OVARIAN CARCINOMA--ROLE OF LAMININ AND ITS RECEPTORS

恶性卵巢癌患者预后差 可能是由于他们的肿瘤本身更具侵略性 与良性或交界性囊腺瘤患者相比， 有更好的预后。 原癌基因c-erb-B2已被证明 在原发性上皮性卵巢肿瘤中扩增， 已经显示了基因扩增，癌基因表达， 降低卵巢癌患者的存活率。 的组件 基底膜（BM）和细胞外基质（ECM 各种细胞生长、发育和分化的调节剂 类型 BM和ECM蛋白在调节表型中的作用 卵巢癌细胞的行为尚未得到彻底研究 而且人们对此知之甚少。 层粘连蛋白是主要的非胶原性糖蛋白 的BM，已被证明可以促进粘合，铺展， 多种肿瘤细胞类型的体外迁移。 初步 研究中，我们观察到正常人卵巢上皮细胞 粘附于层粘连蛋白和层粘连蛋白的较小片段。 有趣的是， 卵巢癌细胞系和这些卵巢癌细胞系的转染子 含有c-erb表达增加的癌细胞系， B2基因产物粘附于层粘连蛋白的不同片段;这表明， 卵巢癌细胞可能具有不同的受体， 层粘连蛋白的结构域。 这些初步意见可以提供一个 卵巢上皮细胞异常行为的解释 癌细胞，因为它们不再以正常的方式粘附在细胞表面。 相反，它们从BM释放，播种其他位点，发展成一个 腹水形成或侵入卵巢间质。 假设， 恶性卵巢癌的侵袭性越强， 癌细胞与正常卵巢上皮细胞相比， 改变细胞对层粘连蛋白的反应，可能是由于 层粘连蛋白受体的改变。 为了验证这一假设， 确定层粘连蛋白是否含有促进差异表达的序列， 正常卵巢的粘连、扩散、迁移和/或侵袭 上皮细胞与恶性卵巢上皮癌的比较 细胞 然后，将在 层粘连蛋白和层粘连蛋白序列，以及c-erb- B2细胞 此外，细胞表面受体，特别是， 整合素亚单位，这些卵巢细胞用来与层粘连蛋白相互作用 层粘连蛋白的特定序列将被鉴定;这可能是 对卵巢的分化和迁移很重要 癌细胞 最后，将体外试验与 通过免疫化学定位层粘连蛋白和 正常卵巢上皮组织切片中的层粘连蛋白受体，良性 浆液性囊腺瘤、交界性浆液性囊腺瘤和恶性 卵巢腺癌 相关性将在 免疫组化染色模式，肿瘤的分期， c-erb-B2水平 这些研究表明， 了解调节表型行为的分子机制 卵巢癌细胞，并可能有助于设计 用于治疗卵巢癌的生物药物。

Malignant ovarian carcinoma seen in patients who have a poor prognosis may be due to the inherently more aggressive behavior of their tumor cells compared to patients with benign or borderline cystadenomas, who have a much better prognosis. The proto-oncogene c-erb-B2 has been shown to be amplified in primary epithelial ovarian tumors, and some studies have shown a correlation between gene amplification, oncogene expression, and decreased survival in patients with ovarian cancer. Components of the basement membrane (BM) and extracellular matrix (ECM) are important modulators of growth, development, and differentiation for various cell types. The role of BM and ECM proteins in modulating the phenotypic behavior of ovarian carcinoma cells has not been thoroughly investigated and is poorly understood. Laminin, the major noncollagenous glycoprotein of the BM, has been shown to promote the adhesion, spreading, and migration of a variety of tumor cell types in vitro. In preliminary studies, we have observed that normal human ovarian epithelial cells adhere to laminin and to smaller fragments of laminin. Interestingly, ovarian carcinoma cell lines and transfectants of these ovarian carcinomas cell lines that contain an increased expression of the c-erb- B2 gene product adhere to different fragments of laminin; suggesting that ovarian carcinoma cells may have altered receptor(s) for the various domains of laminin. These preliminary observations may provide an explanation as to the abnormal behavior of the ovarian epithelial carcinoma cells, since they no longer adhere in a normal fashion to the BM; rather, they release from the BM, seed other sites, develop into an ascites form, or invade into the stroma of the ovary. The hypothesis to be tested is that the more aggressive behavior of the malignant ovarian carcinoma cells, compared to normal ovarian epithelial cells, is related to an altered cellular response towards laminin, perhaps due to alterations in laminin receptors. To test this hypothesis, it will be determined whether laminin contains sequences that promote differential adhesion, spreading, migration, and/or invasion of normal ovarian epithelial cells compared to malignant ovarian epithelial carcinoma cells. Correlations will then be made between the behavior of the various cells on laminin and laminin sequences, and the levels of c-erb- B2 in the cells. In addition, the cell surface receptors, in particular, integrin subunits, that these ovarian cells use to interact with laminin and specific sequences of laminin will be identified; this may be important for the differential adhesiveness and migration of ovarian carcinoma cells. Finally, the in vitro assays will be compared to what is observed in vivo, by immunohistochemically localizing laminin and laminin receptors in tissue sections of normal ovarian epithelium, benign serous cystadenomas, borderline serous cystadenomas, and malignant ovarian adenocarcinomas. Correlations will be made between the immunohistochemical staining patterns, the staging of the tumors, and the levels of c-erb-B2. These studies represent an approach towards understanding the molecular mechanisms modulating the phenotypic behavior of ovarian carcinoma cells and potentially aid in designing biopharmaceuticals for therapeutic use in ovarian cancer.