Targeting EphA2 with miR-124 mediates Erlotinib resistance in K-RAS mutated pancreatic cancer

OBJECTIVES

Chemotheraputic drug resistance is a critical factor associated with the poor survival in advanced/metastatic pancreatic cancer (PC) patients.

METHODS

Human pancreatic cell lines Capan-1 and BXPC-3 were cultured with different concentrations of erlotinib (0, 10, 50, and 100 μm) for 48 h. The relative cell viability and apoptosis was detected using MTT assays and flow cytometry apoptosis analysis, respectively. Transfection of pcDNA-EphA2, si-EphA2 and miR-124 mimic/inhibitor was used to modulate the intracellular level of EphA2 and miR-124. The interaction between miR-124 and the 3'UTR of EphA2 was explored using dual luciferase reporter assay.

KEY FINDINGS

Compared with BXPC-3 cells, Capan-1 cells showed resistance to differential concentration treatment of erlotinib. The expression of EphA-2 was significantly increased and the expression of miR-124 was significantly decreased in Capan-1 cells. Overexpressing EphA2 induced resistance of BXPC-3 cells to erlotinib treatment. And EphA2 was identified as a novel target gene for miR-124. MiR-124 overexpression was able to sensitize the response of Capan-1 cells to erlotinib through inhibiting EphA2. Furthermore, both miR-124 overexpression and EphA2 inhibition sensitized Capan-1 cells to erlotinib in xenograft model.

CONCLUSIONS

Our study demonstrated that EphA2 rescued by miR-124 downregulation conferred the erlotinib resistance of PC cell Capan-1 with K-RAS mutation.

Clinical analysis of 17 cases of neonatal osteomyelitis: A retrospective study

Although acute osteomyelitis is rare in neonates, it might result in severe sequelae such as joint destruction and growth failure if it is not diagnosed and treated early. However, few studies have focused on the clinical features and treatment of this disease.A retrospective review of 17 cases of neonatal osteomyelitis, for which the patients underwent medical treatment alone or combined with surgery at the Children's Hospital of Zhejiang University School of Medicine between January 2009 and September 2016, was conducted. Medical treatment included the use of antibiotics and supportive care. Surgery was performed in cases with subperiosteal abscess (>1 cm) or clinical deterioration despite antibiotic therapy.All of the patients (11 men and 6 women) were term neonates. The main complaints were redness or swelling around the affected bone and fever. The most common sites were the femur (29.4%) and humerus (23.5%). There were 14 (82.35%) cases with positive cultures: Staphylococcus accounted for 71.43% (n = 10), followed by Salmonella (n = 1), Streptococcus pneumoniae (n = 1), Klebsiella pneumoniae (n = 1), and Escherichia coli (n = 1). X-rays (n = 14), ultrasound (n = 6), computed tomography (CT) (n = 5), or magnetic resonance imaging (MRI) (n = 7) were performed. Three of 14 x-rays were not pathological at the onset of the disease, while the positive rate of MRI in detecting osteomyelitis was 100%. Eleven of 17 cases underwent surgical drainage, and higher white blood cell (WBC) counts were found in patients requiring surgery (P < .05). The prognosis for all patients was good without severe sequelae with a mean follow-up period of 49.47 ± 23.43 months.In conclusion, the prognosis of neonatal osteomyelitis with early active treatment is good. MRI is advocated for detecting early osteomyelitis. Additionally, neonates with higher WBC count together with osteomyelitis have an increased risk for surgery.

A Polysaccharide Extract from Maitake Culinary-Medicinal Mushroom, Grifola frondosa (Agaricomycetes) Ameliorates Learning and Memory Function in Aluminum Chloride-Induced Amnesia in Mice

Maitake (Grifola frondosa) is an edible mushroom exhibiting high nutritional value in terms of containing health-beneficial bioactive compounds. Previously, we reported that a protein-bound polysaccharide bioactive component of G. frondosa (PGM) could enhance the expression of α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor (AMPAR), which is critical for learning and memory. However, the potential benefits of PGM on learning and memory function have never been investigated. In the current study, we aimed to explore the beneficial effect of PGM on learning and memory function in aluminum chloride (AlCl3)-induced amnesia in mice and to explore the underlying mechanisms. Mice were intraperitoneally administered with AlCl3 (60 mg/kg/d) and PGM (5, 10, or 20 mg/kg/d) for 6 weeks consecutively, and then the Morris water maze (MWM) test was conducted to assess the learning and memory function. Hematoxylin-eosin staining was performed to observe the morphology of neurons in the hippocampal dentate gyrus (DG). The expression of p-Tau (Ser396), Tau, p-GluA1 (S845), GluA1, and brain-derived neurotrophic factor (BDNF) proteins was evaluated with western blot. We found that PGM (5 and 10 mg/kg/d) significantly improved learning and memory function and attenuated histopathological abnormalities in the hippocampal DG region in the AlCl3-treated mice. Furthermore, PGM treatment significantly enhanced the level of AMPAR and BDNF in the hippocampus, while suppressing the tau protein hyperphosphorylation at the Ser396 site. These findings indicated that PGM could significantly attenuate the AlCl3-induced amnesia through the synergistic action of its active component on tau pathology, AMPAR and BDNF signaling pathway.

Correction: In situ synthesis of a silicon flake/nitrogen-doped graphene-like carbon composite from organoclay for high-performance lithium-ion battery anodes

Correction for ‘In situ synthesis of a silicon flake/nitrogen-doped graphene-like carbon composite from organoclay for high-performance lithium-ion battery anodes’ by Qingze Chen et al., Chem. Commun., 2019, 55, 2644–2647.

Immobilization of enzymes on an organic–inorganic hybrid network consisting of Dawson-type polyoxotungstate and a zinc(ii)-biimidazole complex moiety

A new polyoxometalate (POM)-based organic–inorganic hybrid compound {[(Zn(H₂biim)₂)₃(P₂W₁₈O₆₂)]·6H₂O}_n (1) shows excellent enzyme-loading capability for horseradish peroxidase (HRP) and can be used as a new catalyst for trace H₂O₂ detection in solution.

C5aR1 regulates T follicular helper differentiation and chronic graft-versus-host disease bronchiolitis obliterans

CD4+ follicular helper T (Tfh) cells are specialized providers of T cell help to B cells and can function as pathogenic mediators of murine antibody-dependent chronic graft-versus-host disease (GvHD). Using a parent→F1 model of lupus-like chronic GvHD, in which Tfh cell and germinal center (GC) B cell differentiation occurs over 14 days, we demonstrate that absence of CD4+ T cell-expressed C5a receptor 1 (C5ar1) or pharmacological C5aR1 blockade abrogated generation/expansion of Tfh cells, GC B cells, and autoantibodies. In a Tfh cell-dependent model of chronic GvHD manifested by bronchiolitis obliterans syndrome (BOS), C5aR1 antagonism initiated in mice with established disease ameliorated BOS and abolished the associated differentiation of Tfh and GC B cells. Guided by RNA-sequencing data, mechanistic studies performed using murine and human T cells showed that C5aR1 signaling amplifies IL-6-dependent expression of the transcription factor c-MAF and the cytokine IL-21 via phosphorylating phosphokinase B (AKT) and activating the mammalian target of rapamycin (mTOR). In addition to linking C5aR1-initiated signaling to Tfh cell differentiation, our findings suggest that C5aR1 may be a useful therapeutic target for prevention and/or treatment of individuals with Tfh cell-dependent diseases, including those chronic GvHD patients who have anti-host reactive antibodies.

Association of Vitamin D Receptor Gene TaqI, BsmI, FokI, and ApaI Polymorphisms and Susceptibility to Hallux Valgus in the Chinese Population

Previous studies have indicated that vitamin D receptor (VDR) TaqI, BsmI, FokI and ApaI gene polymorphisms are associated with the risk of skeletal malformations with inflammation. However, the potential association of VDR gene polymorphisms with the susceptibility to hallux valgus remains unclear. To clarify this association, we compared the genotypes of 228 patients with hallux valgus with those of 200 controls using the Multiplex SNaPshot system. The χ² test was used to compare the allele and genotype frequencies between groups, and p ≤ .05 was considered statistically significant. The frequencies of the mutant allele C in TaqI (p= .036; odds ratio [OR] 1.57; 95% confidence interval [CI] 1.03-2.39) and mutant allele A in BsmI (p= .036; OR 1.33; 95% CI 1.02-1.74) were significantly greater in the patients than in the controls. In addition, after adjusting for sex and age, TaqI (p= .047; OR 1.61; 95% CI 1.00-2.58) and BsmI (p= .025; OR 1.67; 95% CI 1.06-2.61) were associated with the risk of hallux valgus through a dominant genetic model. A homozygous genetic model of BsmI was also significantly associated with the risk of hallux valgus (p= .033; OR 1.81; 95% CI 1.05-2.57). However, neither ApaI nor FokI were associated with increased susceptibility. To the best of our knowledge, we have reported for the first time that VDR gene TaqI and BsmI polymorphisms might contribute to the increased risk of hallux valgus in Chinese population.

An Ultrasensitive Calcium Reporter System via CRISPR-Cas9-Mediated Genome Editing in Human Pluripotent Stem Cells

Genetically encoded calcium indicator (GCaMP) proteins have been reported for imaging cardiac cell activity based on intracellular calcium transients. To bring human pluripotent stem cell (hPSC)-derived cardiomyocytes (CMs) to the clinic, it is critical to evaluate the functionality of CMs. Here, we show that GCaMP6s-expressing hPSCs can be generated and used for CM characterization. By leveraging CRISPR-Cas9 genome editing tools, we generated a knockin cell line that constitutively expresses GCaMP6s, an ultrasensitive calcium sensor protein. We further showed that this clone maintained pluripotency and cardiac differentiation potential. These knockin hPSC-derived CMs exhibited sensitive fluorescence fluctuation with spontaneous contraction. We then compared the fluorescence signal with mechanical contraction signal. The knockin hPSC-derived CMs also showed sensitive response to isoprenaline treatment in a concentration-dependent manner. Therefore, the GCaMP6s knockin hPSC line provides a non-invasive, sensitive, and economic approach to characterize the functionality of hPSC-derived CMs.

[Relationships between the levels of serum 25-hydroxyvitamin D and interleukin-6 in patients with Takayasu's arteritis]

Objective: The main purpose of this paper is to evaluate the level of serum 25-hydroxyvitamin D (25-OH-D) and clinical significance in patients with Takayasu's Arteritis (TA). Methods: A total of 62 untreated TA patients (TA group) and 60 healthy people (control group) were enrolled. The level of serum 25-OH-D were measured and compared between groups. The correlations of 25-OH-D level with related indicators were analyzed. Results: Lower concentrations of serum 25-OH-D were detected in TA patients compared with healthy subjects[(11.8±4.7) μg/L versus (23.2±8.3) μg/L](P<0.001). In active stage group, the 25-(OH)-D level of TA were significantly lower than that in remission stage group[(10.5±4.3) μg/L vs (13.3±4.9) μg/L](P=0.021). In all patients with TA, serum 25-OH-D correlated negatively with interleukin (IL)-6 (r=-0.296, P=0.023). There was no correlation between serum 25-OH-D level and C-reactive protein , erythrocyte sedimentation rate , National Institutes of Health Score, Indian Takayasu Clinical Activity Score 2010, and anti-tumor necrosis factor (TNF)-alpha antibody. Conclusion: A high prevalence of vitamin D deficiency was observed in patients with TA. The serum 25-OH-D level were negatively correlated with IL-6.

Notch signaling mediated by Delta-like ligands 1 and 4 controls the pathogenesis of chronic GVHD in mice

Chronic graft-versus-host disease (cGVHD) is a major complication of allogeneic hematopoietic cell transplantation (allo-HCT) and remains an area of unmet clinical need with few treatment options available. Notch blockade prevents acute GVHD in multiple mouse models, but the impact of Notch signaling on cGVHD remains unknown. Using genetic and antibody-mediated strategies of Notch inhibition, we investigated the role of Notch signaling in complementary mouse cGVHD models that mimic several aspects of human cGVHD in search of candidate therapeutics. In the B10.D2→BALB/c model of sclerodermatous cGVHD, Delta-like ligand 4 (Dll4)-driven Notch signaling was essential for disease development. Antibody-mediated Dll4 inhibition conferred maximum benefits when pursued early in a preventative fashion, with anti-Dll1 enhancing early protection. Notch-deficient alloantigen-specific T cells showed no early defects in proliferation or helper polarization in vivo but subsequently exhibited markedly decreased cytokine secretion and enhanced accumulation of FoxP3+ regulatory T cells. In the B6→B10.BR major histocompatibility complex-mismatched model with multi-organ system cGVHD and prominent bronchiolitis obliterans (BO), but not skin manifestations, absence of Notch signaling in T cells provided long-lasting disease protection that was replicated by systemic targeting of Dll1, Dll4, or both Notch ligands, even during established disease. Notch inhibition decreased target organ damage and germinal center formation. Moreover, decreased BO-cGVHD was observed upon inactivation of Notch1 and/or Notch2 in T cells. Systemic targeting of Notch2 alone was safe and conferred therapeutic benefits. Altogether, Notch ligands and receptors regulate key pathogenic steps in cGVHD and emerge as novel druggable targets to prevent or treat different forms of cGVHD.

Geographical Distribution of Biomedical Research in the USA and China

We analyze nearly 20 million geocoded PubMed articles with author affiliations. Using K-means clustering for the lower 48 US states and mainland China, we find that the average published paper is within a relatively short distance of a few centroids. These centroids have shifted very little over the past 30 years, and the distribution of distances to these centroids has not changed much either. The overall country centroids have gradually shifted south (about 0.2° for the USA and 1.7° for China), while the longitude has not moved significantly. These findings indicate that there are few large scientific hubs in the USA and China and the typical investigator is within geographical reach of one such hub. This sets the stage to study centralization of biomedical research at national and regional levels across the globe, and over time.

Research on Spinal Lumbar Sacral Degeneration Finite Element Model

Recent research has shown that lumbar disease has become common in China. Since the structure of the lumbar spine is extremely complex, a finite element analysis method was used to perform biomechanical simulation and analysis of stress and strain on the L3–L4 lumbar segment to provide both a scientific and theoretical basis for clinical diagnosis and medical research. The MC volume-rendering 3D reconstruction method was the first step to accurately constructing the finite element model of the L3–L4 lumbar sacral segment, which was simulated prior to the addition of the ligaments, fibrous ring, and other major spinal tissue. The finite element model network was classified and the material properties of the corresponding parts were described. According to the normal model, careful simulation and deformation were performed, in addition to intervertebral disc degeneration in various cases. We have provided a detailed and professional analysis of the biomechanical properties, providing a powerful biomechanical basis for the diagnosis of intervertebral disc bulge and degeneration.

[Predictive value of serum glycosylated hemoglobin for the onset of nonalcoholic fatty liver disease]

Objective: To discuss the affect of glycosylated hemoglobin (HbA1c) level for the onset of nonalcoholic fatty liver disease (NAFLD) in cohort population. Methods: An epidemiological survey of the relationship between HbA1c and NAFLD conducted in 2012 was based at cohort baseline, and three follow-up sessions conducted in 2013, 2014 and 2015. In total 2 811 subjects were included in the study after exclusion of NAFLD patients at baseline and those who lost their lives due to relocation, and death. The Cox proportional hazard model was used to analyze the relationship between glycosylated hemoglobin and other risk factors of NAFLD. Continuous variables were compared using the t-test or the Mann-Whitney test. χ (2)-test was used for the measurement of categorical data. Results: A total of 2 811 subjects with mean age of 59 (58.2±9.8) years old, including 1 664 males and 1 147 females. Age, waist circumference, body mass index, systolic blood pressure, γ-glutamyltransferase and fasting blood glucose level of HbA1c abnormal group were higher than normal group. The incidence of NAFLD in the abnormal HbA1c level group (25.4%) was higher than normal group (14.9 %), and diastolic blood pressure, high-density lipoprotein cholesterol was lower than normal group and the differences were statistically significant. During the three follow-up intervals, there were 440 new cases of NAFLD, consisting 285 males and 155 females with cumulative incidence of 15.7% (440/2 811). Multivariate Cox regression analysis showed that patients with elevated HbA1c had a higher risk of developing NAFLD (HR 1.796; 95% CI 1.335~2.418; P < 0.01), and the increased HbA1c level after adjustment for gender, age, and metabolic syndrome-related factors remained an independent risk factors for NAFLD (HR 1.580; 95.0% CI 1.161-2.152; P < 0.01). Conclusion: An elevated HbA1c levels have a positive predictive value for the onset of NAFLD.

Multivariate analysis of inflammatory endotypes in recurrent nasal polyposis in a Chinese population

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) remains a challenging clinical problem due to its propensity for recurrence. However, data on the frequency of CRSwNP recurrence after surgery in China are rare.

METHODS

78 CRSwNP patients undergoing functional endoscopic sinus surgery were followed-up for 8 years and classified into recurrent and non-recurrent groups. A cluster analysis of the CRSwNP based on inflammatory endotypes was performed, and the endotypes were secondarily matched with clinical phenotypes.

RESULTS

The recurrence rate of CRSwNP in Southwest China was 21.8% over 8 years post-surgery. The CRSwNP was classified into 4 clusters: cluster 1 (higher expression of IL-5, IgE, and ECP and high positivity rate for SE-IgE); cluster 2 (higher concentrations of IL-6, IL-8 and MPO); cluster 3 (higher concentrations of TNF-alpha; and IFN-gamma); and cluster 4 (higher expression of IL-17). Cluster 1 (type-2 inflammation) exhibited the highest recurrence rate, co-morbid asthma and atopy. Notably, the ECP/MPO ratio increased significantly in patients with non-type-2 recurrent CRSwNP 8 years after the first surgery.

CONCLUSION

Different inflammatory endotypes of CRSwNP exhibited clearly different prognoses. The type-2 subgroup had high recurrence and co-morbid asthma rates comparable to the rates reported in Western countries.

LINC00152 promotes the proliferation of gastric cancer cells by regulating B-cell lymphoma-2

LINC00152 has been considered to be associated with the tumorigenesis and the occurrence of gastric cancer; however, the mechanism of LINC00152 has yet to be fully elucidated. In the present study, the expression levels of LINC00152 in tissues, serum, and peripheral blood mononuclear cells (PBMCs) of patients with gastric cancer were determined using real-time polymerase chain reaction. The functions of LINC00152 with respect to the proliferation, apoptosis, migration, and invasive abilities of the gastric cancer cells were evaluated by cell proliferation analysis, flow cytometry, cell scratch wound assay, and transwell migration experiments. A mouse xenotransplant model of gastric tumors was established to detect the role of LINC00152 in vivo, and the expression levels of B-cell lymphoma-2 (Bcl-2) family proteins were investigated by Western blot analysis. The results revealed that LINC00152 was overexpressed in tissues, serum, and PBMCs of patients with gastric cancer. Moreover, LINC00152 could promote the migration and invasive abilities and suppress the apoptosis, of gastric cancer cells through regulating the Bcl-2 protein family. LINC00152 could bind with Bcl-2 directly to induce the activation of cell cycle signaling, and this may be a potential target for the therapy of gastric cancer in the future.