【作者】 王万里；

【导师】 李怀斌；

【作者基本信息】 郑州大学 ， 消化内科， 2004， 硕士

【摘要】 大肠癌包括结肠癌和直肠癌，是常见的恶性肿瘤。近20年来，我国该病发病率上升趋势十分明显。大肠癌的发生、发展及转移是一个多因素、多阶段的复杂过程，涉及到癌基因的激活、抑癌基因的失活、细胞黏附的改变及蛋白酶活性改变等多个环节。 上皮钙黏附素(E-cadherin，E-cad．)是一种跨膜糖蛋白分子，通过钙依赖的同种亲和性细胞-细胞间的黏附参与建立和维持细胞间的连接，在E-cadherin介导的细胞-细胞间黏附中，E-cadherin起着细胞黏附的拉链作用。β-连环素(β-catenin，β-cat．)在胞膜与E-cad．结合成复合体，该复合体通过α-catenin与细胞骨架的肌动蛋白微丝网连接。E-cad．-cat复合体介导同型细胞-细胞黏附，已知在胚胎发育、上皮细胞表型形成和维持中发挥重要作用。任何破坏细胞内该复合体的因素也将使细胞黏附功能丧失。许多临床和实验研究发现E-cad．的黏附功能在人类大多数上皮细胞癌中常常丢失，包括大肠癌、乳腺癌、前列腺癌等。大肠腺瘤中β-cat．可异位表达于胞浆和／或胞核，并与核内TCF／LEF家族成员结合启动一些基因转录，参与大肠癌发生。 黏着斑激酶(focal adhesion kinase，FAK)是Schaller等发现的能被scr内源性蛋白酪氨酸激酶激活的主要底物，属于非受体蛋白酪氨酸激酶，具有调节细胞发育、生长、存活和凋亡，调节细胞与ECM(细胞外基质)黏附的功能。FAK通过与焦点黏附物结合，在整和素介导的细胞与ECM黏附中发挥重要作用。FAK活性与其酪氨酸磷酸化水平密切相关。结肠癌中FAK酪氨酸磷酸化水平升高，活性增强。本研究旨在探讨E-cad．、β-cat．、FAK在不同大肠黏膜的表达以及它们的表达与大肠癌各种临床病理因素之间的关系，为大肠癌的早期诊断、治疗及预后判断提供理论依据。郑州大学2004年硕士毕业论文上皮钙薪附素、p一连环素、勃着斑激酶在大肠癌的表达及临床意义 材料和方法:(1)49例癌组织标本来源于2 003年1月一2003年10月河南省人民医院、河南省肿瘤医院普外科手术切除的标本和郑州大学一附院1999年3 月一1999年7月普外科手术切除的标本。12例正常大肠豁膜、28例大肠腺瘤(均 为轻中度不典型增生)来自2003年河南省人民医院内镜室镜下切除的标本，所有病例均经手术和病理证实。2003年标本经4%多聚甲醛(含有0.1%DEPC)液固定，1999标本经10%中性福尔马林固定，常规脱水后石蜡包埋。(2)采用免疫组化SP (链霉卵白素一过氧化物酶法)法检测E一cad.、p一cat.、FAK在不同大肠勃膜的表达情况。(3)统计工具采用SPSS10.O版软件。样本率比较采用x，检验和四格表精确概率法，相关分析采用Spearman相关分析，对实验分组资料以a=0 .05作为检验水准。 结果:1.E一cad.在正常大肠豁膜上皮细胞和大肠腺瘤细胞呈胞膜阳性表达，仅有少数细胞膜表达缺失。大肠癌E一cad.膜表达明显缺失，缺失率为57.1%，与前两组比较差异有显著性(只0.01)。p一cat.在正常大肠豁膜上皮细胞和大肠腺瘤细胞呈胞膜阳性表达，仅有少数膜表达缺失。大肠癌p一cat.膜表达明显缺失，缺失率为67.3%，与前两组比较差异有显著性(只0.01)。大肠腺瘤、腺癌p一cat.呈胞浆和/或胞核异位表达，大肠腺瘤p一cat.异位表达率35.7%，高于正常勃膜组(只0.05)。大肠癌p一cat.异位表达率61.2%，显著高于大肠腺瘤组(只0.05)。队K在多数正常大肠勃膜上皮细胞呈胞浆阴性表达，少数呈胞浆弱阳性表达。大肠腺瘤FAK胞浆阳性表达率39.3%，与正常大肠豁膜组比较差异无显著性(乃0.05)。大肠癌FAK胞浆阳性表达率65.3%，与前两组比较差异有显著性(只0.01)。 2.E一cad.膜表达缺失率在大肠癌结肠组为50.0%，直肠组为62.IW0，两组相比差异无显著性(乃0.05)。在不同浸润深度的大肠癌标本中，E一cad.膜表达缺失率在未超过深肌层组为46.2%，在超过深肌层组为61.1%，两组相比差异无显著性(乃0.05)。E一cad.膜表达缺失率在大肠癌高、中、低不同分化组分别为68.4%、62.5%、35.7%，三组相比差异无显著性(乃0.05)。E一cad.膜表达缺失率在大肠癌有淋巴结转移组为84.20k，在无淋巴结转移组为40.0%，两组相比差异有显著性(只0.01)。在大肠癌不同DukeS分期的标本中，E一cad.膜表达缺失率在AB期组为40.0%，CD期组为84.2%，两组相比差异有显著性(只0.01)。郑州大学2004年硕士毕业论文上皮钙勃附素、日一连环素、勃着斑激酶在大肠癌的表达及临床意义 3.p一cat.异位表达率在大肠癌结肠组为60.0%，直肠组为62.1%，两组相比差异无显著性(乃0.05)。在不同浸润深度的大肠癌标本中，p一cat.异位表达率在未超过深肌层组为30.8%，在超过深肌层组为72.2%，两组相比差异有显著性(只0.05)。D一cat.异位表达率在高、中、低不同分化组分别为57.9%、75.0%、50.0%，三组相比差异无显著性(乃0.05)。p一cat.异位表达率在有淋巴结转移组为89.5%，在无淋巴结转移组为42.3%，两组相比差异有显著性(只0.01)。在大肠癌不同Dukes分期的标本中，B一cat.异位表达率在AB期组为42.3%，CD期组为89.5%，两组相比差异有显著性(只0.01)。 4.p一cat.膜表达缺失率在大肠癌结肠组为70.5%，直肠?更多还原

【Abstract】 Colorectal cancer is a kind of common and malignant tumor. The incidence of this disease has been increasing significantly in recent 20 years in China. The tumorigenesis and metastasis of colorectal cancer is a complicated process with many steps concerning the activation of oncogenes, inactivation of anti-oncogenes, the changing of adhesion among cells and the changing of activation of enzymes etc.E-cadherin (E-cad.) is a kind of crossing-membrace glucoprotein molecule, which, dependenting on calcium, establishes and holds homotypic cell adhesion and it is a kind of sliding fastener among homotypic cells. β-catenin( B -cat.) linked to E-cad.on cell membrace comes into being a kind of complex, which links to the actin in the cell framework through a-catenin.It is known that the homotypic cell adhesion, depending on the E-cad./ β-cat complex, plays an important role in the forming and maintaining of epithelial style.The factors which destroy this complex will breakdown the homotypic cell adhesion .Many clinic studies and experiments show that function of E-cad. always drops in most of cancers including colorectal cancer,breast cancer,prostate cancer etc. The cytoplasmic and /or nuclear expression of β-catenin may appear in the colorectal adenoma. β-cat. can link to the members of TCF/LEF family and stamp the transcription of some genes,which contributes to the tumorigenesis of colorectum.FAK(focal adhesion kinase) discovered by Schaller is a major substance which can be activated by src-ingeneration protein-tyrosine kinase and it is a non-receptorprotein-tyrosion kinase.It can regulate the developing, keeping alive, apoptosis of cells and adhesion between cells and ECM.It plays a role in the integrin-mediated signal transduction pathway through linking to the Focal Adhesion Foci.The activation of FAK is closely associated with its phosphptyrosine content and increases with its enhanced level of phosphotyrosine in colorectal cancer.The aim of this study is ,through evaluating the expression of E-cad., β-cat. and FAK in different colorectal mucosa and the relationship between their expression and clinicopathologocal factors,to provide theoretical basis for early diagnosis,therapy and prognosis of colorectal cancer.Materials and Methods:(1)49 surgically resected colorectal cancer samples,12 normal colorectal mucosa samples and 28 endoscopic resected colorectal adenoma samples with mild to moderate displasia were all confirmed pathologically. The samples in 2003 were fixed in 4% Polyoxymethylene/ 0.1M PBS (0.1%DEPC), and the rest were fixed in 10% neutral formalin. All the samples were embedded in paraffin. (2)SP immunohistochemistry technique was used to detect the expression of E-cad., β-cat. and FAK in the different colorectal mucosa.(3) The data was analysed by software SPSS 10.0. x2-test and spearman correlation were used to compare difference between groups, a =0.05 was considered as statistically significant value.Results: (1) The membranous expression of E-cad. appeared in most of nomal colorectal mucosa and colorectal adenoma.The reduced membranous expression of E-cad.appeared in a majority of colorectal cancer.The reduced membranous expression rate of E-cad. was 57.1% in colorectal cancer,which was significantly higher than the last two groups(P<0.01). The reduced membranous expression rate of 3 -cat. was 67.3% in colorectal cancer, which was significantly higher than the last two groups(P<0.01).The cytoplasmic and/or nuclear expression of β-catenin was found in the colorectal adenoma and cancer.The rate of the cytoplasmic and /or nuclear expression of β-catenin was 61.2% in coloretal cancer,which was significantly higher than that in colorectal adenoma(35.7%, P<0.05). Moreover, the rate of cytoplasmic and /or nuclear expression of β-catenin in colorectal adenomawas significantly higher than that in normal colorectal epithelium. FAK was expressed in cytoplasm.The rate of FAK expression was 65.3% in colorectal cancer, which was significantly higher than that in the colorectal adenoma更多还原