不同转移能力的肺癌细胞系的形态结构与黏附分子表达的比较

肿瘤多细胞球体(multicellular tumor spheroid MTS)是应用组织培养方法使肿瘤细胞生长形成实体细胞团,被称为“肿瘤的体外模型”。细胞黏附分子(cell adhesion molecules,CAMs)是一类细胞膜受体分子(糖蛋白),它们在细胞生长、免疫反应及肿瘤转移等方面发挥重要的作用[1]。近年来,随着对肿瘤转移过程研究的深入,细胞黏附分子与癌转移的关系逐渐受到关注,本实验拟在将MTS用于黏附分子表达的研究以及CD44V6和CD29与肺癌转移关系方面进行探讨,从而为肺癌侵袭转移的研究及其临床治疗提供依据。1材料与方法1·1材料:人肺腺癌细胞系AGZY和…     

高低转移肺腺癌细胞系中肿瘤抑制基因p16、p21和p53表达研究

目的 探讨肿瘤抑制基因对肺腺癌细胞生长的抑制作用。方法 利用FuGene转染方式分别将p21和p16基因的表达质粒转入－对肺腺癌细胞系Anip973和AGZY83－a中,同时用含野生型p53 基因的腺病毒感染p16基因转染前后的这一对细胞系。对P16和P21蛋白过表达的细胞系进行了细胞生长曲线、克隆形成率、原位末端标记分析和流式细胞仪分析。结果 p16基因的过表达只能使细胞系的G1期细胞比例提高,但细胞生长曲线,克隆形成率均未出现改变,未检测到凋亡信号。P21蛋白过表达的一对细胞系细胞生长曲线斜率降低,克隆形成能力下降,并出现明显的G1期阻滞,但未检测到凋亡信号。p53基因感染AGZY83－a,Anip973及经过p16基因转染的细胞AGZY83－ap16和Anip973p16后呈现时间依赖性表达,细胞生长曲线和四唑盐比色法分析提高,野生型p53基因的大量表达明显抑制以上4种细胞的生长,Anip973和Anip973p16的生长抑制率高于AGZY83－a和AGZY83－ap16;Anip973p16和AGZY83-ap16的生长抑制率高于Anip973和AAGZY83－a。这4种细胞在感染p53后出现典型的凋亡信号。结论p16基因的过表达并不能抑制细胞系的生长,而p21基因的过表达通过G1期阻滞抑制这1对肺腺癌细胞的生长;野生型p53基因在AGZY83－a和Anip973中高效表达可产生明显的细胞生长抑制效应;野生型p53基因对肺腺癌高转移细胞系Anip973抑制作用更为明显。     

BRI基因在一对转移能力不同的肺腺癌细胞系中的序列分析与表达研究

目的 确认淀粉样纤维蛋白基因(amyloid fibrils，BRI)基因在l对同源但转移能力不同的肺腺癌细胞系AGZY83-a和Anip973中的序列并分析其表达。方法 采用测序技术，Northern印迹杂交。G显带后荧光原位杂交分析BRI基因在肺腺癌细胞系的序列与表达。结果 BRI基因在高转移肺腺癌细胞系Anip973中高表达，在其低转移母系AGZY83-a中低表达，两细胞系BRI基因染色体定位区均存在断裂重排。该基因染色体定位区在Anip973中出现扩增。已知BRI基因的-116bp～-5bp处碱基序列和-115bp～-5bp处碱基序列在AGZY83-a和Anip973中分别突变为CTCAGCAGCCCGC和TCAGCCGC。结论 BRI基因在转移能力不同的肺腺癌细胞系差异表达与该基因的染色体定位区域的断裂重排无关，与该基因染色体定位区拷贝数增加及5′非翻译区存在不同的突变可能相关。     

Ezrin在转移性骨肿瘤中的表达及其与CD44V6表达的相关性

目的探讨人体转移性骨肿瘤组织中Ezrin和CD44v6表达之间的关系及Ezrin mRNA的表达与转移性骨肿瘤临床病理特征的关系。方法收集28例转移性骨肿瘤和12例良性骨肿瘤,应用免疫组织化学技术检测Ezrin和CD44v6的蛋白表达,应用RT-PCR检测Ezrin mRNA的表达情况。结果转移性骨肿瘤中Ezrin、CD44v6的蛋白阳性表达显著高于它们在良性骨肿瘤中的阳性表达(P<0.05);Ezrin和CD44v6的表达呈正相关(r=0.053,P<0.05);Ezrin mRNA的阳性表达与患者性别、年龄、有无原发灶和转移瘤部位无关,但与其分化程度有关。结论 Ezrin可能参与了转移性骨肿瘤的浸润、转移;Ezrin发挥作用可能需要与细胞粘附分子CD44v6相互作用;检测Ezrin的表达可作为转移性骨肿瘤生物学行为的一项评估指标。     

COX-2抑制剂(NS-398)对结肠癌HT-29细胞体外侵袭力的作用及CD44v6、nm23-H1基因的调节

目的：研究NS-398对结肠癌HT-29细胞体外侵袭力的作用及CD44v6、nm23-H1基因的调节。 方法： 通过流式细胞仪检测COX-2和CD44v6的表达，MTT检测细胞活性，改良的Boyden小室法观察HT-29细胞侵袭重组基底膜的能力，RT-PCR观察nm23-H1 mRNA的表达。 结果： HT-29细胞COX-2表达阳性，0.1、1.0、10 μmol/L NS-398可显著抑制HT-29细胞侵袭重组基底膜的能力，且上述作用与NS-398的毒性作用无关。NS-398可下调CD44v6的表达，上调nm23-H1 mRNA的表达。 结论： NS-398具有抑制结肠癌细胞HT-29体外侵袭力的作用，下调CD44v6的表达和上调nm23-H1 mRNA的表达可能是其作用机制。     

CD44s和CD44v6在宫颈鳞癌中表达及其临床意义

目的：探讨宫颈鳞癌中CD44s和CD44v6的表达及其与临床病理资料的关系。方法：应用免疫组化EnVision两步法对31例宫颈鳞标本中CD44s和CD44v6蛋白表达并进行分析。结果：肿瘤原发灶中CD44s阳性表达率为61．3％（19／31）。CD44v6阳性表达率为93．5％（29／31）,CD44v6阳性率高于CD44s,CD44s阳性表达与临床分期,病理分级和分类无关（P＞0．05）,CD44v6阳性表达与肿瘤细胞分化程度无关,但与浸润程度及分期有关（P＜0．05）,结论：CD44v6基因蛋白与宫颈鳞癌的侵袭,转移相关,可作为预测肿瘤进展和预后的一种有用指标。     

非小细胞肺癌中CD44v6的表达

目的　探讨CD4 4v6表达与非小细胞肺癌临床病理特征之间的关系。方法　采用免疫组化S P法检测 132例非小细胞肺癌、6 6例淋巴结转移癌和 115例正常肺组织CD4 4v6表达的情况。结果　非小细胞肺癌CD4 4v6阳性表达率为4 8 4 8% ,高于正常肺组织 17 39%的阳性表达率。CD4 4v6阳性表达与淋巴结转移状况、TNM分期、肿瘤大小和组织学类型有相关性。非小细胞肺癌淋巴结转移组、TNMⅢ期患者、直径 >3cm的肿瘤和鳞癌CD4 4v6阳性表达率分别高于无淋巴结转移组、TNMⅠ期和Ⅱ期患者、直径≤ 3cm的肿瘤和腺癌。淋巴结转移癌CD4 4v6阳性表达率高于肺原发癌。CD4 4v6阳性表达与患者的性别、年龄和组织学分级无相关性。结论　CD4 4v6阳性表达预示非小细胞肺癌具有较强的侵袭和转移能力 ,可作为一项预测非小细胞肺癌转移潜能生物学指标。     

非小细胞肺癌中Ezrin和CD44v6的表达及意义

目的 探讨非小细胞肺癌中Ezrin和CD44v6的表达及其与肺癌各种临床病理参数之间的关系.方法 采用免疫组化SP法检测55例非小细胞肺癌组织中Ezrin及CD44v6的表达.结果 Ezrin的表达程度与非小细胞肺癌的TNM分期(P=0.004)和淋巴结转移(P=0.003)密切相关; CD44v6的表达程度与非小细胞肺癌的TNM分期(P=0.012)和淋巴结转移(P=0.010)密切相关;Ezrin 和CD44v6两者在非小细胞肺癌组织中的表达呈正相关(r=0.568, P=0.000).结论 Ezrin和CD44v6与肺癌淋巴结转移和临床TNM分期密切相关,联合检测Ezrin和CD44v6有助于判断肺癌的预后.     

乳腺浸润性导管癌中CD44v6的表达及其预后分析

乳腺癌是女性最常见的恶性肿瘤之一,严重威胁着妇女的身心健康.细胞黏附分子CD44v6是近年来研究较多的一类黏附分子,是分布极为广泛的一组细胞表面跨膜糖蛋白,参与细胞与细胞、细胞与间质之间的特异性黏接,与乳腺癌的发生、发展、浸润、转移密切相关.本实验应用组织芯片技术和免疫组化方法检测乳腺浸润性导管癌组织中CD44v6的表达情况,并探讨CD44v6在乳腺浸润性导管癌的表达及其临床、预后意义.     

TTF-1在肺腺癌中的表达及其诊断意义

目的：评价甲状腺转录因子－1（TTF－1）在鉴别肺原发性腺癌与转移性腺癌中的临床病理应用价值。方法：20例肺原发性腺癌：10例高分化，包括3例乳头状、3例腺泡状、3例混合型腺癌和1例细支气管肺泡癌；10例低分化，包括4例黏液腺癌（其中1例为印戒细胞癌）和6例混合型腺癌。另选20例的胃肠道及卵巢腺癌，免疫组化应用TTF－1抗体。结果：95％的肺原发性腺癌表达TTF－1，而胃肠道及卵巢腺癌完全不表达。结论：对于确定肺原发或转移性腺癌的病理诊断。TTF－1是一个有用的特异性抗体，特别是在体积较小的肺活检标本或原发灶不明而仅有肺内转移时。     

Inhibition of Cyclooxygenase‐2 Suppresses Lymph Node Metastasis via VEGF‐C

Most experimental work addressing cyclooxygenase‐2 (COX‐2) inhibitor has focused on suppressing hematogenic spread. Little is known about the mechanism by which this inhibitor can also block lymphatic metastasis. Here, the effects of COX‐2 inhibitor on vascular endothelial growth factor‐C (VEGF‐C) expression, lymphangiogenesis and lymph node metastasis were investigated. Utilizing the highly metastatic human lung adenocarcinoma cell line Anip973 and its parental line AGZY83‐a, which has a low metastatic capacity, we found elevated VEGF‐C and COX‐2 immunoreactivity in Anip973 cells compared with AGZY83‐a cells. Celecoxib down‐regulated expression of VEGF‐C mRNA and protein in Anip973 cells while PGE₂ up‐regulated expression of VEGF‐C mRNA and protein in AGZY83‐a cells in a concentration‐dependent manner. The expression of COX‐2 and VEGF‐C was significantly increased in xenografted Anip973 tumors compared with AGZY83‐a tumors. The Anip973 tumors showed more lymphatic vessels and lymph node metastasis than the AGZY83‐a tumors. In vivo, celecoxib decreased VEGF‐C expression in Anip973 tumor‐treated mice to a similar level to that in the AGZY83‐a tumor‐treated mice. Consistent with this decrease in VEGF‐C expression, the density of lymphatic vessels and lymph node metastasis in Anip973 tumor‐treated mice were suppressed to approximately that found in the AGZY83‐a tumor‐treated ones. Taken together, our results suggest that the differential expression of COX‐2 and VEGF‐C might help explain the different metastasis phenotype of lung adenocarcinoma cancer, and that COX‐2 inhibitor mediates VEGF‐C to block lymphangiogenesis and lymph node metastasis. Thus, COX‐2 may be a potential therapeutic target for blocking lymph node metastasis in lung adenocarcinoma. Anat Rec, 2009. © 2009 Wiley‐Liss, Inc.     

应用mRNA差异显示技术克隆人肺腺癌转移相关基因

肿瘤转移是恶性肿瘤最基本的生物学特征。为了探讨恶性肿瘤的侵袭和转移的机理，选择两株具有相同的细胞来源、但具有不同转移能力的人肺腺癌细胞系ＡＧＺＹ８３ａ和Ａｎｉｐ９７３作为研究材料，采用ｍＲＮＡ差异显示（ｍＲＮＡｄｉｆｅｒｅｎｔｉａｌｄｉｓｐｌａｙ）技术，对这两个细胞系的基因表达差异情况进行了分析。结果显示，在这两个细胞系之间存在明显的基因表达差异，说明在低转移的ＡＧＺＹ８３ａ向高转移的Ａｎｉｐ９７３演变过程中涉及多个基因的激活与失活。研究结果还提示，在高转移的Ａｎｉｐ９７３细胞系中，某些基因的表达或高表达与人类逆转录病毒基因ＬＴＲ的整合有关。另一个克隆与人类线粒体基因ＮＤ４具有高度同源性，其高度表达与Ａｎｉｐ９７３的转移表型有关。表明肿瘤的转移是一个多基因参与的过程，由于这些基因的相互作用及细胞内外环境因素的影响，最终决定了肿瘤细胞的转移表型。     

Differential expression of RAB5A in human lung adenocarcinoma cells with different metastasis potential

For the sake of better understanding the molecular mechanism of neoplasia, we have used the mRNA differential display technique to analyze two human lung adenocarcinoma cell lines, AGZY83-a and Anip973. Anip973 was isolated from AGZY83-a, but manifested much higher metastatic potential than the parent line. We found that a significant differential cDNA fragment in Anip973 was over-expressed, then over-expressed cDNA fragment was cloned and sequenced. It showed that the over-expressed cDNA in Anip973 was RAB5A cDNA. And the RAB5A cDNA sequence was corresponding between the two cells. To determine whether RAB5A may be differentially expressed in the two human lung adenocarcinoma cells at protein level, we further detected RAB5A protein in the two cells by using immunofluorescent method. RAB5A protein was upregulated in highly metastatic Anip973. We also detected the difference in RAB5A gene expression at RNA level in human non-small cell lung carcinoma by RT-PCR. Using immunohistochemical staining, we also examined RAB5A change at protein level in 45 cases human non-small cell lung carcinoma paraffin sections. The results proved the evidence of upregulation of RAB5A in malignant tumor, indicated over-expression of RAB5A gene was correlated with the malignant degree and metastatic potential of lung cancer(² test, p <0.01). The RAB5A gene is a member of RAS superfamily, which can transcribe GTP-binding protein that plays an important role in signal transduction of protein trafficking at the cell surface and GDP/GTP cycle in the regulation of endocytotic membrane traffic. Thus our results indicated that over-expression of the RAB5A gene was involved in the process of transformation from AGZY83-a to the higher metastatic cell line Anip973. The result may be a powerful experimental evidence that over-expression of RAB5A gene associated with neoplasia metastasis.     

CD44和CD44v6基因在胃腺癌组织中的表达及其意义

目的： 研究胃腺癌组织中ＣＤ４４ 的表达及其与淋巴结转移和预后的关系。方法： 应用免疫组化方法, 对１０５ 例胃腺癌组织中ＣＤ４４ 的表达进行了观察, 并对其中６２ 例患者做了随访。结果： ＣＤ４４ 和ＣＤ４４ｖ６ 基因的表达率分别为５４－３ ％ 和４８－６ ％ 。ＣＤ４４ｖ６ 在胃腺癌组织中的表达与癌细胞的分化、浸润深度, 以及临床分期和预后有关（Ｐ＜ ０－０５）, 而ＣＤ４４ 的表达则与上述临床病理指标无关。另外, 抗ＣＤ４４ 和抗ＣＤ４４ｖ６ 抗体的阳性反应, 与癌细胞的淋巴结转移有关（ＣＤ４４ｖ６, Ｐ＜ ０－０１ ; ＣＤ４４ , Ｐ＜ ０－０５） 。结论： ＣＤ４４ 的表达可用于胃癌患者的病情监测, 其中ＣＤ４４ｖ６ 有望作为判断预后的一个指标。     

CD44 exon variant 6 epitope and hyaluronate synthase are expressed on HT29 human colorectal carcinoma cells in a SCID mouse model of metastasis formation

The factors which lead to the formation of metastases are generally poorly understood; however the expression of a particular variant of the cell adhesion molecule CD44 may be important in facilitating metastasis formation in colon cancer. The aim of the present study was to investigate the expression of CD44 exon v 6 (CD44v6), hyaluronate (one of its ligands), and hyaluronate synthase, in a clinically relevant animal model of metastatic colon carcinoma. HT29 human colon carcinoma cells were injected subcutaneously between the scapulae of severe combined immunodeficient (SCID) mice and left for 3 weeks (by which time the tumours had produced metastases in the lungs). Morphological observations at the tumour-host interface were consistent with the dissociation of neoplastic cells from the primary tumours, and the ability of these cells to migrate through the extracellular matrix facilitating metastasis formation. Immunohistochemically detectable hyaluronate synthase expression was increased in vivo compared with the parent cell line in vitro. CD44v6 expression and hyaluronate were increased around single cells at the periphery of tumours compared with the central regions. CD44v6 and hyaluronate synthase expression were co-expressed in the same cells. Indeed, the present study is the first to demonstrate hyaluronate synthase expression by an epithelial cell type.     

COX‐2‐Mediated Regulation of VEGF‐C in Association With Lymphangiogenesis and Lymph Node Metastasis in Lung Cancer

The mechanisms underlying the effects of COX‐2 on tumor lymphangiogenesis remain largely undefined. Here, the human lung cancer cell lines A549, 95D, Anip973, and AGZY83‐a with different metastatic capacities were investigated by immunostaining, western blotting, and real‐time RT‐PCR. We observed increased expressions of COX‐2 and VEGF‐C in the three highly metastatic cell lines compared with the less metastatic AGZY83‐a cell line. The COX‐2‐specific inhibitor Celecoxib suppressed VEGF‐C expression whereas the main COX‐2 metabolite PGE₂ elevated VEGF‐C expression in Anip973 and AGZY83‐a cells in positive and negative experiments. To determine the functional link to COX‐2 more specifically and elucidate the mechanistic pathway, we used a siRNA to knock down the high COX‐2 expression in Anip973 cells and transfected a COX‐2 cDNA to enhance the low COX‐2 expression in AGZY83‐a cells, and then treated the cells with EP1/EP4 agonists or antagonists, respectively. The results revealed that the EP1/EP4 agonists significantly increased VEGF‐C production in the COX‐2‐knockdown Anip973 cells. In contrast, the EP1/EP4 antagonists diminished VEGF‐C production in the COX‐2‐overexpressing AGZY83‐a cells. Furthermore, animal models provided evidence that Celecoxib decreased VEGF‐C expression, lymphangiogenesis, and lymph node metastases in Anip973 cells, whereas PGE₂ treatment increased the same factors in the parental AGZY83‐a cells. A positive correlation between COX‐2 and VEGF‐C was also confirmed in vivo. The present data suggest that COX‐2 regulates VEGF‐C expression via the PGE₂ pathway, and that EP1/EP4 receptors are involved in PGE₂‐mediated VEGF‐C production. Thus, COX‐2 may represent a candidate gene for blocking tumor lymphangiogenesis and lymph node metastasis. Anat Rec, 2010. © 2010 Wiley‐Liss, Inc.     

Epithelial hyaluronic acid and CD44v6 are mutually involved in invasion of colorectal adenocarcinomas and linked to patient prognosis

Desmoplastic stroma of colorectal adenocarcinomas contains a variety of extracellular matrix molecules, including hyaluronic acid (HA). Overexpression of the HA receptor CD44 and, in particular, its splicing variant CD44v6 has been described as a prognostic factor for patients with colorectal adenocarcinomas in some studies, but converse reports also exist. Our hypothesis is that these divergent results may be related to the fact that the function of CD44v6 depends on the HA content of cell-surrounding matrix. Therefore, we studied the expression of HA and CD44v6 in tissue samples of 145 patients suffering from colorectal adenocarcinomas using immunohistochemistry. Expression of HA was separately evaluated in tumor epithelium and stroma. We additionally examined the influence of HA on invasion and adhesion of colorectal adenocarcinoma cells in vitro. The results show that epithelial HA expression was not correlated with tumor stage but with lymph-node or distant metastasis. Patients with tumors expressing epithelial HA had a decreased overall survival (P=0.017) as well as tumors with coexpression of epithelial HA and CD44v6 (P=0.011). The latter issue remained an independent prognostic factor in multivariate analysis (relative risk 5.06; 95% confidence interval, 1.18–21.57; P=0.028). HA exclusively stimulated in vitro invasion of CD44v6-expressing cells. This stimulation was partly reversed by an anti-CD44v6 antibody. Our findings suggest that the adverse prognostic effect of CD44v6 in colorectal adenocarcinoma might be restricted to those tumors that have pericellular HA.     

Differential expression of CD44v6 in adenocarcinoma of the pancreas: an immunohistochemical study

Alternative splicing gives rise to numerous CD44 isoforms, some of which seem to have a role in tumour metastasis. Specifically, a variant form of CD44 with sequences encoded by exon v6 (CD44v6) confers metastatic potential when transfected into a nonmetastasizing cell line of rat pancreatic adenocarcinoma. This study has investigated standard CD44 (CD44s) and CD44v6 expression immunohistochemically in 6 samples of normal pancreatic tissue, 4 of tissue affected by chronic pancreatitis, and 24 of tissue from metastasizing and nonmetastasizing pancreatic adenocarcinomas. In addition, 18 samples from lymph node or visceral metastases were included in the study. CD44s was expressed in nonneoplastic tissue and in tissue from pancreatic adenocarcinomas. In contrast, CD44v6 was not detected in any of the normal tissue or chronic pancreatitis specimens, whereas 54% of pancreatic adenocarcinomas and 55% of metastases expressed this variant exon. Although it is not clear whether CD44 isoforms containing exon v6 play a part in malignant progression in the human exocrine pancreas, it seems plausible that the expression of multiple isoforms containing this and other variant exon confers a selective advantage on pancreatic adenocarcinoma.