Effect of artesunate on human endometrial carcinoma HEC-1B cells

Objective： To observe the effect of the artesunate （ART） on cellular proliferation in vitro, to search for the possible anti-tumor mechanism of ART on endometrial carcinoma at the molecular level and to provide the experimental and theoretical foundations for the clinical applications of ART. Methods： The cell proliferation was observed by microscope; MTT was used to examine the effects of ART on proliferation of HEC-1B cells, and flow cytometric analysis was used to detect cell cycle and apoptosis. The human endometrial carcinoma HEC-1B cells were conventionally cultured; ART was administered with a concentration of 40 μg/ml before the total RNA were extracted, mRNA expression of Survivin, Caspase-3, N-Cadherin, E-Cadherin, Fibronectinl and Cox-2 were detected using RT-PCR. Results： ART reduced proliferation in human endometrial carcinoma cell line HEC-1B in a dose- and time-dependent effect. The cells of G0/G1 stage were significantly increased （P〈0.05）, but the cells of G2/M stages were significantly decreased （P〈0.05）, so it has shown that the cell cycle was probably blocked in G0/G1 stage. After intervention with ART at 20 and 80 μg/ml for 48 h, cellular apoptosis rate respectively was （36.42±0.77）% and （11.77±0.58）%, and the difference was statistically significant compared with the control （[6.64±0.191%, P〈0.01）. The expression of Cox-2 mRNA in the ART group was lower than those of control group, yet the expression of Caspase-3 and E-Cadherin mRNA in the ART group was higher than those of control group. Conclusion： ART can inhibit HEC-1B cell growth and proliferation in a dose- and time-dependent manner. Furthermore, ART can induce apoptosis in a dose-dependent manner. ART is able to downregulate Cox-2 mRNA expression and to upregulate E-Cadherin and Caspase-3 mRNA expression. So we can conclude that ART could induce the endometrial carcinoma HEC-1B cell apoptosis and inhibit tumor cell proliferation.     

蛇毒精氨酸酯酶Agkihpin上调人肝癌细胞株SMMC-7721中表皮钙黏素的表达研究

目的探讨蛇毒精氨酸酯酶Agkihpin对人肝癌SMMC-7721细胞株中表皮钙黏素(E-CD)表达的影响及Agkihpin抑制人肝癌SMMC-7721细胞的机制。方法采用不同浓度的Agkihpin处理肝癌细胞株72 h后,应用免疫细胞化学、Western Blotting和逆转录PCR(RT-PCR)法检测E-CD在SMMC-7721细胞中的表达。结果不同浓度Agkihpin作用SMMC-7721细胞72 h后E-CD表达均上升,差异有统计学意义(P<0.05),并呈现出一定的剂量依赖效应。Agkihpin可显著上调SMMC-7721细胞中E-CD表达。结论在人低分化肝癌SMMC-7721细胞株中,Agkihpin能促进E-CD的表达,因而可能抑制肝癌细胞的迁移和降低肝癌组织的恶性程度。     

Neuroendocrine and mucinous differentiation in signet ring cell carcinoma of the stomach: evidence for a common cell of origin in composite tumors

Composite tumors are rare neoplasms containing a mixture of 2 different cellular components present in roughly equal proportions. It is hypothesized that composite tumors arise from a multipotential stem cell with subsequent bidirectional differentiation. We present an unusual composite tumor of the stomach composed equally of signet ring cell carcinoma and low-grade neuroendocrine carcinoma. Twenty-one additional patients with signet ring cell carcinomas of the stomach were studied to determine the prevalence of neuroendocrine differentiation by morphology and immunohistochemistry for synaptophysin and chromogranin A. Immunohistochemistry for mucins 5AC and 2 was performed to assess for divergent differentiation toward foveolar and intestinal mucin phenotypes, respectively, and to evaluate for any potential relationship with neuroendocrine differentiation. We found morphologic evidence of neuroendocrine carcinoma in 4 (19%) of 21 consecutive signet ring carcinomas. E-cadherin immunostaining was subsequently performed on these 4 tumors plus the index case. All 5 tumors demonstrated concordance between the signet ring and neuroendocrine components. There was no distinct relationship to mucin 5AC/mucin 2 profiles, with the exception that all 11 intramucosal signet ring cell carcinomas from 4 patients with germ line cadherin 1 gene mutations were composed exclusively of mucin 5AC+ signet ring cells that lacked intestinal mucin and neuroendocrine differentiation. The concordant E-cadherin status in the neuroendocrine and signet ring cell tumor components and the frequent admixture of mucin 5AC+ cells with foveolar differentiation and mucin 2+ cells with intestinal differentiation may support the hypothesis that composite tumors arise from a common stem cell with bilineage or multilineage differentiation.     

上皮-间质转化相关标志物对鼻咽癌远期疗效预测的意义

目的探讨上皮-间质转化(epithelial-mesenchymal transition,EMT)相关标志物神经钙粘连素(N-Cadherin)、上皮钙粘连素(E-Cadherin)、波形蛋白(Vimentin)和Twist在鼻咽癌肿瘤组织中的表达,及其对鼻咽癌复发、转移和预后的意义。方法采用免疫组织化学方法检测77例鼻咽癌组织标本中的E-Cadherin、N-Cadherin、Vimentin和Twist蛋白表达。通过计算机辅助图像分析系统定量分析各EMT相关标志物的表达情况。采用单因素和多因素分析方法评估上述标志物对鼻咽癌复发、转移的预测价值。结果单因素分析显示,E-Cadherin、N-Cadherin、Vimentin和Twist蛋白表达与鼻咽癌复发、转移相关(P<0.05)。多因素分析显示,E-Cadherin和Vimentin是影响鼻咽癌复发、转移的独立风险因素。采用Kaplan-Meier法进行生存分析并作生存曲线。Log-rank检验显示,肿瘤组织内E-Cadherin、N-Cadherin、Twist低表达与高表达患者间生存率均有显著差异(P<0.05),而Vimentin高表达与低表达患者间生存率差异不显著(P=0.055)。结论 E-Cadherin、N-Cadherin、Vimentin和Twist蛋白与鼻咽癌转移、复发密切相关。EMT相关标志物对鼻咽癌侵袭、转移和预后有一定的预测价值。     

Protein expression of brain endothelial cell E-cadherin after hypoxia/aglycemia: influence of astrocyte contact

The blood-brain barrier (BBB) plays a crucial role in protecting the central nervous system (CNS) from any changes in homeostasis brought about by pathological conditions. Cerebrovascular permeability is an important factor in the development of cerebral edema following stroke [M. Plateel, E. Teissier, R. Cecchelli, Hypoxia, dramatically increases the nonspecific transport of blood-borne proteins to the brain. J. Neurochem. 68 (1997) 874-877] and any changes in its function can have detrimental neurological consequences. Recently, research has shown that an in vitro model of the BBB is sensitive to short exposures of hypoxia/aglycemia and that changes in endothelial cell calcium flux may be responsible for structural and functional variations in the BBB during ischemic stress [T.J. Abbruscato, T.P. Davis, Combination of hypoxia/aglycemia compromises in vitro BBB. J. Pharmacol. Exp. Ther. 289 (1999) 668-675]. Present experiments investigated bovine brain microvessel endothelial cell (BBMEC) expression of a Ca(2+)-dependent cell-cell adhesion molecule, E-cadherin, which has been shown to be important for blood-brain barrier function [D. Pal, K.L. Audus, T.J. Siahaan, Modulation of cellular adhesion in bovine brain microvessel endothelial cells by a decapeptide. Brain Research 747 (1997) 103-113]. Since it is believed that astrocyte-endothelial cell interaction is crucial for maintenance of in vivo BBB characteristics, we have attempted to optimize our isolation and culturing techniques to produce a reliable, in vitro model of the BBB that is suitable to study pathological conditions. Immunofluoresence experiments showed positive staining for E-cadherin, yet failed to show any change in cellular distribution of E-cadherin upon hypoxic/aglycemic exposure. In addition, culturing BBMECs with C6 conditioned medium (CM) had no effect on the localization of E-cadherin. Western blotting experiments showed that BBMECs express E-cadherin and this protein is decreased in a time dependent manner after various hypoxic/aglycemic exposures when endothelial cells are cultured alone or with C6 astrogliomas grown on a separate culture surface. When C6 astrocytes are grown directly opposed to endothelial cells, with a porous membrane between, we observed a slight attenuation in the decreased BBMEC expression of E-Cadherin after hypoxia/aglycemia exposure. This work has shown that the mammalian brain endothelial/astrocyte co-culture system is a useful model for studies of pathological conditions where BBB characteristics are maintained.     

华蟾素抑制结肠癌细胞增殖转移的实验研究

目的:观察华蟾素对结肠癌细胞HCT116细胞增殖、迁移的影响,探讨其可能的作用机制。方法:常规体外培养结肠癌细胞HCT116细胞系,采用CCK-8法检测不同浓度华蟾素作用不同时间对HCT116细胞增殖的抑制作用,细胞划痕实验和Transwell小室法检测华蟾素对细胞迁移能力的影响,蛋白质印迹法(Western blot)检测细胞基质金属蛋白酶(MMP)-9、MMP-2、钙黏蛋白(E-Cadherin)的表达水平。结果:CCK-8法检测结果表明,华蟾素对HCT116细胞的生长有明显抑制作用,其抑制作用随药物浓度和作用时间的增加而增强(P0.05);细胞划痕实验和Transwell小室法结果显示,随华蟾素药物浓度的增加,HCT116细胞迁移能力下降(P0.05);Western blot结果表明,华蟾素能够明显抑制HCT116细胞MMP-9的蛋白表达并上调E-Cadherin的蛋白表达(P0.01),但对MMP-2蛋白的表达无显著影响(P0.05)。结论:华蟾素能够抑制人结肠癌细胞的增殖和转移,其机制可能与其抑制MMP-9和上调E-Cadherin的蛋白表达有关。     

5—脱氧杂氮胞苷诱导肝癌细胞E—Cadherin表达增强

目的：研究5－脱氧杂氮胞苷对肝癌细胞株SMMC－7721中E－Cadherin基因表达的影响及其机理。方法：肝癌细胞株SMMC－7721用5－脱氧杂氮胞苷处理,处理前后采用流式细胞仪检测E－Cadherin基因的蛋白表达,观察克隆形成及裸鼠生的变化。结果：经5－脱氧杂氮胞苷处理后,肝癌细胞株SMMC－7721中E－Cadherin蛋白表达增加了43．1％,克隆小而少,裸鼠致瘤性降低。结论：E－Cadherin 基因蛋白表达增高可能与DNA甲基转移酶抑制剂5－脱氧杂氮胞苷抑制了E－Caclherin启动子区域的高甲基化有关,并在一定程度上恢复了其抑癌功能。     

E-cadherin在胃癌中的表达及意义

目的 分析E-cadherin （简称E-CD）在胃癌分化、浸润转移中的作用及其表达的临床意义.方法 应用ABC免疫组化方法研究46例原发性胃癌组织及其转移淋巴结E-CD的表达.结果 54.3%（25/46）的胃癌E-CD表达下降.E-CD的高表达与浸润深度、临床病理分期无关（P＞0.05）,而与胃癌分化程度,Borrmann分型,淋巴结转移有相关性（P＜0.05）.另外,27.3%的中高分化胃癌的转移淋巴结E-CD比原发癌灶表达高,而在低分化胃癌中可达69.2%.结论 E-CD表达下降与胃癌浸润、淋巴结转移及胃癌分化密切相关.