c Src and EGF Receptor in Breast Cancer Development

c Src 和 EGF 受体在乳腺癌发展中的作用

• 批准号: 6690649
• 负责人: SARAH J PARSONS
• 金额: $ 0.39万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-01 至 2007-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6690649
• 关键词: athymic mouse; breast neoplasms; epidermal growth factor; genetically modified animals; growth factor receptors; neoplastic growth; oncoproteins; phosphoproteins; phosphorylation; protein structure function; protooncogene; tissue /cell culture

DESCRIPTION (provided by applicant): Members of the epidermal growth factor receptor (EGFR) and c-Src tyrosine kinase families are frequently co-overexpressed in human neoplasias. This co-overexpression suggests that members of the two families may functionally interact to affect tumor formation and/or progression. Results from recent studies in both a model fibroblast system and in human breast cancer cell lines and tumor tissues have indicated that c-Src and EGFR synergistically interact to promote tumor formation. Evidence also supports a functional interaction between c-Src and two other members of the EGFR family, HER2 and HER3. The potentiation of EGFR-mediated tumor formation by c-Src correlates with EGF-induced physical association of the EGFR with c-Src, c-Src-dependent phosphorylation of the receptor at two novel sites (Y845 and Yl101), and increased tyrosine phosphorylation of selected receptor substrates. Substitution of phenylalanine for Y845 ablates EGF- and serum-induced DNA synthesis, suggesting that phosphorylation of Y845 may be a critical regulator of EGF-mediated growth and may represent a novel target to be exploited for tumor therapy. However, whether this site is required for malignant transformation mediated by the EGFR is not known, nor is the mechanism of phospho-Y845 (pY845) action understood. Similarly, the mechanism of the interplay between HER2/3 and c-Src is unknown. To further investigate the dependency of EGF-induced breast cancer cell growth and tumorigenesis on pY845 and the nature of the HER2/3/c-Src interaction, the ability of an inducibly expressed mutant Y845F EGFR or microinjected peptides containing pY845 to inhibit breast cancer cell growth in culture or in nude mice will be directly tested, as will biological synergism between c-Src and EGFR and its dependency on Y845 phosphorylation in a transgenic mouse model. The downstream effectors of phosphorylated Y845 will also be identified from a panel of known EGFR substrates and from differential phage display libraries, using phosphorylated vs. unphosphorylated peptides containing Y845 as probes. Finally the influence of c-Src on HER2/3-promoted cell survival, growth, and migration will be explored in two cell culture/xenograft models that will allow one to investigate the interaction in a normal (not transformed) cell context. The long-term goal of these studies is to understand the biological consequences of c-Src/EGFR family member interactions and the biochemical mechanisms that underlie them, thereby identifying potential new targets for therapeutic intervention of breast and other cancers.

性状（申请人提供）：表皮生长因子成员 受体（EGFR）和c-Src酪氨酸激酶家族通常是 在人类肿瘤中共过表达。这种共过度表达表明， 这两个家族的成员可能在功能上相互作用以影响肿瘤的形成 和/或进展。最近在成纤维细胞模型中的研究结果 系统和人乳腺癌细胞系和肿瘤组织中的研究表明， c-Src和EGFR协同作用促进肿瘤形成。 证据还支持c-Src和其他两种蛋白质之间的功能相互作用。 EGFR家族成员，HER 2和HER 3。EGFR介导的增强 c-Src的肿瘤形成与EGF诱导的 EGFR与c-Src、c-Src依赖性磷酸化受体的结合 新的位点（Y845和Yl 101），以及增加的酪氨酸磷酸化， 选择受体底物。用苯丙氨酸取代Y845消除 EGF和血清诱导的DNA合成，表明Y845的磷酸化 可能是EGF介导的生长的关键调节因子， 靶点可用于肿瘤治疗。无论这个网站是 EGFR介导的恶性转化所需的蛋白质是未知的， 磷酸化Y845（pY 845）作用的机制。类似地， HER 2/3和c-Src之间相互作用的机制尚不清楚。进一步 研究EGF诱导的乳腺癌细胞生长的依赖性， pY 845上的肿瘤发生和HER 2/3/c-Src相互作用的性质， 诱导表达的突变型Y845 F EGFR或显微注射肽 含有pY 845以抑制乳腺癌细胞在培养物中或裸细胞中的生长 将直接测试小鼠，c-Src和 在转基因小鼠模型中EGFR及其对Y845磷酸化的依赖性。 磷酸化Y845的下游效应物也将从一个细胞中鉴定。 一组已知的EGFR底物和来自差异噬菌体展示文库， 使用含有Y845的磷酸化肽与未磷酸化肽作为探针。 最后，研究了c-Src对HER 2/3促进的细胞存活、生长和增殖的影响。 将在两种细胞培养/异种移植模型中探索迁移， 一个用于研究正常（未转化）细胞环境中的相互作用。 这些研究的长期目标是了解 c-Src/EGFR家族成员相互作用的后果和生物化学 机制，从而确定潜在的新目标， 乳腺癌和其他癌症的治疗干预。