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31.
Endometrial cancer is the most common gynecologic malignancy and is associated with increased morbidity each year, including young people. However, its mechanisms of proliferation and progression are not fully elucidated. It is well known that abnormal glycosylation is involved in oncogenesis, and fucosylation is one of the most important types of glycosylation. In particular, fucosyltransferase 8 (FUT8) is the only FUT responsible for α1, 6-linked fucosylation (core fucosylation), and it is involved in various physiological as well as pathophysiological processes, including cancer biology. Therefore, we aimed to identify the expression of FUT8 in endometrial endometrioid carcinoma and investigate the effect of the partial silencing of the FUT8 gene on the cell proliferation of Ishikawa cells, an epithelial-like endometrial cancer cell line. Quantitative real-time PCR analysis showed that FUT8 gene expression was significantly elevated in the endometrial endometrioid carcinoma, compared to the normal endometrium. The immunostaining of FUT8 and Ulex europaeus Agglutinin 1 (UEA-1), a kind of lectin family specifically binding to fucose, was detected endometrial endometrioid carcinoma. The proliferation assay showed FUT8 partial knockdown by transfection of siRNA significantly suppressed the proliferation of Ishikawa cells, concomitant with the upregulation in the gene expressions associated with the interesting pathways associated with de-ubiquitination, aspirin trigger, mesenchymal-epithelial transition (MET) et al. It was suggested that the core fucosylation brought about by FUT8 might be involved in the proliferation of endometrial endometrioid carcinoma cells.  相似文献   
32.
Survivin is an inhibitor of apoptosis as well as a promoter of cell proliferation. Fibulin-3 is a matrix glycoprotein that displays potential for tumor suppression or propagation. The present study aimed to validate the expression levels of survivin and fibulin-3 in benign and malignant respiratory diseases. This case–control study included 219 patients categorized into five groups. Group A included 63 patients with lung cancer, group B included 63 patients with various benign lung diseases, group D included 45 patients with malignant pleural mesothelioma (MPM), and group E included 48 patients with various benign pleural diseases. Group C included 60 healthy individuals (control group). Serum survivin and fibulin-3 levels were measured by ELISA, whereas their nuclear expressions in the lung and pleura were assessed via Western blot analysis. The results showed significantly higher survivin serum levels and significantly lower fibulin-3 levels in group A compared with in group B and controls (P<0.001). There were significantly higher serum levels of survivin and fibulin-3 in group D compared with in group E and controls (P<0.001), consistent with observed nuclear survivin and fibulin-3 expression levels. Fibulin-3 was determined to have higher value than survivin in discriminating lung cancer from MPM (P<0.05). Survivin and fibulin-3 could be useful diagnostic markers for lung and pleural cancers, and fibulin-3 expression was particularly useful in differentiating lung cancer from MPM.  相似文献   
33.
目的:研究子宫内膜癌组织残疾基因同源物2(DAB2)、核连蛋白-2(nucleobindin-2)、黏蛋白4(MUC4)的表达及与预后的关系。方法:将我院从2015年1月2017年1月收治的子宫内膜癌患者82例纳入研究。分别采集所有患者的子宫内膜癌组织以及癌旁正常组织,以免疫组化法检测不同子宫内膜组织中的DAB2、nucleobindin-2、MUC4表达情况并进行对比。分析子宫内膜癌组织DAB2、nucleobindin-2、MUC4阳性率与临床病理特征的关系。此外,通过Kaplan-Merier生存曲线分析上述蛋白表达与预后的关系,并以Cox比例风险回归模型分析子宫内膜癌患者预后的影响因素。结果:子宫内膜癌组织DAB2阳性率低于癌旁正常组织,而nucleobindin-2、MUC4阳性率均高于癌旁正常组织(均P<0.05)。TNM分期ⅢⅣ期、淋巴结转移子宫内膜癌患者的DAB2阳性率低于TNM分期ⅠⅡ期、无淋巴结转移患者,而nucleobindin-2、MUC4阳性率均高于TNM分期ⅠⅡ期、无淋巴结转移患者(均P<0.05)。所有患者均进行时长360个月的随访,中位随访时间为31个月,至随访结束,DAB2蛋白阳性患者的无进展生存率分别为66.67%(20/30),明显高于DAB2蛋白阴性患者的19.23%(10/52);而nucleobindin-2、MUC4蛋白阳性患者的无进展生存率分别为22.95%(14/61)、24.56%(14/57),明显低于nucleobindin-2、MUC4蛋白阴性患者的76.19%(16/21)、64.00%(16/25),差异均有统计学意义(均P<0.05)。Cox比例风险回归模型分析结果可得:TNM分期、淋巴结转移以及DAB2蛋白阴性、nucleobindin-2蛋白阳性、MUC4蛋白阳性均是子宫内膜癌患者预后的影响因素(均P<0.05)。结论:子宫内膜癌组织DAB2存在异常低表达,而nucleobindin-2、MUC4均存在异常高表达,联合检测上述三项蛋白表达情况可能有助于子宫内膜癌的诊断和预后评估。  相似文献   
34.
摘要 目的:探讨复方醋酸棉酚片联合独一味胶囊对大鼠无排卵型功能失调性子宫出血的改善作用及其作用机制。方法:将40只雌性SD大鼠随机均分成两组(空白组和模型组),采用给大鼠连续21 d灌胃戊酸雌二醇的方法制备无排卵型功能失调性子宫大鼠模型。模型大鼠制备成功后,按随机法再均分成模型组、阳性组和治疗组,其中阳性组和治疗组分别灌胃给予相应的药物,空白组和模型组灌胃等体积的生理盐水,各组均连续灌胃7 d。计算各组大鼠的子宫系数,采用酶联免疫吸附法测定大鼠血清中雌二醇(estradiol, E2)和孕酮(progestone,P)水平,采用免疫组化法测定大鼠子宫内膜组织中两个蛋白(matrix metalloproteinases-9,MMP-9和vascular endothelial growth factor ,VEGF)的表达量。结果:模型组大鼠血清中的P水平比空白组显著性减少(P<0.05),子宫内膜组织中的MMP-9和VEGF表达量比空白组均显著性升高(P<0.05)。给药后,治疗组和阳性组大鼠血清中的P水平均显著高于模型组(P<0.05),大鼠子宫内膜组织中的MMP-9和VEGF 表达量均显著低于模型组(P<0.05),治疗组与阳性组之间无显著性差异(P >0.05)。结论:复方醋酸棉酚片联合独一味胶囊对无排卵型功能失调性子宫出血具有明显的改善作用,其机制可能与调控子宫内膜 MMP-9 和VEGF的表达量有关。  相似文献   
35.
目的:探讨2型糖尿病(T2DM)患者血糖波动与心律失常和下肢血管病变的关系,分析影响T2DM心律失常和下肢血管病变的因素。方法:选择2019年7月到2020年6月我院收治的82例T2DM患者,根据是否合并心律失常分为心律失常组28例和无心律失常组54例,根据是否合并下肢血管病变分为下肢血管病变组31例和无下肢血管病变组51例。所有患者均通过72 h监测血糖获得日内平均血糖波动幅度(MAGE)、日间血糖平均绝对差(MODD)、全天血糖标准差(SDBG)、全天血糖波动次数(NGE)。比较组间差异,分析影响T2DM患者心律失常和下肢血管病变的因素。结果:心律失常组MAGE、MODD、SDBG、NGE、糖化血红蛋白(HbA1c)、胰岛素抵抗指数(HOMA-IR)、T2DM病程、同型半胱氨酸(Hcy)、丙二醛(MDA)高于无心律失常组(P<0.05)。下肢血管病变组T2DM病程、Hcy、MDA、HOMA-IR、MAGE、MODD、SDBG、NGE均高于无下肢血管病变组(P<0.05)。Logistic回归分析结果显示MDA、HOMA-IR、MAGE、MODD是T2DM患者心律失常的危险因素(P<0.001),MAGE、MODD、SDBG是T2DM患者下肢血管病变的危险因素(P<0.001)。结论:T2DM患者血糖波动与心律失常和下肢血管病变均有关,血糖波动增加是T2DM心律失常和下肢血管病变的危险因素。  相似文献   
36.
PurposeEndometrial carcinoma (EC) is a clinically heterogeneous disease characterized by a number of different histological subtypes, and its heterogeneity may be involved in the accumulation of multiple genetic alterations. The aim of this work was to investigate the comprehensive mutational profile of EC tumors, and examine the associations between somatic mutations and clinicopathological features or survival in EC patients.MethodsA total of 100 surgical tumors were obtained from EC patients who had previously undergone surgery. Genomic DNA samples extracted from fresh-frozen tissues were analyzed using the Ion AmpliSeq Cancer Hotspot Panel v2 Kit, covering 50 tumor-related genes.ResultsValidated mutations were detected in 91 of the 100 tumors (91%) and identified in eight of the most frequently mutated genes, namely PTEN (57%), PIK3CA (51%), TP53 (30%), KRAS (23%), CTNNB1 (21%), FBFR2 (13%), FBXW7(10%) and RB1 (9%). PTEN mutations were found to associated with young age (< 60), early-stage, endometrioid histology, non-recurrence and better overall survival (OS). CTNNB1 mutations were associated with young age, endometrioid histology and better OS. On the other hands, TP53 mutations were associated with late-stage, non-endometrioid histology, high-grade, recurrence and worse OS. FBWX7 mutations were associated with late-stage, vascular invasion and lymph node metastasis. FGFR2 mutations correlated with deep (≥ 1/2) myometrial invasion.ConclusionOur comprehensive mutational profile will be useful for understanding and evaluating the molecular characteristics of EC tumors, and may lead to the establishment of novel treatment strategies that improve the survival of patients with EC in the future.  相似文献   
37.
The ability to add or delete specific genes in swine will likely provide considerable benefits not just to agriculture but also to medicine, where pigs have potential as models for human disease and as organ donors. Here we have transferred nuclei from a genetically modified fibroblast cell line to porcine oocytes, matured in vitro under defined culture conditions, to create piglets expressing enhanced green fluorescent protein. The nuclear transfer-derived piglets were of normal size, although some mild symptoms of “large offspring syndrome” were evident. These experiments represent a next step towards creating swine with more useful genetic modifications.  相似文献   
38.
Human papilloma virus (HPV) infection is the main etiological factor for cervical intraepithelial lesions (CIN). An important characteristic of this process is the loss of genome stability. Therefore, it is imperative to use biomarkers of DNA damage caused by genomic instability to identify high risk individuals. We investigated the frequency of micronuclei (MN) in peripheral blood lymphocytes (PBL) of 20 patients, diagnosed as histologically CIN 1 and 10 healthy controls. We also examined the frequency of other nuclear anomalies including nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) in PBL of patients with CIN 1 and healthy controls, and evaluated the benefits of p16INK4a and Ki-67 (p16INK4a/Ki-67) immunohistochemical double staining for identifying cervical squamous cells that express HPV E6/E7 oncogenes. We analyzed the association between the frequency of MN in PBL and the amount of p16INK4a/Ki-67 co-expression in CIN 1 patients to establish genomic instability. Among CIN 1 subjects, 15% exhibited diffuse p16INK4a/Ki-67 co-expression and were considered high positive, 25% of the CIN 1 cases exhibited p16INK4a/Ki-67 co-expression restricted to the lower part of the epithelium and were considered low positive and the remaining 60% of cases were negative. The frequency of MN, NPBs and NBUDs differed significantly among groups. We found a statistically significant positive correlation between p16INK4a/Ki-67 co-expression and the frequency of MN, NPBs and NBUDs in PBL. Our findings demonstrate the efficacy of p16INK4a/Ki-67 double immunostaining for histological samples with CIN 1. MN frequency in PBL might be useful for detecting genomic instability in cases of HPV infection and CIN.  相似文献   
39.
Reactive oxygen species (ROS) released from polymorphonuclear leukocytes and macrophages could cause DNA damage, but also induce cell death. Therefore inhibition of cell death must be an important issue for accumulation of genetic changes in lymphoid cells in inflammatory foci. Scavengers in the post culture medium of four lymphoid cell lines, lymphoblastoid cell lines (LCL), Raji, BJAB and Jurkat cells, were examined. Over 80% of cultured cells showed cell death 24 h after xanthine (X)/xanthine oxidase (XOD) treatment, which was suppressed by addition of post culture medium from four cell lines in a dose-dependent manner. H2O2 but not O·-2 produced by the X/XOD reaction was responsible for the cytotoxity, thus we used H2O2 as ROS stress thereafter. The H2O2-scavenging activity of post culture media from four cell lines increased rapidly at the first day and continued to increase in the following 2–3 days for LCL, Raji and BJAB cells. The scavenging substance was shown to be pyruvate, with various concentrations in the cultured medium among cell lines. Over 99% of total pyruvate was present in the extracellular media and less than 1% in cells. α-Cyano-4-hydroxycinnamate, a specific inhibitor of the H+-monocarbohydrate transporter, increased the H2O2-scavenging activity in the media from all four cell lines via inhibition of pyruvate re-uptake by cultured cells from the media. These findings suggest that lymphoid cells in inflammatory foci could survive even under ROS by producing pyruvate, so that accumulation of lymphoid cells with DNA damage is possible.  相似文献   
40.
Abstract

Mutation of the proto-oncogene K-Ras is one of the most common molecular mechanisms in non-small cell lung cancer. Many drugs for treating lung cancer have been developed, however, due to clinical observed K-Ras mutations, corresponding chemotherapy and targeted therapy for such mutation are not efficient enough. In this study, on the basis of the crystal structure of K-Ras, 21 analogues (TKR01–TKR21) containing urea or thiourea were rationally designed, which can effectively inhibit the lung cancer cell A549 growth. The designing of these compounds was based on the structure of K-Ras protein, and the related groups were replaced by bioisosteres to improve the affinity and selectivity. Biological testing revealed that compound TKR15 could significantly inhibit the proliferation of A549 cell with IC50 of 0.21?µM. Docking analysis showed that the TKR15 can effectively bind to the hydrophobic cavity and form a hydrogen bond with the Glu37. In addition, through flow apoptosis assay and immunofluorescence staining assay, it confirmed that this compound can inhibit A549 cell proliferation with the mechanism of blocking K-RasG12V protein and effector proteins interactions through the apoptotic pathway. In conclusion, our studies in finding novel potent compound (TKR15) with confirmed mechanism showed great potential for further optimisation and other medicinal chemistry relevant studies.  相似文献   
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