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941.
Jingjing Li Beibei Gao Zufa Huang Tong Duan Daiqiang Li Sheng Zhang Yujun Zhao Lian Liu Qiang Wang Zhizhao Chen Ke Cheng 《International journal of clinical and experimental pathology》2015,8(8):9512-9516
MircroRNA functions as a tumor suppressor or a promoter in cholangiocarcinoma (CCA). Researchers have found that miR-203 functioned as tumor suppressor in many types of cancer. However, the role of miR-203 that plays in CCA remains to be clarified. We aimed to detect the expression level and the prognostic significance of miR-203 in CCA tissues. qRT-RCR was performed to examine the miR-203 expression levels in CCA tissue specimens and corresponding normal tissues. Our findings suggest that miR-203 expression was an independent poor prognostic factor for CCA patient overall survival. Therefore, miR-203 may serve as a valuable prognostic marker and promising treatment target for CCA. 相似文献
942.
Wenjia Guo Hailong Tian Xiaogang Dong Jinping Bai Xinling Yang 《International journal of clinical and experimental pathology》2015,8(7):7762-7773
Aims: The present study is to investigate the effect of the combination of small-interfering RNA (siRNA) treatment with bis-chloroethylnitrosourea (BCNU) on the proliferation and apoptosis of glioma cells. Methods: According to different treatments, glioma U251 cells were randomly divided into blank group, Lipofectamine group, siRNA-Gli1 group, BCNU group and combination group. After treatments, the morphology of U251 cells was visualized under the microscope. Afterwards, semi-quantitative real-time polymerase chain reaction and Western blotting were used to determine Gli1, Bcl-2, Bax and cyclin D1 mRNA levels and protein expression, respectively. MTT assay was used detect the proliferation of U251 cells, while flow cytometry was performed to determine cell apoptosis and cell cycle. Results: The combination of siRNA-Gli1 and BCNU caused more severe damages to U251 cell shapes compared with siRNA-Gli1 or BCNU alone. The combination of BCNU and siRNA-Gli1 altered mRNA level and protein expression of Bcl-2 and Bax, but not those of Gli1 and cyclin D1. The combination of siRNA-Gli1 and BCNU promoted U251 cell apoptosis. The combination of siRNA-Gli1 and BCNU enhanced the arrestment of U251 cells in G0/G1 phase. The combination of siRNA-Gli1 and BCNU significantly inhibited U251 cell proliferation. Conclusions: The present study demonstrates that combined treatment with siRNA-Gli1 and BCNU significantly inhibits the proliferation and promotes the apoptosis of glioma U251 cells, possibly by the up-regulation of Bax and the down-regulation of Bcl-2. The combination of siRNA-Gli1 and BCNU enhances the inhibition of cell cycles, but does not down-regulate the expression of cell cycle protein cyclin D1. 相似文献
943.
Ji Cheng Rui Deng Chuanqing Wu Peng Zhang Ke Wu Liang Shi Xinghua Liu Jie Bai Meizhou Deng Jinbo Gao Xiaoming Shuai Guobin Wang Kaixiong Tao 《International journal of clinical and experimental pathology》2015,8(9):10092-10101
Background: SALL4 is a novel oncogene mediating tumorigenesis in multiple carcinomas. However, its actual role and mechanisms participating in the development of colorectal cancer remains unclear. Methods: Immunohistochemical staining and Western blot were conducted to detect the expression of SALL4 and other molecules. siRNA of SALL4 was transfected to silence SALL4 expression in Caco-2 cell line. Flow cytometry was used for cell cycle and apoptosis analysis. Wound healing and transwell assay were used for invasion test. CCK-8 test was employed for cell proliferation and drug sensitivity assessment. Results: By inhibition of SALL4 expression, the proliferation, invasiveness and drug resistance were dramatically reduced while apoptosis rate was up-regulated. Gli1 was found to decrease its expression in SALL4 silencing cells. Moreover, the inhibition on tumorigenesis of Caco-2 by SALL4 silencing was antagonized by Gli1 up-regulation, suggesting Gli1 as a downstream target of SALL4 in cancer development. Conclusion: SALL4 inhibition limited oncogenesis on colorectal cancer by reducing Gli1 expression. 相似文献
944.
目的:探讨3.0代聚酰胺-胺(3.0PAMAM)在牙本质表面诱导生成的矿化物封堵牙本质小管的效果。方法:选取16颗健康正畸牙,制备16个脱矿牙本质样本,按随机数字表法随机选择7个样本作为对照组,7个作为实验组,余2个样本不做任何处理作为脱矿牙本质组。对照组用去离子水处理,实验组用3.0 PAMAM处理之后将各组样本同时浸入人工唾液2、4周后,通过SEM观察每组牙本质小管的微观形貌,X射线能谱仪(EDS)检测牙本质表面沉积物的钙、磷元素含量,并采用两独立样本t检验分析比较4周后2组样本的Ca/P值。结果:SEM观察显示实验组牙本质样本矿化程度随矿化时间延长,表面矿化物逐渐形成,处理4周后完全覆盖所有的牙本质小管口。对照组样本表面矿化物较少,牙本质小管口仍然开放。EDS结果显示沉积物Ca/P值实验组(1.49±0.16)高于对照组(1.18±0.20)(P<0.05)。结论:3.0代聚酰胺-胺对敏感牙本质有一定的生物矿化及封闭作用,在治疗牙本质敏感方面存在潜在价值。 相似文献
945.
目的:探讨血管周细胞瘤的临床病理学特点及诊断要点.方法:对1例血管周细胞瘤进行临床资料、病理形态学及免疫组化观察,并结合文献对其诊断及鉴别诊断进行探讨.结果:本例镜下观肿瘤细胞为梭形,血管丰富,形成弥漫的网状结构,鹿角状的血管将肿瘤细胞分割小叶状,瘤细胞体积较大,胞浆丰富,边界不清,核呈圆形、卵圆形,病理性核分裂相多.免疫组化染色结果显示肿瘤细胞Vimentin(+)、CD34(+)、FVIII(+)、S-100(?)、CEA(?)和GFAP(?).结论:血管周细胞瘤,非常少见,因此缺乏对其认识,从而易与其他肿瘤混淆导致误诊.提高对血管周细胞瘤的认识,对避免误诊是至关重要的. 相似文献
946.
目的 探讨β-catenin和c-Myc在原发性口腔鳞癌(OSCC)中的表达及意义.方法 用免疫组化法检测口腔鳞癌及癌旁正常组织中3-catenin和c-Myc的表达.结果 β-catenin在口腔鳞癌、相应癌旁正常组织中异常表达率分别为56.92%、15.38%,两组之间差异具有统计学意义(P =0.006),β-catenin异常表达增多与肿瘤大小(P=0.003)、局部的淋巴结转移密切相关(P=0.017).在口腔鳞癌、相应癌旁正常组织中c-Myc的阳性表达率为64.62%,7.69%,两组之间差异具有统计学意义(P=0).β-catenin在胞质的表达与c-Myc的表达呈正相关(rs =0.237,P=0.049).结论 c-Myc在口腔鳞癌中过表达,作为原癌基因促进肿瘤发生;β-catenin胞浆异常表达可能与口腔鳞癌的侵袭转移有关. 相似文献
947.
Ming-Xue Piao Ji-Wei Bai Peng-Fei Zhang Ya-Zhuo Zhang 《International journal of clinical and experimental pathology》2015,8(3):2787-2794
Proprotein convertase subtilisin/kexin type 9 (PCSK9), belongs to a family of proprotein convertases (PCs), encodes a neural apoptosis-regulated convertase 1. However, the precise role of PCSK9 during glioma cells apoptosis has not been reported. Therefore, we examined the effects of knockdown and overexpression of PCSK9 on apoptosis of human neuroglioma U251 cells, and investigated the underlying mechanisms of apoptosis. We found that PCSK9 regulated cells proliferation as determined by CCK-8 and Hoechst staining analysis. In addition, western blot results showed that PCSK9 siRNA promote apoptosis via activation of caspase-3 and down-regulation of the anti-apoptotic proteins, XIAP and p-Akt, while PCSK9 overexpression inhibited apoptosis. Moreover, PCSK9 siRNA improved the ratio of Bax/Bcl-2 which leads to the release of cytochrome c, while PCSK9 overexpression decreased it. Taken together, these data demonstrate that PCSK9 may regulate apoptosis through mitochondrial pathway and is expected to be a promising therapeutic strategy for the malignant glioma. 相似文献
948.
949.
Wenqi Bai Yueqin Wu Ping Zhang Yanfeng Xi 《International journal of clinical and experimental pathology》2015,8(10):12333-12345
The efficacy of 5-fluorouracil (5-FU)-based chemotherapy for colorectal cancer (CRC) widely varies among patients; therefore, it is difficult to accurately predict chemotherapeutic responses. Some recent studies have found that key enzymes in the various metabolic pathways activated by 5-FU present potential predictors of treatment outcome. Of these enzymes, thymidylate synthase (TS), thymidine phosphorylase (TP), and dihydropyrimidine dehydrogenase (DPD) are known to play important roles in the efficacy of therapeutic agents. Here, we measured expression levels of TS, TP, and DPD in formalin-fixed, paraffin-embedded, CRC specimens and paracancerous tissue with normal mucosa by immunohistochemical and fluorescence real-time quantitative polymerase chain reaction techniques. We found no significant differences in TS, TP, and DPD expression levels between CRC specimens and paracancerous tissues (P > 0.05), although overall survival and the chemotherapeutic effect were relatively poor in CRC patients with relatively high expression levels of TS, TP, and DPD, as compared to those with comparatively low expression levels (P < 0.05). Therefore, TS, TP, and DPD mRNA levels appear to be suitable indicators of the efficacy of 5-FU-based chemotherapy and prognosis of CRC. 相似文献
950.
Yu-Zhen Zhang Ji-Yu Lou Hong-Ying Bai Yun-Liang Wang Jin-Feng Li Hong-Lei Yin 《International journal of clinical and experimental pathology》2015,8(10):12093-12100
Objective: This study aims to explore the protection effect of bone marrow mesenchymal stem cells (BMSCs) on PC12 cells apoptosis mediated by transient axonal glycoprotein 1 (TAG1). Methods: PC12 cells were divided into control group, Aβ25-35 group and BMSCs + Aβ25-35 group. The effects of BMSCs on PC12 cells treated by Aβ25-35 were detected using MTT, Hoechst 33258 and Annexin V-FITC/PI staining methods. The expression levels of TAG1, β-amyloid precursor protein (APP), AICD and p53 were determined by RT-PCR and Western blotting methods. The expression levels of Bax and Bcl-2 were determined by Western blotting method. The activity of Caspase 3 was detected by spectrophotometric method. Results: MTT results showed that cell activity decreased after the treatment of 20 μM Aβ25-35 for 48 h (P<0.01) while it increased in BMSCs + Aβ25-35 group (P<0.01). Hoechst 33258 and Annexin V-FITC/PI staining results showed that Aβ25-35 could induce the apoptosis of PC12 cells while the apoptosis of PC12 cells was inhibited in BMSCs + Aβ25-35 group. RT-PCR and Western blotting methods showed that 20 μM Aβ25-35 could increase the expression levels of TAG1, APP, AICD and p53 (P<0.01) while they decreased in BMSCs + Aβ25-35 group (P<0.01). 20 μM Aβ25-35 could increase the expression levels of Bax and decrease the expression levels of Bcl-2 (P<0.01), while the expression levels of Bax decreased and the expression levels of Bcl-2 increase in BMSCs + Aβ25-35 group (P<0.01). 20 μM Aβ25-35 could enhance Caspase 3 activity while it decreased in BMSCs + Aβ25-35 group (P<0.01). Conclusions BMSCs with Aβ25-35 could inhibit the apoptosis of PC12 cells, which maybe related with TAG1/APP/AICD signal pathway. 相似文献