ROCK1基因敲除 对乳腺癌细胞系迁移及侵袭的影响

目的：通过成簇规律间隔的短回文重复序列（CRISPR/Cas9）系统在MCF-7乳腺癌细胞系中构建Rho相关蛋白激酶1（ROCK1）基因敲除模型,研究ROCK1敲除对乳腺癌细胞迁移及侵袭能力的影响。方法：设计并合成靶向ROCK1的向导RNA （sgRNA）寡核苷酸序列,长度为20 bp,构建到CRISPR单载体慢病毒上,感染并筛选稳定细胞株,采用划痕实验和Transwell实验分别检测细胞迁移和侵袭能力。结果：目的sgRNA寡核苷酸双链成功插入酶切后的GV392质粒载体中且测序正确;经Western blot鉴定ROCK1敲除的细胞株构建成功;ROCK1基因敲除后,与对照组细胞相比,其蛋白表达缺失。划痕实验结果显示ROCK1敲除细胞株24 h划痕愈合度为（60.600±0.047）%,对照组细胞划痕愈合度为（80.404±0.018）%,差异有统计学意义（P=0.003）。Transwell实验结果显示ROCK1敲除细胞株在24 h的迁移细胞数为（271.3±5.0）个,对照组的迁移细胞数为（448.3±5.5）个;48 h的迁移细胞数在实验组和对照组分别为（1.7±2.9）个和（298.3±5.7）个,差异有统计学意义（P=0.000）。结论：ROCK1基因敲除可明显抑制乳腺癌细胞的迁移及侵袭能力,提示ROCK1基因在乳腺癌侵袭和转移中可能发挥重要作用。     

DKK1对乳腺癌细胞迁移侵袭能力影响的研究

  目的  探讨Dikkopf 1（DKK1）对乳腺癌细胞迁移侵袭能力的影响。  方法  采用免疫组织化学方法检测DKK1在乳腺癌组织中的表达,并通过免疫荧光对DKK1在细胞中的定位进行分析;DKK1过表达的真核表达载体转染乳腺癌细胞MDA231,应用Western blot检测转染后乳腺癌细胞MDA231中DKK1蛋白表达水平。划痕实验检测转染后MDA231细胞的迁移能力,Transwell实验检测MDA231细胞侵袭能力的改变。  结果  免疫组织化学检测到乳腺癌组织原发病灶及转移病灶DKK1表达明显高于对应的癌旁组织（P < 0.05）。DKK1表达的阳性率在有淋巴结转移组织中明显比无淋巴结转移组织中低。免疫荧光结果显示DKK1主要呈细颗粒状散在分布于细胞质中。Western blot检测表明DKK1过表达明显。过表达DKK1的MDA231细胞迁移和侵袭能力明显比阴性对照组和空白组低。  结论  DKK1的表达与乳腺癌细胞迁移和侵袭能力呈负相关。      

TAGLN基因过表达对乳腺癌细胞迁移和侵袭能力的影响

目的 研究TAGLN基因过表达对人乳腺癌细胞MDA-MB-231迁移能力和侵袭能力的影响及其分子机制.方法 对MDA-MB-231细胞采用慢病毒表达系统构建TAGLN基因稳定过表达细胞株,将MDA-MB-231细胞正常培养设为空白对照组,空载体慢病毒包装感染MDA-MB-231细胞后获得的稳定转染细胞株设为空载体对照组.Real time PCR和Western blot检测TAGLN mRNA和蛋白表达,划痕实验和Transwell侵袭实验检测细胞迁移和侵袭能力,Western blot检测TAGLN基因过表达后基质金属蛋白酶2(matrix metalloproteinase-2,MMP-2)和MMP-9蛋白表达变化.结果 MDA-MB-231细胞感染TAGLN基因过表达慢病毒载体后,细胞中TAGLN mRNA表达和蛋白表达升高(均P＜0.01),成功构建TAGLN基因过表达稳定细胞株(231-TAGLN).231-TAGLN细胞的体外迁移能力和侵袭能力下降,与空载体对照组和空白对照组细胞比较,差异均具有统计学意义(均P＜0.01),同时伴有MMP-2和MMP-9表达水平降低(均P＜0.01).结论 TAGLN基因过表达可以抑制乳腺癌细胞的迁移和侵袭,MMP-2和MMP-9基因表达下降可能参与这一过程.     

CXCL12 promotes CCR7 ligand–mediated breast cancer cell invasion and migration toward lymphatic vessels

Chemokines are a family of cytokines that mediate leukocyte trafficking and are involved in tumor cell migration, growth, and progression. Although there is emerging evidence that multiple chemokines are expressed in tumor tissues and that each chemokine induces receptor‐mediated signaling, their collaboration to regulate tumor invasion and lymph node metastasis has not been fully elucidated. In this study, we examined the effect of CXCL12 on the CCR7‐dependent signaling in MDA‐MB‐231 human breast cancer cells to determine the role of CXCL12 and CCR7 ligand chemokines in breast cancer metastasis to lymph nodes. CXCL12 enhanced the CCR7‐dependent in vitro chemotaxis and cell invasion into collagen gels at suboptimal concentrations of CCL21. CXCL12 promoted CCR7 homodimer formation, ligand binding, CCR7 accumulation into membrane ruffles, and cell response at lower concentrations of CCL19. Immunohistochemistry of MDA‐MB‐231–derived xenograft tumors revealed that CXCL12 is primarily located in the pericellular matrix surrounding tumor cells, whereas the CCR7 ligand, CCL21, mainly associates with LYVE‐1⁺ intratumoral and peritumoral lymphatic vessels. In the three‐dimensional tumor invasion model with lymph networks, CXCL12 stimulation facilitates breast cancer cell migration to CCL21‐reconstituted lymphatic networks. These results indicate that CXCL12/CXCR4 signaling promotes breast cancer cell migration and invasion toward CCR7 ligand–expressing intratumoral lymphatic vessels and supports CCR7 signaling associated with lymph node metastasis.     

Cancer-associated fibroblasts affect breast cancer cell gene expression,invasion and angiogenesis

Purpose

It has been reported that stromal cell features may affect the clinical outcome of breast cancer patients. Cancer associated fibroblasts (CAFs) represent one of the most abundant cell types within the breast cancer stroma. Here, we aimed to explore the influence of CAFs on breast cancer gene expression, as well as on invasion and angiogenesis.

Methods

qRT-PCR was used to evaluate the expression of several cancer progression related genes (S100A4, TGFβ, FGF2, FGF7, PDGFA, PDGFB, VEGFA, IL-6, IL-8, uPA, MMP2, MMP9, MMP11 and TIMP1) in the human breast cancer-derived cell lines MCF-7 and MDA-MB-231, before and after co-culture with CAFs. Stromal mononuclear inflammatory cell (MIC) MMP11 expression was used to stratify primary tumors. In addition, we assessed the in vitro effects of CAFs on both MDA-MB-231 breast cancer cell invasion and endothelial cell (HUVEC) tube formation.

Results

We found that the expression levels of most of the genes tested were significantly increased in both breast cancer-derived cell lines after co-culture with CAFs from either MMP11+ or MMP11- MIC tumors. IL-6 and IL-8 showed an increased expression in both cancer-derived cell lines after co-culture with CAFs from MMP11+ MIC tumors. We also found that the invasive and angiogenic capacities of, respectively, MDA-MB-231 and HUVEC cells were increased after co-culture with CAFs, especially those from MMP11+ MIC tumors.

Conclusions

Our data indicate that tumor-derived CAFs can induce up-regulation of genes involved in breast cancer progression. Our data additionally indicate that CAFs, especially those derived from MMP11+ MIC tumors, can promote breast cancer cell invasion and angiogenesis.

     

Osteopontin increases breast cancer cell sensitivity to specific signaling pathway inhibitors in preclinical models

Src kinase and Hsp90 play important roles in malignancy-promoting signaling pathways in a variety of cancers and related targeting agents are presently in clinical trials. To help improve the success of Src kinase and Hsp90 inhibitor therapies, identifying sensitive patient populations will be essential. Osteopontin (OPN), a secreted integrin-binding glycophosphoprotein, is associated with progression and metastasis in a variety of cancers and has been studied as a prognostic marker. Previous work of ours and other groups has indicated that OPN-induced signal transduction involves activation of both Src and Hsp90-dependent pathways. We thus hypothesized that over-expression of OPN could make tumor cells more vulnerable to these classes of inhibitors. This study used multiple in vitro assays to determine if OPN levels could predict breast cancer cell sensitivity to Hsp90 and/or Src kinase inhibitors. We used multiple derivatives of two unrelated of human breast cancer cell lines, high vs. low levels of OPN, to determine if OPN affects the response to two specific inhibitors, an Hsp90 inhibitor and a Src kinase inhibitor, in in vitro migration and colony formation assays. Cells had greater decreases in migration and colony forming ability after Hsp90 and Src kinase inhibitor treatments when OPN was present (either endogenous or exogenous). Decreasing OPN levels via shRNA knockdown decreased inhibitor effects. In rescue experiments, adding exogenous OPN to non-expressing cells increased inhibitor effects. These results suggest that OPN could potentially be useful clinically as a predictive marker in identifying patients who will benefit from either Hsp90 or Src kinase inhibitor therapy.     

VEGF-C反义寡核苷酸对乳腺癌细胞MDA-MB-435黏附、侵袭能力的影响

目的　探讨 VEGF- C反义寡核苷酸 (antisense oligodeoxynucleotide,ASODN )对人乳腺癌细胞 MDA-MB- 4 35黏附、侵袭能力的影响。方法　以 VEGF- C基因编码区为靶点合成反义寡核苷酸 ,脂质体介导转染。 RT-PCR法检测转染后 VEGF- C m RNA表达水平 ;MTT法检测乳腺癌细胞与细胞外基质黏附 ;利用 Transwell小室 ,检测乳腺癌细胞侵袭人工基底膜能力 ;Western- blot法检测乳腺癌细胞中 MMP- 2蛋白表达。结果　与空白对照及正义序列 (sense oligodeoxynucleotide,SODN)转染组比较 ,ASODN组 VEGF- C m RNA水平下调 ,差异有显著性 (t=5 .6 4 ,5 .4 8,P<0 .0 1) ;对胞外基质黏附率明显降低 (χ2 =7.15 ,7.2 9,P<0 .0 5 ) ,穿透重组基底膜数目显著下降 (t=5 .2 9,5 .17,P<0 .0 1) ;细胞裂解液中 MMP- 2蛋白表达显著下调 (t=7.36 ,7.4 3,P<0 .0 1)。结论　 VEGF- C基因 ASODN脂质体介导转染可明显抑制乳腺癌细胞体外实验中的黏附和侵袭能力 ;下调 MMP- 2的表达可能是其作用途径。     

干扰LOX表达对MDA-MB-231细胞侵袭迁移影响及其机制的探讨

目的:研究干扰赖氨酰氧化酶(LOX)基因表达对乳腺癌细胞MDA-MB-231体外侵袭迁移能力的影响,并探讨相关机制及意义。方法:设计合成特异性慢病毒干扰载体(LOX-RNAi-LV)转染MDA-MB-231细胞,实时定量PCR检测LOX mRNA和侵袭转移相关因子MMP-2、MMP-9和HIF-1α的mRNA表达,蛋白质印迹法检测LOX蛋白表达,细胞侵袭迁移实验(Transwell)检测细胞侵袭迁移能力。结果:转染LOX-RNAi-LV后,乳腺癌MDA-MB-231细胞LOXmRNA和蛋白表达水平明显降低,与空白组相比,抑制率分别为89.2%和82.97%。MMP-2(F=225.271,P=0.0000)、MMP-9(F=35.373,P=0.000 01)和低氧诱导因子HIF-1α(F=341.081,P=0.0000)的mRNA表达均明显降低。细胞侵袭迁移实验显示,干扰组穿过Transwell小室滤过膜的细胞数明显少于对照组(侵袭实验F=269.557,P=0.000 5;迁移实验F=164.321,P=0.000 3)。结论:转染LOX-RNAi-LV能有效地干扰LOX在乳腺癌细胞MDA-MB-231中表达,抑制肿瘤细胞的侵袭和迁移能力,其作用机制可能与下调MMP-2、MMP-9和HIF-1α表达有关。     

P65基因对人三阴性乳腺癌细胞MDA-MB-231体外侵袭的影响

目的:观察miRNA靶向沉默P65基因对人三阴性乳腺癌(triple-negative breast cancer,TNBC)MDA-MB-231细胞体外黏附和侵袭的影响及其可能机制。方法:设计3对针对P65基因的特异性miRNA(P65miRNA-1、P65miRNA-2和P65miRNA-3),转染MDA-MB-231细胞,Western blotting检测P65蛋白的表达,筛选沉默效果最好的miRNA进行后续实验。体外黏附实验和Transwell小室实验检测P65miRNA转染前后MDA-MB-231细胞的黏附和侵袭。RT-PCR检测MDA-MB-231细胞基质金属蛋白酶-2(matrix metalloproteinase-2,MMP-2)、MMP-9 mRNA的表达水平,明胶酶谱法检测MDA-MB-231细胞中MMP-2、MMP-9的酶活性。结果:成功构建重组质粒P65miRNA-1、P65miRNA-2和P65miRNA-3,前两者转染MDA-MB-231细胞后抑制P65蛋白表达80%以上。P65miRNA-1和P65miRNA-2转染对MDA-MB-231细胞的黏附无明显影响(P>0.05),但显著抑制MDA-MB-231细胞的侵袭(0.371±0.039、0.309±0.046 vs 0.698±0.065,P<0.05)。P65miRNA-1和P65miRNA-2转染沉默P65表达后,MDA-MB-231细胞MMP-2 mRNA(0.281±0.018、0.478±0.023 vs 1.056±0.072、1.128±0.059,P<0.05)和MMP-9 mRNA表达(0.193±0.013、0.371±0.035 vs 1.206±0.069、1.089±0.057,P<0.05)及其活性均显著下调。结论:miRNA靶向沉默P65的表达能抑制人TNBC MDA-MB-231细胞的体外侵袭,其机制可能与抑制MMP-2、MMP-9的表达和活性有关。     

Ets‐1 controls breast cancer cell balance between invasion and growth

Ets‐1 overexpression in human breast cancers is associated with invasiveness and poor prognosis. By overexpressing Ets‐1 or a dominant negative mutant in MMT breast cancer cells, we previously highlighted the key role of Ets‐1 in coordinating multiple invasive features of these cells. Interestingly, we also noticed that Ets‐1 decreased the density of breast cancer cells cultured in three‐dimensional extracellular matrix gels. The 3D context was instrumental to this phenomenon, as such downregulation was not observed in cells grown on two‐dimensional plastic or matrix‐coated dishes. Ets‐1 overexpression was deleterious to anchorage‐independent growth of MMT cells in soft agar, a standard model for in vitro tumorigenicity. The relevance of this mechanism was confirmed in vivo, during primary tumor growth and in a metastatic assay of lung colonization. In these models, Ets‐1 was associated with epithelial‐to‐mesenchymal transition features and modulated the ratio of Ki67‐positive cells, while hardly affecting in vivo apoptotic cell death. Finally, siRNA‐mediated knockdown of Ets‐1 in human breast cancer cell lines also decreased colony growth, both in anchorage‐independent assays and 3D extracellular matrix cultures. These in vitro and in vivo observations shed light on an unsuspected facet of Ets‐1 in breast tumorigenesis. They show that while promoting malignancy through the acquisition of invasive features, Ets‐1 also attenuates breast tumor cell growth and could therefore repress the growth of primary tumors and metastases. This work also demonstrates that 3D models may reveal mechanisms of tumor biology that are cryptic in standard 2D models.     

PTEN基因转染对人膀胱癌细胞系BIU87增殖及侵袭活性的影响

背景与目的:PTEN(phosphataseandtensinhomologuedeletedfromchromosome10)是迄今为止发现的第一个具有磷酸酶活性的抑癌基因,在多种原发性恶性肿瘤和肿瘤细胞株中均存在有较高频率的缺失或突变,其失活与肿瘤的进程和预后相关。本实验研究外源性PTEN转染后,人膀胱癌细胞系BIU87增殖和侵袭活性的改变。方法:将携有PTEN基因的重组真核表达质粒pBp-PTEN转化大肠杆菌DH5α并扩增,抽提纯化质粒并进行酶切鉴定,pBp-PTEN体外转染BIU87细胞(pBp-PTEN-BIU87),筛选稳定转染的细胞并扩增培养,以转染了空质粒pBp的BIU87细胞(pBp-BIU87)和正常BIU87细胞为对照,用RT-PCR检测PTEN的表达情况,并用四甲基偶氮唑蓝比色法(MTT法)和细胞侵袭实验分别检测PTEN基因转染前、后BIU87细胞增殖和侵袭活性的变化。结果:pBp-PTEN的酶切鉴定证实含有目的基因PTEN;pBp-PTEN-BIU87细胞的RT-PCR产物经凝胶电泳有明显的阳性条带,而对照组则无;MTT发现,pBp-PTEN-BIU87细胞在第2、3和4天的吸光度(A值)明显低于两对照组(P<0.05),以正常BIU87细胞为对照,PTEN基因在第1、2、3、4天的细胞生长抑制率分别为4.27%、18.92%、19.54%、17.69%。细胞侵袭试验显示,各组细胞浸润穿透ECM膜的数目:pBp-PTEN-BIU8为39.3±7.7,BIU87和pBp-BIU87分别为48.1±13.2和48.9±11.0,pBp-PTEN-BIU87细胞明显少于两对照组(P<0.05)。结论:抑癌基因PTEN转染能降低膀胱癌细胞的增殖和侵袭活性。     

SRC激酶抑制剂对前列腺癌细胞侵袭与增殖的影响

目的：以PP2[4-Amino-5-（4-Chloro-Phenyl）-7-（t-Butyl）Pyrazolo（3,4-d）Pyrimidine]药物（src激酶抑制剂）处理前列腺癌细胞,检测src激酶及E-cadherin蛋白表达水平的变化,探讨PP2对前列腺癌细胞增殖和侵袭能力的影响。方法：PP2处理前列腺癌细胞PC-3,Western blot检测src及其相关蛋白的表达;Boyden小室实验检测细胞侵袭能力;MTT检测细胞的增殖能力。结果：PP2处理PC-3细胞后,src表达水平明显降低,E-cadherin表达水平升高;细胞的增殖和侵袭能力均受到明显抑制,剂量越高抑制作用越明显（P〈0.05）。结论：PP2通过提高细胞黏附分子E-cadherin的表达抑制前列腺癌细胞PC-3的增殖和侵袭能力。     

SRC激酶抑制剂对前列腺癌细胞侵袭与增殖的影响

目的:以PP2[4-Amino-5-(4-Chloro-Phenyl)-7-(t-Butyl)Pyrazolo(3,4-d)Pyrimidine]药物(src激酶抑制剂)处理前列腺癌细胞,检测src激酶及E-cadherin蛋白表达水平的变化,探讨PP2对前列腺癌细胞增殖和侵袭能力的影响。方法:PP2处理前列腺癌细胞PC-3,Western blot检测src及其相关蛋白的表达;Boyden小室实验检测细胞侵袭能力;MTT检测细胞的增殖能力。结果:PP2处理PC-3细胞后,src表达水平明显降低,E-cadherin表达水平升高;细胞的增殖和侵袭能力均受到明显抑制,剂量越高抑制作用越明显(P<0.05)。结论:PP2通过提高细胞黏附分子E-cadherin的表达抑制前列腺癌细胞PC-3的增殖和侵袭能力。     

逆转录病毒介导重组CXCR4对前列腺癌细胞侵袭力的影响

目的:构建CXCR4基因重组逆转录病毒表达载体pLEGFP-CXCR4,并转染PC-3细胞,探讨趋化因子受体CXCR4对人前列腺癌细胞体外侵袭能力的影响.方法: 分离健康人外周血单个核细胞,提取总RNA,以其为模板, RT-PCR法扩增CXCR4,获取CXCR4基因全长序列,装入带有绿色荧光蛋白(GFP)的逆转录病毒质粒pLEGFP-N1,用脂质体法转染PC-3细胞,采用实时定量PCR和Western blotting观察CXCR4表达情况,并通过体外细胞-基质粘附试验和Transwells小室检测肿瘤细胞体外侵袭能力的变化.结果: 成功构建pLEGFP-CXCR4载体,转染人前列腺癌细胞 72h后,CXCR4 mRNA及蛋白质水平明显上调,细胞的体外侵袭力明显增强,增殖活性增强.结论: CXCR4转染能够明显提高CXCR4基因mRNA及蛋白水平,提高人前列腺癌细胞体外侵袭能力.     

Role of Src in breast cancer cell migration and invasion in a breast cell/bone-derived cell microenvironment

The preferential metastasis of breast cancer cells to bone comprises a complex set of events including homing and preferential growth, which may require unique factors produced by bone or other cells in the immediate microenvironment. In this study, an in vitro co-culture system composed of bone mesenchymal stem cells and breast cancer cell lines is used to examine the role of Src kinase on breast cancer cell migration and invasion in the presence of bone-derived cells. This research shows that Src kinase activity in breast cancer cell lines with either high or low levels of endogenous Src activity is increased by bone-derived cell-conditioned medium but not HS68 fibroblast-conditioned medium. Breast cancer cells exhibit enhanced migration in co-culture with bone-derived cells but not HS68 fibroblasts or no co-cultured cells. Inhibition of Src kinase activity using the inhibitors PP2 or saracatinib or using siRNA abrogates the preferential migration of the breast cancer cell lines in response to bone-derived cells. Inhibition of Src activity with saracatinib does not have any significant effect on breast cancer cell invasion in the presence of bone-derived cells. Factors are identified that are produced preferentially by bone-derived cells over HS68 cells that may impact breast cancer cell behavior. This research implicates Src kinase as an important effector of bone-derived cell signals on breast cancer cell migration.     

第10号染色体上磷酸酶和张力蛋白同源缺失的基因对人卵巢癌A2780细胞侵袭和迁移能力的影响及相关机制

目的 探讨第10号染色体上磷酸酶和张力蛋白同源缺失的基因(PTEN)对人卵巢癌A2780细胞侵袭和迁移能力的影响及相关机制.方法 将携带外源性人PTEN基因的野生型质粒(WT-PTEN)和磷酸酶域突变型质粒(C124A-PTEN)转入人卵巢癌细胞株A2780中,利用Transwell小室法和划痕愈合实验检测转染前后细胞侵袭和迁移能力的变化,应用Western blot检测各组细胞PTEN及其下游相关蛋白表达的变化.以空载体质粒和未转染细胞作为对照.结果 细胞侵袭实验显示,WT-PTEN/A2780、C124A-PTEN/A2780、GFP/A2780和A2780细胞穿透Matrigel胶的细胞数,分别为(24.3±2.5)个、(43.7±3.8)个、(44.7±2.1)个和(45.0±3.0)个,WT-PTEN/A2780细胞的穿膜数明显少于其他各组(P＜0.05).划痕愈合实验显示,WT-PTEN/A2780、C124A-PTEN/A2780、GFP/A2780和A2780细胞的迁移距离分别为(54.1±3.7)μm、(78.7±3.4)μm、(78.1±3.1)μm和(76.8±3.5)μm,WT-PTEN/A2780细胞的迁移速度明显慢于C124A-PTEN/A2780、GFP/A2780和A2780细胞(P＜0.05).WT-PTEN/A2780细胞中基质金属蛋白酶9(MMP-9)蛋白的表达明显低于C124A-PTEN/A2780、GFP/A2780和A2780细胞(P＜0.05).结论 野生型PTEN可有效抑制A2780细胞的侵袭和迁移,该抑制作用与A2780细胞中MMP-9表达下调有关.

Abstract：

Objectiye To evaluate the effects of PTEN on invasive and migration ability of human ovarian cancer cell line A2780 and related mechanisms. Methods The plasmid including WT-PTEN and mutant PTEN were transferred into A2780 cells. The invasive and migration ability were measured before and after transfection by transwell chamber and wound-healing assays. The expression of PTEN protein and related proteins in the cells were detected by Western blot analysis. Empty plasmid-transfected A2780 and normal A2780 cells were used as control (the different four groups were named as WT-PTEN/A2780,C124A-PTEN/A2780, GFP/A2780 and A2780 ). Results The number of penetrating cells was significantly less in WT-PTEN/A2780 cells(24.3 ± 2.5 ) than those in C124A-PTEN/A2780, GFP/A2780 and A2780 cells (43.7 ± 3.8, 44.7 ± 2. 1 and 45.0 ± 3.0 ) ( P ＜ 0.05 ). The migration distance was markedly shorter in WT-PTEN/A2780 cells (54.1 ± 3.7) than those in C124A-PTEN/A2780, GFP/A2780 and A2780 cells (78.7 ± 3.4, 78.1 ± 3.1 and 76.8 ± 3.5 ) ( P ＜ 0. 05 ). Conclusions Transfection with PTEN may suppress the invasive and migration ability of ovarian cancer cell line A2780 depending on its phosphatase activity, and the suppressive effect may be due to the down-regulation of MMP-9 in the cancer cells.     

Effects of DNMT1 silencing on malignant phenotype and methylated gene expression in cervical cancer cells

Background

Both endoscopic and surgical approaches are employed in the treatment of early gastric cancer (EGC). The aim of this study was to establish appropriate treatment strategies for early gastric cancer.

Methods

We retrospectively examined clinicopathological data of EGC patients who had undergone surgery.

Results

A total of 327 patients (204 males and 123 females, mean age 63.2 years) were eligible for inclusion in the study. The median follow-up period was 31 months. Of 161 mucosal (pT1a) tumors, 87 were mainly undifferentiated and 110 had an undifferentiated component. Four patients with pT1a tumors had lymph node metastases; all these tumors were signet-ring cell carcinomas and were macroscopic type 0-IIc with ulceration, and only one of them had lymphatic invasion. Among patients with submucosal tumors, four of 43 patients with pT1b1 tumors and 37 of 123 patients with pT1b2 tumors had nodal metastases. Lymph node metastases were significantly higher in mixed undifferentiated type group than differentiated type group for both groups, pT1a-pT1b1 (p = 0.0251) and pT1b2 (p = 0.0430) subgroups. Only four of 45 patients with nodal metastases were diagnosed preoperatively by computed tomography (sensitivity 8.9%, specificity 96.2%). Nine patients with pT1b tumors had recurrence after surgery, and died. The sites of initial recurrence were liver, bone, peritoneum, distant nodes, and the surgical anastomosis.

Conclusions

The incidence of nodal metastases was approximately 5% in undifferentiated type mucosal (pT1a) tumors, and higher in submucosal (pT1b) tumors. The sensitivity of preoperative diagnosis of nodal metastases in EGC using computed tomography was relatively low in this study. Therefore at present surgery with adequate lymphadenectomy should be performed as curative treatment for undifferentiated type EGC.