Epigenetic regulation of miR-124 by Hepatitis C Virus core protein promotes migration and invasion of intrahepatic cholangiocarcinoma cells by targeting SMYD3

Hepatitis C Virus core protein (HCVc) plays important roles in the development of intrahepatic cholangiocarcinoma (ICC). MicroRNAs (miRNAs) contribute to tumor progression by interacting with downstream target genes. However, the regulation and role of miRNAs in HCV-related intrahepatic cholangiocarcinoma (HCV-ICC) is poorly understood. In this study, we found that miR-124 was down-regulated in HCV-ICC and the induction of DNMT1 by HCVc mediated the suppression of miR-124. Over-expression of miR-124 suppressed cell migration and invasion in vitro, and reduced the protein levels of SMYD3 and downstream target genes (c-Myc and MMP9). Knockdown of SMYD3 inhibited cell migration and invasion resembling that of miR-124 over-expression. In conclusion, our studies indicate that low miR-124 levels mediated by HCVc via DNMT1 promote ICC cell migration and invasion by targeting SMYD3.     

Hepatitis C virus core upregulates the methylation status of the RASSF1A promoter through regulation of SMYD3 in hilar cholangiocarcinoma cells

Increasing evidence has been accumulated indicating the important role of epigenetic regulation in tumor genesis. Previously, we observed that the transfection of hepatitis C virus core (HCVc) protein led to malignant transformation in normal biliary cells, and that tumor suppressor gene RASSF1A was downregulated in many hilar cholangiocarcinoma patients by hypermethylation in the promoter region. In the present study, we found SET and MYND domain-containing protein 3 (SMYD3), a novel histone methyltransferase, was overexpressed in cholangiocarcinoma patients especially in those with HCV infection. Transfection of HCVc into hilar cholangiocarcinoma cell lines QBC939 and FRH0201 could upregulate the expression of SMYD3 and promote cell growth, which was consistent with the results of our clinical research. This phenomenon indicated that SMYD3 was related to the epigenetic regulation of cholangiocarcinoma genesis with HCV infection. Overexpression of SMYD3 could inhibit RASSF1A expression, whereas inhibition of SMYD3 by siRNA improved its expression. Methylation-specific polymerase chain reaction (MS-PCR) results showed the methylation status of RASSF1A promoter was regulated by SMYD3. In conclusion, HCVc could upregulate the methylation status of the RASSF1A promoter through regulation of SMYD3, and histone methylation may affect the DNA methylation of downstream gene by an unknown mechanism.     

耐碳青霉烯鲍曼不动杆菌的临床分布及基因组流行病学分析

[背景]鲍曼不动杆菌是造成临床感染的重要病原菌之一,其对碳青霉烯类抗生素的耐药形势日益严重,利用基因组测序技术解析其临床分布特征和流行病学规律有助于临床感染的有效防治.[目的]研究沧州市中心医院2018年检出的200株耐碳青霉烯鲍曼不动杆菌(carbapenem-resistant Acinetobacter baum...     

Metabolic Phenotypes in Pancreatic Cancer

IntroductionThe aim of present study was to profile the glucose-dependent and glutamine- dependent metabolism in pancreatic cancer.MethodsWe performed Immunohistochemical staining of GLUT1, CAIX, BNIP3, p62, LC3, GLUD1, and GOT1. Based on the expression of metabolism-related proteins, the metabolic phenotypes of tumors were classified into two categories, including glucose- and glutamine-dependent metabolism. There were Warburg type, reverse Warburg type, mixed type, and null type in glucose-dependent metabolism, and canonical type, non-canonical type, mixed type, null type in glutamine-dependent metabolism.ResultsLonger overall survival was associated with high expression of BNIP3 in tumor (p = 0.010). Shorter overall survival was associated with high expression of GLUT1 in tumor (P = 0.002) and GOT1 in tumor (p = 0.030). Warburg type of glucose-dependent metabolism had a highest percentage of tumors with nerve infiltration (P = 0.0003), UICC stage (P = 0.0004), and activated autophagic status in tumor (P = 0.0167). Mixed type of glucose-dependent metabolism comprised the highest percentage of tumors with positive marginal status (P<0.0001), lymphatic invasion (P<0.0001), and activated autophagic status in stroma (P = 0.0002). Mixed type and Warburg type had a significant association with shorter overall survival (P = 0.018). Non-canonical type and mixed type of glutamine-dependent metabolism comprised the highest percentage of tumors with vascular invasion (p = 0.0073), highest percentage of activated autophagy in tumors (P = 0.0034). Moreover, these two types of glutamine-dependent metabolism were significantly associated with shorter overall survival (P<0.001). Further analysis suggested that most of tumors were dependent on both glucose- and glutamine-dependent metabolism. After dividing the tumors according to the number of metabolism, we found that the increasing numbers of metabolism subtypes inversely associated with survival outcome.ConclusionWarburg type, non-canonical type and mixed types of glucose- and glutamine-dependent metabolism comprised of more metabolically active, biologically aggressive and poor prognostic tumors. Moreover, the increasing subtypes and categories of the metabolism in each tumor significantly associated with poor prognosis.     

Linc00511 acts as a competing endogenous RNA to regulate VEGFA expression through sponging hsa‐miR‐29b‐3p in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy. Long non‐coding RNAs (lncRNAs) are important regulators in pathological processes, yet their potential roles in PDAC are poorly understood. Here, we identify a fundamental role for a novel lincRNA, linc00511, in the progression of PDAC. Linc00511 levels in PDAC tissue specimens and cell lines were examined by quantitative real‐time PCR. Corresponding adjacent non‐neoplastic tissues were used as controls. The function of linc00511 in PDAC cell lines was determined by RNA interference approach in vitro and in vivo. Fluorescence in situ hybridization (FISH) was used to characterize linc00511 expression in PDAC cells. Insights of the mechanism of competitive endogenous RNAs (ceRNAs) were obtained from bioinformatic analysis, luciferase assays and RIP assays. The association between the linc00511/hsa‐miR29b‐3p axis and VEGFA was verified by Western blotting assay. Immunohistochemistry was performed to evaluate the expression of VEGFA in PDAC samples. The aberrant up‐regulation of linc00511 was detected in PDAC cell lines and patient specimens compared with controls. An increase in linc00511 expression indicates the adverse clinical pathological characteristics and poor prognosis. Functionally, linc00511 depletion in PDAC cells decreased proliferation, migration, invasion and endothelial tube formation. Mechanistically, linc00511 could up‐regulate VEGFA via its competing endogenous RNA (ceRNA) activity on hsa‐miR‐29b‐3p. In summary, our results define an important axis controlling proliferation, invasion and tumour angiogenesis in PDAC. Linc00511 is a novel lncRNA that plays a significant regulatory role in the pathogenesis and progression of PDAC. Thus, Linc00511 represents a new prognostic biomarker to predict clinical outcome of PDAC patients after surgery and may serve as a potential therapeutic target for PDAC treatment.     

HIF‐2α regulates non‐canonical glutamine metabolism via activation of PI3K/mTORC2 pathway in human pancreatic ductal adenocarcinoma

Hypoxia‐inducible factor‐2α (HIF‐2α) plays an important role in increasing cancer progression and distant metastasis in a variety of tumour types. We aimed to investigate its biological function and clinical significance in human pancreatic ductal adenocarcinoma (PDAC). A total of 283 paired PDAC tissues and adjacent normal tissues were collected from patients who underwent surgery or biopsy at Sun Yat‐sen Memorial Hospital between February 2004 and October 2016. In this study, we noted that HIF‐2α expression was significantly up‐regulated in PDAC, positively associated with disease stage, lymph‐node metastasis and patient survival, and identified as an independent prognostic factor of PDAC patients. We demonstrated that HIF‐2α silencing could reduce proliferation, migration and invasion of PDAC cells in vitro. The similar effect on growth was demonstrated in vivo. Furthermore, we noted that knock‐down of HIF‐2α significantly decreased the expression of glutamate oxaloacetate transaminase 1 (GOT1). Importantly, we confirmed that the PI3K/mTORC2 pathway promoted GOT1 expression by targeting HIF‐2α. Our study validated HIF‐2α was an important factor in PDAC progression and poor prognosis and may promote non‐canonical glutamine metabolism via activation of PI3K/mTORC2 pathway. Targeting HIF‐2α represents a novel prognostic biomarker and therapeutic target for patients with PDAC.     

A New Hyperspectral Index for Estimating Copper Content in an Indicative Plant for the Exploration of Copper Deposit

Journal of Plant Growth Regulation - With the rapid development of hyperspectral technology, estimating metal content in plants by establishing the relationship between vegetation indices and metal...