Coexpression of EGFRvlll/ErbB2 in Human Breast Cancer

EGFRvIII/ErbB2 在人乳腺癌中的共表达

• 批准号: 6789937
• 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/6789937
• 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：（改编自研究者摘要）EGFRvIII是一种肿瘤 特异性、配体非依赖性、组成型活性的表皮细胞变体 生长因子受体我们的试点结果表明， (103/147）浸润性乳腺癌表达EGFRvIII。86%（43/50）的 ErbB-2阳性原发性乳腺肿瘤与EGFRvIII共表达。甚至 ErbB-2阳性淋巴结转移率为100%（4/4）， 淋巴结共过表达EGFRvIII。EGFRvIII的转染和表达 人乳腺癌细胞系（MCF-7）导致集落形成增加， 显著增强MCF-7细胞在裸鼠体内的致瘤性。 在EGFRvIII转染的MCF-7细胞中ErbB-2磷酸化增强。这些 结果表明，EGFRvIII可激活ErbB-2激酶活性。在 此外，尽管晚期疾病试验的结果令人鼓舞， 抗ErbB-2抗体赫赛汀（rhuMAb HER 2或曲妥珠单抗） 并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 人乳腺癌进展。EGFRvIII与ErbB 2在乳腺中的共表达 癌症进展可能影响赫赛汀的疗效。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 和反应性，以及新的治疗机制的基本原理， 战略布局为了实现这些目标，我们建议进行以下研究 具体目标。1）：为了阐明EGFRvIII与ErbB-2之间的串扰， EGF样配体在模型系统（32 D细胞）中的生物学效应： 涉及异位表达EGFRvIII的稳定细胞系的产生 在32 D细胞中与ErbB-2成对组合。的生物学效应 EGFRvIII和ErbB-2受体之间的受体串扰，以及 将研究配体诱导的增殖。（2）确定 在ErbB-2中共表达EGFRvIII的生物学功能效应 过表达乳腺癌细胞：非致瘤性，过表达ErbB-2 乳腺癌细胞系将用EGFRvIII转染。生物和 对细胞增殖、致瘤性和转移性的生物化学作用 将在体外和体内确定这些转染子的潜力。3）：至 确定EGFRvIII的共表达是否调节了赫赛汀的作用， ErbB-2过表达细胞：EGFRvIII与ErbB-2共表达的影响 将通过监测ErbB-2在赫赛汀中的反应性， 在三种模型系统中抑制细胞增殖和致瘤性 (32D、N1 H3 T3和EGFRvIII转染过表达ErbB-2乳腺癌细胞 线）。4）：验证目标1至目标3的样品结果， 乳腺癌患者：将进行免疫组织化学分析， 验证EGFRvIII的频率以及与ErbB-2的共表达， 原发性乳腺癌样本、转移性淋巴结样本， 以及来自赫赛汀临床试验中患者的临床样品。 它们的表达与其他临床病理预后的相关性 将确定人类乳腺癌的指标。 这些研究将为我们提供新的重要信息， EGFRvIII与ErbB-2共表达的生物学意义和功能 人类乳腺癌通过这些研究，我们将获得宝贵的见解， 确定潜在的标志物，这可能是疗效的良好预测因子， 曲妥珠单抗治疗ErbB-2阳性乳腺癌患者。的结果 所提出的研究可能最终指向分子生物学的新方向。 乳腺癌的治疗