Coexpression of EGFRvlll/ErbB2 in Human Breast Cancer

EGFRvIII/ErbB2 在人乳腺癌中的共表达

• 批准号: 6382732
• 负责人: Careen K Tang
• 金额: $ 25.76万
• 依托单位: GEORGETOWN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6382732
• 关键词: antitumor antibody; breast neoplasms; cell line; cell proliferation; epidermal growth factor; estrogen receptors; growth factor receptors; human tissue; immunocytochemistry; interleukin 3; metastasis; monoclonal antibody; neoplasm /cancer immunotherapy

DESCRIPTION: (Adapted from the investigator's abstract) EGFRvIII is a tumor specific, ligand-independent, constitutively active variant of the epidermal growth factor receptor. Our pilot results demonstrated that 70 percent (103/147) of invasive breast cancer express EGFRvIII. 86 percent (43/50) of ErbB-2 positive primary breast tumors were co-expressed with EGFRvIII. Even more striking was that 100 percent (4/4) of ErbB-2 positive metastatic lymph nodes co-overexpressed EGFRvIII. Transfection and expression of EGFRvIII in human breast cancer cell line (MCF-7) led to increase in colony formation and significantly enhanced tumorigenicity of MCF-7 cells in athymic nude mice. ErbB-2 phosphorylation was enhanced in EGFRvIII transfected MCF-7 cells. These results indicated that EGFRvIII could activate ErbB-2 kinase activity. In addition, despite the encouraging results from the advanced-disease trials with an anti-ErbB-2 antibody, Herceptin (rhuMAb HER2 or trastuzumab) clearly does not cure all tumors that overexpress ErbB-2. Based on these findings, we hypothesize that co-expression of EGFRvIII with ErbB-2 plays a critical role in human breast cancer progression. Co-expression of EGFRvIII with ErbB2 in breast cancer progression may influence Herceptin efficacy. Our ultimate goal is to develop diagnostic, prognostic, and predictive markers for Herceptin efficacy and responsiveness, as well as mechanistic rationale for novel therapeutic strategies. To achieve these goals, we propose studies with the following Specific Aims. 1): To elucidate the cross-talk between EGFRvIII with ErbB-2 and the biological effects of EGF-like ligands in a model system (32D cells): this involves generation of stable cell lines, which ectopically expresses EGFRvIII in pairwise combination with ErbB-2 in 32D cells. The biological effects of receptor cross-talk between the EGFRvIII and ErbB-2 receptor as well as ligand-induced proliferation will be investigated. 2): To determine the biological functional effects of co-expression of EGFRvIII in ErbB-2 overexpressing breast cancer cells: Non-tumorigenic, overexpressing ErbB-2 breast cancer cell lines will be transfected with EGFRvIII. The biological and biochemical effects on cell proliferation, tumorigenicity and metastatic potential in these transfectants will be defined in vitro and in vivo. 3): To determine whether co-expression of EGFRvIII modulates the Herceptin effect in ErbB-2 overexpressing cells: The impact of co-expression of EGFRvIII with ErbB-2 in Herceptin responsiveness will be evaluated by monitoring the inhibition of cell proliferation and tumorigenicity in three model systems (32D, N1H3T3 and EGFRvIII transfected overexpressing ErbB-2 breast cancer cell lines). 4): To validate the results from Aim 1 through Aim 3 in samples from breast cancer patients: Immunohistochemical analysis will be conducted to verify the frequency of EGFRvIII and co-expression with ErbB-2 with large cohorts of primary breast cancer specimens, metastatic lymph node specimens, as well as the clinical samples from patients in clinical trials with Herceptin. The correlation of their expression with other clinicopathological prognostic indicators in human breast cancer will be determined. These studies will provide us with new, important information relating the biological significance and functions of EGFRvIII co-expression of ErbB-2 in human breast cancer. Through these studies, we will gain valuable insights and identify potential markers, which may be good predictors for the efficacy of trastuzumab in treating ErbB-2-positive breast cancer patients. The results of the proposed studies may ultimately point to new directions of molecular therapies of breast cancer.

描述：(改编自研究人员摘要)EGFRvIII是一种肿瘤 特定的、不依赖于配体的、构成活性的表皮变异体 生长因子受体。我们的试点结果表明，70% (103/147)浸润性乳腺癌表达EGFRvIII。86%(43/50) ErbB-2阳性的原发乳腺肿瘤与EGFRvIII共表达。连 更引人注目的是，100%(4/4)的ErbB-2阳性转移淋巴 节点共表达EGFRvIII。EGFRvIII基因在真核细胞中的转染和表达 人乳腺癌细胞株(MCF-7)诱导集落形成增加 显著增强MCF-7细胞在裸鼠体内的致瘤性。 转EGFRvIII基因的MCF-7细胞中ErbB-2的磷酸化水平明显增强。这些 结果表明，EGFRvIII可激活ErbB-2激酶活性。在……里面 此外，尽管晚期疾病试验的结果令人鼓舞，但 抗ErbB-2抗体赫赛汀(rhuMAb HER2或曲妥珠单抗)明显起作用 不能治愈所有过度表达ErbB-2的肿瘤。基于这些发现，我们 假设EGFRvIII与ErbB-2共表达在 人类乳腺癌的进展。EGFRvIII与ErbB2在乳腺组织中的共表达 癌症进展可能会影响赫赛汀的疗效。我们的最终目标是 开发赫赛汀疗效的诊断、预后和预测标志物 和响应性，以及新疗法的机械原理 战略。为了实现这些目标，我们建议进行以下研究 明确的目标。1)：阐明EGFRvIII与ErbB-2和 EGF样配体在模型系统(32D细胞)中的生物学效应 涉及产生稳定的细胞系，该细胞系异位表达EGFRvIII 在32D细胞中与ErbB-2配对结合。细菌的生物学效应 EGFRvIII和ErbB-2受体之间的受体串扰以及 将对配体诱导的增殖进行研究。2)：确定 EGFRvIII在ErbB-2中共表达的生物学功能效应 过表达的乳腺癌细胞：不会致癌，过表达ErbB-2 将EGFRvIII基因导入乳腺癌细胞系。生物性和 生化对细胞增殖、致瘤性和转移的影响 这些转染体的潜力将在体外和体内确定。3)：至 确定EGFRvIII共表达是否调节Herceptin效应 ErbB-2过表达细胞：EGFRvIII与EGFRvIII共表达的影响 ErbB-2对赫赛汀的反应性将通过监测 三种模型系统对细胞增殖和致瘤性的抑制作用 (32D、N1H3T3和EGFRvIII转染过表达ErbB-2乳腺癌细胞 行)。4)：验证目标1至目标3的结果 乳腺癌患者：将进行免疫组织化学分析 验证EGFRvIII的表达频率并与ErbB-2和Large共表达 原发乳腺癌样本、转移性淋巴结样本、 以及赫赛汀临床试验患者的临床样本。 它们的表达与其他临床病理预后的关系 人类乳腺癌的指标将被确定。 这些研究将为我们提供有关 EGFRvIII共表达ErbB-2的生物学意义及作用 人类乳腺癌。通过这些研究，我们将获得宝贵的见解和 找出潜在的标记物，这些标记物可能会很好地预测 曲妥珠单抗治疗ErbB-2阳性乳腺癌结果是 拟议中的研究可能最终指向分子的新方向 乳腺癌的治疗方法。