Role of MicroRNA-26b in Glioma Development and Its Mediated Regulation on EphA2

BACKGROUND: MicroRNAs (miRNAs) are short, non-coding RNAs that regulate the expression of multiple target genes. Deregulation of miRNAs is common in human tumorigenesis. Low level expression of miR-26b has been found in glioma cells. However, its underlying mechanism of action has not been determined. METHODOLOGY/PRINCIPAL FINDINGS: Real-time PCR was employed to measure the expression level of miR-26b in glioma patients and cells. The level of miR-26b was inversely correlated with the grade of glioma. Ectopic expression of miR-26b inhibited the proliferation, migration and invasion of human glioma cells. A binding site for miR-26b was identified in the 3'UTR of EphA2. Over-expression of miR-26b in glioma cells repressed the endogenous level of EphA2 protein. Vasculogenic mimicry (VM) experiments were performed to further confirm the effects of miR-26b on the regulation of EphA2, and the results showed that miR-26b inhibited the VM processes which regulated by EphA2. SIGNIFICANCE: This study demonstrated that miR-26b may act as a tumor suppressor in glioma and it directly regulates EphA2 expression. EphA2 is a direct target of miR-26b, and the down-regulation of EphA2 mediated by miR-26b is dependent on the binding of miR-26b to a specific response element of microRNA in the 3'UTR region of EphA2 mRNA

Hypoxia-Regulated miR-146a Targets Cell Adhesion Molecule 2 to Promote Proliferation, Migration, and Invasion of Clear Cell Renal Cell Carcinoma

Background/Aims: miR-146a has recently been shown to promote cell proliferation, migration, and invasion in many cancers, but the role of miR-146a in clear cell renal cell carcinoma (ccRCC) remains unclear. Methods: Reverse transcription quantitative PCR (RT-qPCR) was performed to investigate the mRNA expression of miR-146a and CADM2 in ccRCC tissues. The luciferase reporter assay, Western blotting, and ChIP assay were carried out to explore the promoter and the transcription factor of miR-146a. Moreover, the effect of miR-146a and CADM2 on ccRCC cells was explored using methyl thiazolyl tetrazolium, colony formation, and migration and invasion assays. The luciferase reporter assay, RT-qPCR, western blotting, and immunofluorescence assay were carried out to investigate whether CADM2 is directly regulated by miR-146a. A tumor xenograft model and immunohistochemical staining were used to examine the carcinogenic effect of miR-146a and CADM2 in vivo. Results: miR-146a has been shown to promote cell proliferation, migration, and invasion. Here, we found that miR-146a is highly expressed in ccRCC tissues, whereas CADM2 is down-regulated. Hypoxia can induce the expression of miR-146a by stimulating its promoter. In addition, we demonstrated that miR-146a promoted and CADM2 inhibited proliferation, migration, and invasion of ccRCC cells. The 3’ untranslated region (UTR) luciferase reporter assay identified that miR-146a targeted the 3’ UTR of CADM2 and negatively regulated its expression. Ectopic expression of CADM2 counteracted the promoting effect of miR-146a on cell proliferation, migration, invasion, and the epithelial–mesenchymal transition process. Conclusion: Together, the finding of down-regulation of CADM2 by miR-146a can provide new insights into ccRCC pathogenesis and might contribute to the development of novel therapeutic strategies

Four novel variants identified in primary hyperoxaluria and genotypic and phenotypic analysis in 21 Chinese patients

Background: Primary hyperoxaluria (PH) is a rare genetic disorder characterized by excessive accumulation of oxalate in plasma and urine, resulting in various phenotypes due to allelic and clinical heterogeneity. This study aimed to analyze the genotype of 21 Chinese patients with primary hyperoxaluria (PH) and explore their correlations between genotype and phenotype.Methods: Combined with clinical phenotypic and genetic analysis, we identified 21 PH patients from highly suspected Chinese patients. The clinical, biochemical, and genetic data of the 21 patients were subsequently reviewed.Results: We reported 21 cases of PH in China, including 12 cases of PH1, 3 cases of PH2 and 6 cases of PH3, and identified 2 novel variants (c.632T > G and c.823_824del) in AGXT gene and 2 novel variants (c.258_272del and c.866-34_866-8del) in GRHPR gene, respectively. A possible PH3 hotspot variant c.769T > G was identified for the first time. In addition, patients with PH1 showed higher levels of creatinine and lower eGFR than those with PH2 and PH3. In PH1, patients with severe variants in both alleles had significantly higher creatinine and lower eGFR than other patients. Delayed diagnosis still existed in some late-onset patients. Of all cases, 6 had reached to end-stage kidney disease (ESKD) at diagnosis with systemic oxalosis. Five patients were on dialysis and three had undergone kidney or liver transplants. Notably, four patients showed a favorable therapeutic response to vitamin B6, and c.823_824dup and c.145A > C may be identified as potentially vitamin B6-sensitive genotypes.Conclusion: In brief, our study identified 4 novel variants and extended the variant spectrum of PH in the Chinese population. The clinical phenotype was characterized by large heterogeneity, which may be determined by genotype and a variety of other factors. We first reported two variants that may be sensitive to vitamin B6 therapy in Chinese population, providing valuable references for clinical treatment. In addition, early screening and prognosis of PH should be given more attention. We propose to establish a large-scale registration system for rare genetic diseases in China and call for more attention on rare kidney genetic diseases

OP9-Lhx2 stromal cells facilitate derivation of hematopoietic progenitors both in vitro and in vivo

AbstractGenerating engraftable hematopoietic stem cells (HSCs) from pluripotent stem cells (PSCs) is an ideal approach for obtaining induced HSCs for cell therapy. However, the path from PSCs to robustly induced HSCs (iHSCs) in vitro remains elusive. We hypothesize that the modification of hematopoietic niche cells by transcription factors facilitates the derivation of induced HSCs from PSCs. The Lhx2 transcription factor is expressed in fetal liver stromal cells but not in fetal blood cells. Knocking out Lhx2 leads to a fetal hematopoietic defect in a cell non-autonomous role. In this study, we demonstrate that the ectopic expression of Lhx2 in OP9 cells (OP9-Lhx2) accelerates the hematopoietic differentiation of PSCs. OP9-Lhx2 significantly increased the yields of hematopoietic progenitor cells via co-culture with PSCs in vitro. Interestingly, the co-injection of OP9-Lhx2 and PSCs into immune deficient mice also increased the proportion of hematopoietic progenitors via the formation of teratomas. The transplantation of phenotypic HSCs from OP9-Lhx2 teratomas but not from the OP9 control supported a transient repopulating capability. The upregulation of Apln gene by Lhx2 is correlated to the hematopoietic commitment property of OP9-Lhx2. Furthermore, the enforced expression of Apln in OP9 cells significantly increased the hematopoietic differentiation of PSCs. These results indicate that OP9-Lhx2 is a good cell line for regeneration of hematopoietic progenitors both in vitro and in vivo

Genetic Diversity and Symbiotic Efficiency of Nodulating Rhizobia Isolated from Root Nodules of Faba Bean in One Field

Thirty-one nodulating rhizobium strains were collected from root nodules of spring and winter type faba bean cultivars grown in micro ecoarea, i.e. the same field in Chengdu plain, China. The symbiotic efficiency and phylogeny of these strains were studied. Effectively nitrogen fixing strains were isolated from both winter type and spring type cultivars. Based on phylogenetic analysis of 16S rRNA gene and concatenated sequence of atpD, glnII and recA genes, the isolates were assigned as Rhizobium anhuiense and a potential new Rhizobium species. The isolates were diverse on symbiosis related gene level, carrying five, four and three variants of nifH, nodC and nodD, respectively. Strains carrying similar gene combinations were trapped by both winter and spring cultivars, disagreeing with the specificity of symbiotic genotypes to reported earlier faba bean ecotypes.Peer reviewe

Atomic structures of Coxsackievirus A6 and its complex with a neutralizing antibody

手足口病是一种由人肠道病毒引起的全球性传染病，主要发生于5岁以下的婴幼儿，严重危害公众健康。根据获得的手足口病流行病学和病原学调查数据，目前认为CVA6与EV71和CVA16一样应作为优先的手足口病疫苗预防对象，亟需研制有效的预防和治疗方法。然而令人遗憾的是，目前对于CVA6的基础病毒学特别是结构生物学知识均缺乏足够了解，严重制约了相关研究的有效开展。 夏宁邵教授团队研究首次揭示了手足口病重要病原体柯萨奇病毒A组6型（CVA6）的病毒颗粒及其与中和抗体复合物的精确三维结构，为新型疫苗和治疗药物的研制提供了重要的理论基础。这项研究发现并精确描绘了CVA6的病毒颗粒及其与优势中和抗体的结构特征，首次完成了对CVA6的高精度“成像”，为新型疫苗和治疗药物研制提供了关键基础。 该研究工作在厦门大学分子疫苗学和分子诊断学国家重点实验室、国家传染病诊断试剂与疫苗工程技术研究中心科研平台完成。夏宁邵教授、颜晓东博士、程通副教授为该研究论文的共同通讯作者。颜晓东博士来自美国加州大学圣地亚哥分校，同时受聘为我校双聘教授。共同第一作者为徐龙发博士生、郑清炳工程师和李少伟教授。【Abstract】Coxsackievirus A6 (CVA6) has recently emerged as a major cause of hand, foot and mouth disease in children worldwide but no vaccine is available against CVA6 infections. Here, we demonstrate the isolation of two forms of stable CVA6 particles-procapsid and A-particle-with excellent biochemical stability and natural antigenicity to serve as vaccine candidates. Despite the presence (in A-particle) or absence (in procapsid) of capsid-RNA interactions, the two CVA6 particles have essentially identical atomic capsid structures resembling the uncoating intermediates of other enteroviruses. Our near-atomic resolution structure of CVA6 A-particle complexed with a neutralizing antibody maps an immune-dominant neutralizing epitope to the surface loops of VP1. The structure-guided cell-based inhibition studies further demonstrate that these loops could serve as excellent targets for designing anti-CVA6 vaccines.This work was supported by a grant from the National Natural Science Foundation of China (No. 31670933 and 81401669), the National Science and Technology Major Projects for Major New Drugs Innovation and Development (No. 2017ZX09101005-005-003), the National Science and Technology Major Project of Infectious Diseases (No. 2017ZX10304402-002-003) and the Natural Science Foundation of Fujian Province (No. 2015J05073). This work was also supported in part by funding to T.S.B. from the National Institutes of Health (Grant R37-GM33050). 研究工作也得到了国际病毒结构生物学权威专家美国加州大学洛杉矶分校周正洪教授的大力支持和帮助，获得了国家自然科学基金、新药创制国家科技重大专项、传染病防治国家科技重大专项和福建省自然科学基金的资助

Uncoupled Embryonic and Extra-Embryonic Tissues Compromise Blastocyst Development after Somatic Cell Nuclear Transfer

Somatic cell nuclear transfer (SCNT) is the most efficient cell reprogramming technique available, especially when working with bovine species. Although SCNT blastocysts performed equally well or better than controls in the weeks following embryo transfer at Day 7, elongation and gastrulation defects were observed prior to implantation. To understand the developmental implications of embryonic/extra-embryonic interactions, the morphological and molecular features of elongating and gastrulating tissues were analysed. At Day 18, 30 SCNT conceptuses were compared to 20 controls (AI and IVP: 10 conceptuses each); one-half of the SCNT conceptuses appeared normal while the other half showed signs of atypical elongation and gastrulation. SCNT was also associated with a high incidence of discordance in embryonic and extra-embryonic patterns, as evidenced by morphological and molecular “uncoupling”. Elongation appeared to be secondarily affected; only 3 of 30 conceptuses had abnormally elongated shapes and there were very few differences in gene expression when they were compared to the controls. However, some of these differences could be linked to defects in microvilli formation or extracellular matrix composition and could thus impact extra-embryonic functions. In contrast to elongation, gastrulation stages included embryonic defects that likely affected the hypoblast, the epiblast, or the early stages of their differentiation. When taking into account SCNT conceptus somatic origin, i.e. the reprogramming efficiency of each bovine ear fibroblast (Low: 0029, Med: 7711, High: 5538), we found that embryonic abnormalities or severe embryonic/extra-embryonic uncoupling were more tightly correlated to embryo loss at implantation than were elongation defects. Alternatively, extra-embryonic differences between SCNT and control conceptuses at Day 18 were related to molecular plasticity (high efficiency/high plasticity) and subsequent pregnancy loss. Finally, because it alters re-differentiation processes in vivo, SCNT reprogramming highlights temporally and spatially restricted interactions among cells and tissues in a unique way

Two-Step Pricing Decision Models for Manufacturer-Led Dual-Channel Supply Chains

In this paper, we study the optimal profit change in a manufacturer-led dual-channel supply chain under centralized decision-making and decentralized decision-making scenarios. The supply chain is composed of only a single supplier, a manufacturer, and a retailer, and the manufacturer plays a leading role in the supply chain. Meanwhile, the following conditions exist simultaneously: the promotion levels of retailers in offline physical stores, the promotion compensation given by manufacturers to retailers, and channel competition. In order to coordinate the profits of channel members, a two-step pricing decision model is established. This research shows that using a two-step pricing decision model can make the retailer’s optimal promotion fees and the manufacturer’s optimal sales compensation fees the same as the centralized decision-making’s optimal values; however, the results are not good, because after the coordination, the retailer’s profits increase and the manufacturer’s profits decrease, and, as a consequence, the retailer needs to pay a fixed fee to the manufacturer within the validity of the contract, which is signed by both sides, to achieve a win–win situation for the channel members