Cripto Antagonism of Activin and TGF-Beta Signalling

激活素和 TGF-β 信号传导的 Cripto 拮抗作用

• 批准号: 7426782
• 负责人: WYLIE W. VALE
• 金额: $ 28.95万
• 依托单位: SALK INSTITUTE FOR BIOLOGICAL STUDIES
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-06-01 至 2009-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7426782
• 关键词: Activins; Affinity Labels; Antibodies; Binding; Biological Models; Breast; Breast Cancer Cell; Breast Cancer Model; CFC1 gene; Cell Line; Cell Proliferation; Cells; Complex; Development; Differentiation and Growth; Disease; Disruption; Embryonic Development; Epithelial; Epithelial Cells; Glycoproteins; Growth; Homeostasis; Human; In Vitro; Inhibin-beta Subunits; Lead; Ligands; MCF7 cell; Mammary Neoplasms; Mammary gland; Mediating; Mesoderm; Molecular; Mus; Nodal; Normal tissue morphology; Oncogene Proteins; Oncogenic; Phosphorylation; Play; Protein Overexpression; Proteins; Radiolabeled; Reagent; Role; Signal Pathway; Signal Transduction; Structure; TGF-beta type I receptor; Testing; Therapeutic; Tissues; Transforming Growth Factor beta; Transforming Growth Factor beta Receptors; Type II Activin Receptors; activin B; affinity labeling; cardiogenesis; cell type; crosslink; design; extracellular; improved; in vitro Model; malignant breast neoplasm; malignant phenotype; member; neoplastic; neutralizing antibody; novel; prevent; radiotracer; reagent testing; receptor; research study; response; therapeutic target; tumor; tumorigenesis

DESCRIPTION (provided by applicant): TGF-B and activin are functionally related members of the TGF-Beta superfamily of growth and differentiation factors. TGF-Beta and activin activate Smad2 and Smad3 and they both regulate tissue homeostasis by potently inhibiting proliferation of multiple cell types, including epithelial cells. Disruption of the antiproliferative response to activin and/or TGF-Beta is associated with dysregulated cellular proliferation, oncogenesis and progression toward the malignant phenotype. Cripto is a developmental oncoprotein that is overexpressed in multiple human tumors including approximately 80% of human breast tumors. Cripto overexpression transforms mammary epithelial ceils and activates the growth promoting Erk/MAPK and PI3K signaling pathways. Cripto and related EGF-CFC proteins also play essential signaling roles during embryonic development and Cripto is required for mesoderm induction and cardiogenesis. It has been shown that Cripto acts as a coreceptor to facilitate receptor assembly and signaling via activin type II/I receptors by the TGF-Beta superfamily members nodal, Vgl and GDF1. This led us to test whether Cripto may regulate the ability of activin and possibly other TGF-Beta ligands to assemble functional receptor complexes and we showed that Cripto binds activin in the presence of type II activin receptors, competes with ALK4 for binding to activin and antagonizes activin signaling. We now have evidence showing that Cripto also binds TGF-Beta in the presence of TBRII, competes with ALK5 for TGF-Beta binding and antagonizes TGF-Beta signaling; we propose, therefore, that Cripto may be generally capable of blocking antiproliferative Smad2/3 signals. Under Aim I of this proposal we will identify the molecular determinants on Cripto that mediate Cripto binding to activin/TFG-Beta and antagonism of activin/TGF-Beta signaling. We also propose to develop reagents including anti-Cripto neutralizing antibodies designed to prevent the ability of Cripto to antagonize activin and TGF-Beta signaling. Aim II proposes to characterize the ability of Cripto to block type I receptor recruitment to ligand-type II receptor complexes and block type I receptor phosphorylation in breast cancer cells in vitro in response to activin/TGF-Beta and the ability of Cripto to block phosphorylation of Smad2/3 following activin/TGF-beta treatment of breast cancer cells in vitro. Under Aim III we will characterize the effects of Cripto on activin/TGF-Beta-induced growth inhibition in three mammary epithelial-derived cell lines: MCF-7; MCF-10A; and CID-9 cells. Together, these studies will lead to an improved understanding of the mechanisms of Cripto action and will help illuminate therapeutic targets for the management of neoplastic disease.

描述（由申请人提供）：TGF-B和激活素是生长和分化因子TGF-Beta超家族的功能相关成员。 TGF-Beta 和激活素激活 Smad2 和 Smad3，它们都通过有效抑制多种细胞类型（包括上皮细胞）的增殖来调节组织稳态。对激活素和/或TGF-β的抗增殖反应的破坏与细胞增殖失调、肿瘤发生和恶性表型的进展有关。 Cripto 是一种发育癌蛋白，在多种人类肿瘤（包括大约 80% 的人类乳腺肿瘤）中过度表达。 Cripto 过度表达可转化乳腺上皮细胞并激活促进生长的 Erk/MAPK 和 PI3K 信号通路。 Cripto 和相关的 EGF-CFC 蛋白也在胚胎发育过程中发挥重要的信号作用，并且 Cripto 是中胚层诱导和心脏发生所必需的。研究表明，Cripto 作为辅助受体，通过 TGF-Beta 超家族成员 nodal、Vgl 和 GDF1 通过激活素 II/I 型受体促进受体组装和信号传导。这促使我们测试 Cripto 是否可以调节激活素和可能的其他 TGF-β 配体组装功能性受体复合物的能力，并且我们表明 Cripto 在 II 型激活素受体存在的情况下结合激活素，与 ALK4 竞争与激活素的结合并拮抗激活素信号传导。我们现在有证据表明，Cripto 在 TBRII 存在的情况下也能结合 TGF-Beta，与 ALK5 竞争 TGF-Beta 结合并拮抗 TGF-Beta 信号传导；因此，我们认为 Cripto 通常能够阻断抗增殖 Smad2/3 信号。在本提案的目标 I 下，我们将鉴定 Cripto 上介导 Cripto 与激活素/TFG-Beta 结合以及激活素/TGF-Beta 信号传导拮抗作用的分子决定因素。我们还建议开发包括抗 Cripto 中和抗体在内的试剂，旨在防止 Cripto 拮抗激活素和 TGF-Beta 信号传导的能力。 Aim II 拟表征 Cripto 在体外响应激活素/TGF-Beta 阻断 I 型受体募集至配体 II 型受体复合物并阻断乳腺癌细胞中 I 型受体磷酸化的能力，以及 Cripto 在体外激活素/TGF-β 处理乳腺癌细胞后阻断 Smad2/3 磷酸化的能力。在目标 III 下，我们将描述 Cripto 对激活素/TGF-Beta 诱导的三种乳腺上皮衍生细胞系生长抑制的影响：MCF-7；MCF-7； MCF-10A；和CID-9细胞。总之，这些研究将加深对 Cripto 作用机制的理解，并有助于阐明肿瘤疾病管理的治疗目标。

项目成果

Blockade of Cripto binding to cell surface GRP78 inhibits oncogenic Cripto signaling via MAPK/PI3K and Smad2/3 pathways.

• DOI: 10.1038/onc.2009.97
• 发表时间: 2009-06-18
• 期刊: ONCOGENE
• 影响因子: 8
• 作者: Kelber, J. A.;Panopoulos, A. D.;Shani, G.;Booker, E. C.;Belmonte, J. C.;Vale, W. W.;Gray, P. C.
• 通讯作者: Gray, P. C.