EGCG depresses migration and invasion of human glioma cell line by downregulating COX-2 and MMP-2 expression

AIM: To investigate the mechanism that epigallocatechin-3-gallate (EGCG) depresses the migration and invasion in human glioma cell line SWO-38 by downregulation of cyclocxygenase-2(COX-2) and matrix metalloproteinase-2(MMP-2). METHODS: The effect of EGCG on the apoptosis of SWO-38 cell line was examined by the method of MTT. The migration and invasion of the SWO-38 cells were determined by Transwell assay. The expression of COX-2 and MMP-2 was measured by Western blotting. Meanwhile, TNF-α was used to stimulate the expression of COX-2 for determining if the mechanism of COX-2 pathway is involved in the inhibitory effect of EGCG on the migration and invasion of the tumor cells. RESULTS: After treated with EGCG for 24 h, the migration and invasion abilities of SWO-38 cells were lower than that of the cells before treatment. The results of Western blotting revealed that the 24 h treatment of EGCG on SWO-38 cell line inhibited the expression levels of COX-2 and MMP-2, indicating that the degradation of the extracellular matrix in SWO-38 cells was related to the COX-2 signaling pathway. CONCLUSION: EGCG inhibits the migration and invasion of SWO-38 cell line. The correlation between COX-2 expression and enzymatic degradation in the extracellular matrix determines the abilities of migration and invasion of tumor cells.     

外来入侵种植物学性状和环境因子间关系的典范对应分析

    在浙江金华市郊的不同生境中设立73个样地,通过调查计测样地中外来杂草的生态重要值和34个植物学性状,以及样地中的12个环境因子,分别建立样地-杂草重要值、样地-环境因子和样地-植物学性状3个数据矩阵,应用PC-ORD4.0软件中的典范对应分析模块,探讨杂草分布与环境因子、植物学性状与环境因子间的关系.结果表明:(1)在73个样地中的69个样地被发现有外来杂草分布,共计有32种;(2)典范对应分析表明,土壤水分含量、含沙量、坡度、林冠层郁闭度、土壤翻耕程度、放牧程度、离住宅区距离、建筑程度和交通频度是影响外来杂草分布的主要环境因子;(3)在土壤含水量相对较高的区域,外来杂草多数具有营养繁殖能力、多年生、无地上茎、有根状茎、两侧对称花等植物学性状;(4)在林地中的外来杂草,多数为两年生或具有根状茎、攀缘茎、有棘刺、有毒、叶片较厚等特点;(5)在经常翻耕的土壤中,外来杂草多数为一年生,果实类型多为角果、坚果、胞果等;(6)在住宅周围和交通频繁地段,外来杂草有毒的比例高,种子大、胞果比例较高.     

A focus on the European hamster to illustrate how to monitor endangered species

Agriculture intensification, marked by the generalization of crop monoculture, by the increase in plot size and by the reduction of plant diversity, has led to huge decline in wildlife in European farmlands. In such habitat, research has long been biased towards birds and invertebrates, while very few studies have investigated the effect on small mammals. Considering the European hamster, Cricetus cricetus, we therefore review the different techniques that can be used to investigate the impact of environmental changes and conservation measures in small and endangered wild mammals. We suggest that only a multidisciplinary approach will allow exploration of these effects, combining experimental laboratory work on captive‐bred animals with the monitoring of wild individuals. In particular, individual energy balance has to be investigated and measured as accurately as possible, through either biochemical or bio‐logging techniques. It is, indeed, the most affected physiological trait in a changing environment, as it determines both the reproductive output and the survival of the individual. We also discuss the inconvenience of capture–release approaches for such an endangered species and emphasize the disturbance that experimental protocols could impose on the hamster.     

入侵植物春一年蓬对不同环境的生理适应性研究

为了解上海市郊一种新外来入侵植物春一年蓬对逆境条件的适应能力,测定不同环境胁迫下营养生长时期春一年蓬的膜相对透性、叶绿素、丙二醛、游离脯氨酸和可溶性糖的舍量以及过氧化物酶的活力.与5℃和22℃处理相比,35℃处理的春一年蓬植株的丙二醛、游离脯氨酸、叶绿素含量、过氧化物酶活力和膜相对透性高.用pH 7的溶液处理的春一年篷植株,其体内的膜相对透性、丙二醛、游离脯氨酸和可溶性糖含量低于用pH 10或pH 4的溶液处理的植株.随着其生长环境中NaCl含量的增加或者干旱胁迫,丙二醛、游离脯氨酸、可溶性糖的含量以及膜相对透性也相应地增加.而且,膜相对透性和丙二醛含量与土壤NaCl含量呈明显的正相关.总之,①与高温环境(35℃)相比,春一年蓬更适合生长于低温(5℃)环境;②中生或湿生环境适合春一年蓬的生长,过酸(pH 4)或过碱环境(pH 10)均会对春一年蓬产生有害影响;③春一年蓬对土壤中的NaCl较敏感,在高NaCl(>0.05 mol.L-1)环境中其丙二醛、膜相对透性等均升高.     

Effects of curcumin on migration and invasion of myeloma cells

AIM：To explore the effect of curcumin on the migratory and invasive abilities of myeloma cells. METHODS：shRNA expression plasmid was transfected into RPMI8226 cells to knock down IQ motif-containing GTPase-activating protein 1 (IQGAP1). The expression of IQGAP1 in RPMI8226 cells tranfected with shIQGAP1 or shRNA negative control, and in un-transfected RPMI8226 cells was detected by Western blotting. All the cells in RPMI8226-shIQGAP1 group, RPMI8226-shRNA negative control group and un-transfected RPMI8226 group were treated with curcumin at various concentrations. The migratory and invasive abilities of the RPMI8226 cells were measured by Transwell chamber and Matrigel assays. The expression of IQGAP1 at mRNA and protein levels in the RPMI8226 cells treated with curcumin was also determined by RT-PCR and Western blotting. RESULTS：The expression of IQGAP1 decreased when IQGAP1 gene was knocked down by shRNA. The migration and Matrigel invasion tests showed that the number of cells moving into under chamber of Transwell decreased in RPMI8226-shIQGAP1 group in comparison with the other 2 groups. Curcumin decreased the migratory and invasive abilities of RPMI8226-shRNA negative control cells and un-transfected RPMI8226 cells, which was not related to the curcumin concentratory. The migratory and invasive abilities of RPMI8226-shIQGAP1 cells showed no significant difference when treated with curcumin at various concentrations. The expression of IQGAP1 at mRNA and protein levels decreased in the RPMI8226 cells treated with curcumin. CONCLUSION：Curcumin decreases the migratory and invasive abilities of myeloma cells via inhibition of IQGAP1 expression.     

Effect of GPNMB on proliferation,apoptosis and invasion of human hepatoma cells

AIM：To investigate the effect of glycoprotein nonmetastatic melanoma protein B (GPNMB) on the proliferation, apoptosis and invasion of human hepatoma HepG2 cells and its molecular mechanisms. METHODS：The GPNMB siRNA and GPNMB-overexpressing vector were constructed, and then transfected into HepG2 cells. MTT assay, flow cytometry and Transwell chamber were used to determine the effects of GPNMB down-regulation and up-regulation on the proliferation, apoptosis and invasive ability of HepG2 cells. RESULTS：The proliferation of HepG2 cells was obviously promoted by the up-regulation of GPNMB. No effect of GPNMB on the apoptosis of HepG2 cells was observed. The invasion of HepG2 cells was also significantly promoted by the up-regulation of GPNMB. When integrin β1 was silenced by siRNA, the promoting effect of GPNMB on the proliferation and invasive ability of HepG2 cells was significantly suppressed. CONCLUSION: GPNMB may promote the proliferation and invasion of HepG2 cells by the interaction with integrin β1, and may be used as a potential therapeutic target in liver cancer.     

三叶鬼针草生长特征对土壤氮素水平的响应

利用温室盆栽试验法,研究入侵植物三叶鬼针草生长特征对不同土壤氮素水平的响应。结果表明,氮素的增加能够促进三叶鬼针草叶片数、总叶面积、分枝数及生物量的增加,提高其相对生长速率。在物质分配方面,氮肥的施用能促进该植物向地上部分分配较多的物质,显著增加生殖器官（花）生物量的投入,降低向地下部分（根）的物质投入。同时,可塑性指数表明,三叶鬼针草在形态、生物量分配及生殖器官等方面对土壤氮素响应的表型可塑性较大。以上结果充分体现了三叶鬼针草具有较强的入侵性和对土壤氮素环境较高的适应性,预警人们对其预防和管理工作应加以重视。     

Construction of antisense RNA expression plasmid for u-PAR and its transfection to highly invasive PC-3M cell subclones

AIM: To inhibit specifically the u-PAR expression in highly invasive cell subclones and block its function in those cells invasion. METHODS: A cDNA fragment of u-PAR obtained by RT-PCR was inserted into a plasmid vector named pcDNA3 in the reverse direction. Then an antisense RNA expression plasmid for u-PAR was constructed and transfected into highly invasive cell subclones. The u-PAR expression in resistant cells was examined by RT-PCR and immunohistochemical assay. RESULTS: Compared to the control cells, the content of mRNA and protein of u-PAR in transfected cells decreased sharply, and the rate of inhibition was 53% and 73%, respectively. CONCLUSION: The results indicated that an antisense vector for u-PAR might played a specific inhibitory role in the cells. This model is useful for observing the inhibitory effects of the antisense vector for u-PAR on invasion by highly invasive cell subclones of human prostate carcinoma.     

Tumorigenicity and invasiveness induced by ErbB2 are dependent on FAK

AIM: To explore whether or not ErbB2-induced oncogenic transformation and invasion are mediated by FAK.METHODS: Parental FAK-/- and FAK+/+ cells were used and infected with retrovector particles expressing ErbB2 in order to acquire ErbB2-overexpressed cells,i.e.,FAK-/--ErbB2 and FAK+/+-ErbB2.The role of FAK signaling was explored by analyzing the parameters such as cell survival,invasiveness and tumorigenicity shown by both FAK-/- and FAK+/+ cells in which ErbB2 was overexpressed.RESULTS: ErbB2 was overexpressed and functionally activated in both FAK-/- and FAK+/+ cells upon infection with retrovector particles.The ErbB2-induced anchorage-dependent cell survival,cell invasiveness as well as tumorigenicity in vivo were dependent on FAK.CONCLUSION: FAK is essential for cell survival,tumorigenicity and invasiveness induced by ErbB2,and its possible mechanism involves in ErbB-FAK-Src-MAPK pathway.     

Expression and clinical significance of Bmi-1 in gastric carcinoma

AIM: To investigate the relationship between expression of Bmi-1 (B cell-specific MLV integration site-1) in gastric cancer and its clinicopathologic significance.METHODS: 146 surgical patients with gastric carcinoma were followed up at least 2 years.Expression of Bmi-1 protein was examined by immunohistochemistry in their archival paraffin embedded tissue specimens.RESULTS: The intensive positive rate of Bmi-1 expression in gastric cancer was 67.8% (99/146).Expression of Bmi-1 was highly correlated with tumor size,clinical stage,lymph node metastasis and T classification (P<0.05),but not with sex,age,tumor differentiation,etc.(P>0.05).The survival rate in the patients with Bmi-1 expression was much lower than that in those patients without Bmi-1 expression (P<0.01).Multivariate analysis indicated that Bmi-1 expression,T classification,lymph node metastasis,distant metastasis,tumor size and postoperative chemotherapy were all significantly prognostic factors of gastric carcinoma.CONCLUSION: Overexpression of Bmi-1 in patients with gastric carcinoma enhances the possibility of invasion and metastasis,implying a poor prognosis.Bmi-1 may serve as fairly a good prognostic factor to indicate biologic behavior and prognosis in gastric carcinoma.