muscle lineages. However, the identity of a marker ...specific to cardiomyocyte formation has been elusive. Jain
et al.
now identify a specialized progenitor population that is committed exclusively to forming cardiomyocytes. They also identify the niche signals that promote lineage commitment and the mechanisms involved in making cardiomyocytes. The findings may help in the development of future cell-based regenerative therapeutics for heart disease.
Science
, this issue
10.1126/science.aaa6071
Identification of the committed cardiomyoblast that retains proliferative potential may inform cardiac regenerative therapeutics.
INTRODUCTION
Cardiac progenitor cells are multipotent, and lineage analyses of murine and chick cardiac development have demonstrated that these cells give rise to the cardiac endothelium, smooth muscle, and cardiomyocytes. However, the mechanisms governing commitment to the myocyte lineage in vivo remain largely unknown. Further understanding of these mechanisms, and of the identity of progenitors committed to the myocyte lineage, may advance cardiac regenerative therapies.
RATIONALE
Hopx is an atypical homeodomain expressed in cardiac mesoderm shortly after cardiac progenitor cells are first evident. Previous studies have demonstrated that Hopx functions as a nuclear transcription co-repressor and is expressed in adult, +4 intestinal stem cells and hair follicle bulge stem cells. We compare lineage tracing of multipotent cardiac progenitor cells marked by Islet1 and Nkx2-5 expression with lineage tracing of Hopx
+
cells. We also perform functional studies of Hopx from endogenous tissue and differentiated embryoid bodies to identify mechanisms promoting commitment and myogenesis.
RESULTS
We define and characterize a Hopx-expressing cardiomyoblast intermediate that is committed to the cardiomyocyte fate. Hopx
+
is initially expressed in a subset of cardiac progenitor cells residing in the precardiac mesoderm prior to the expression of troponin T, a component of the contractile sarcomere apparatus of myocytes. Lineage-tracing experiments demonstrate that Hopx
+
cells give rise to cardiac myocytes exclusively. Early Hopx
+
cardiomyoblasts expand during cardiogenesis.
Overexpression of Hopx in cardiac progenitor cells leads to an increase in myocytes, whereas Hopx deficiency compromises myogenesis. Whole-genome analysis reveals that Hopx occupies regulatory regions of multiple Wnt-related genes, and
Hopx
–/–
cardiac tissues are characterized by an expansion of Wnt signaling. Restoration of Wnt levels during differentiation of
Hopx
–/–
embryoid bodies partially rescues myogenesis. Wnt signaling is a potent regulator of stemness of cardiac progenitor cells, and our data suggest that Hopx promotes myogenesis by repressing Wnt signaling.
Cardiac progenitor cells down-regulate Wnt signaling as they enter the cardiac outflow tract, coincident with the expression of Hopx. The outflow tract is also enriched for bone morphogenetic protein (Bmp) signaling, known to influence differentiation of myocytes. Hopx physically interacts with activated Smad complexes in vitro and in vivo. Exogenous Bmp4 represses Wnt signaling in cardiac explants, and Bmp4-mediated Wnt repression requires Hopx. Thus, Hopx functions to couple Bmp signaling to repression of Wnt.
CONCLUSION
Our work defines an intermediate cardiac progenitor that expresses Hopx and is committed exclusively to the myocyte fate. Therefore, akin to an erythroblast in hematopoietic differentiation, we have termed these committed cardiac progenitor cells “cardiomyoblasts.” The ability to identify committed, but undifferentiated, cardiomyocyte precursors may facilitate development of cardiac regenerative therapies, including those using embryonic stem cells and induced pluripotent stem cells.
Hopx functions to promote myogenesis by physically interacting with Smad proteins to repress Wnt signaling. Our findings raise the possibility that Hopx-mediated integration of Bmp signaling to repress Wnt may be active in other progenitor populations and may potentially underlie the tumor suppressor function of Hopx.
Lineage tracing of Hopx
+
cells.
Images depicting lineage tracing of early Hopx
+
cardiomyoblasts that give rise to myocytes in the left ventricle and atria. Some images are duplicated and pseudocolored.
Cardiac progenitor cells are multipotent and give rise to cardiac endothelium, smooth muscle, and cardiomyocytes. Here, we define and characterize the cardiomyoblast intermediate that is committed to the cardiomyocyte fate, and we characterize the niche signals that regulate commitment. Cardiomyoblasts express Hopx, which functions to coordinate local Bmp signals to inhibit the Wnt pathway, thus promoting cardiomyogenesis. Hopx integrates Bmp and Wnt signaling by physically interacting with activated Smads and repressing Wnt genes. The identification of the committed cardiomyoblast that retains proliferative potential will inform cardiac regenerative therapeutics. In addition, Bmp signals characterize adult stem cell niches in other tissues where Hopx-mediated inhibition of Wnt is likely to contribute to stem cell quiescence and to explain the role of Hopx as a tumor suppressor.
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