Recovery of functional p53 as a therapeutic approach for breast cancer

恢复功能性 p53 作为乳腺癌的治疗方法

• 批准号: 7656966
• 负责人: SALMAN M HYDER
• 金额: $ 31.12万
• 依托单位: UNIVERSITY OF MISSOURI-COLUMBIA
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-01 至 2010-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7656966
• 关键词: Apoptosis; Apoptotic; Biological Assay; Breast Cancer Cell; CDKN1A gene; Cell Cycle Arrest; Cell Proliferation; Cells; DNA-Protein Interaction; Data; Development; Electrophoretic Mobility Shift Assay; Enzyme-Linked Immunosorbent Assay; Figs - dietary; Gene Targeting; Genes; Genetic Transcription; Growth; Hormone replacement therapy; Human; Immunohistochemistry; In Vitro; Incidence; Lead; Malignant Neoplasms; Mammary Neoplasms; Measures; Mediating; Methods; Modeling; Molecular Target; Monitor; Neoplasm Metastasis; Nude Mice; Nutrient; Pharmaceutical Preparations; Postmenopause; Production; Progesterone Receptors; Progestins; Protein Secretion; Protein p53; Proteins; Reaction; Recovery of Function; Regulatory Element; Research; Resistance; Reverse Transcriptase Polymerase Chain Reaction; Role; TP53 gene; Testing; Therapeutic; Time; Transfection; Tumor Suppressor Proteins; Vascular Endothelial Growth Factors; Western Blotting; Woman; Xenograft procedure; angiogenesis; antitumor drug; cancer risk; carcinogenesis; caspase-3; caspase-9; chromatin immunoprecipitation; in vivo; insight; malignant breast neoplasm; mouse model; mutant; neoplastic cell; novel strategies; oncoprotein p21; progesterone receptor positive; protein expression; research study; small molecule; tumor; tumor growth; tumor xenograft

Wild-type p53 tumor suppressor protein (wtp53) promotes cell cycle arrest and apoptosis and inhibits VEGF-dependent angiogenesis, which is required to support rapid tumor growth. In contrast, mutant p53 (mtp53) fails to inhibit VEGF-dependent angiogenesis and thereby permits rapid tumor growth. However, apoptosis can be restored in tumor cells by co-expression of wtp53 and mtp53 or by treatment with PRIMA-1 (p53 reactivation and induction of massive apoptosis), a small molecule activator of mtp53. We recently observed that in many tumor cells, the effect of mtp53 on VEGF is mediated by progestins and the progesterone receptor. Importantly, PRIMA-1 also blocks this reaction. These data suggest that mtp53, which is often expressed at a high level in tumor cells, might be a useful molecular target for anti-tumor drugs, if its wild-type function could be efficiently re-activated in vivo. Furthermore, such an approach might reduce breast cancer risk in women exposed to progestins (for example, during hormone replacement therapy). This proposal will explore the potential of this idea. The proposed research will test the following hypothesis: PRIMA-1 re-activates mtp53 and restores wtp53 function, thereby inhibiting cell proliferation, expression of VEGF, angiogenesis and metastasis, and stimulating apoptosis in p53-deficient breast tumor cells. The specific aims of the proposed research are: (1) Determine the mechanism by which PRIMA-1 induces cell-cycle arrest and/or apoptosis in p53-defective human breast tumor cells. (2) Determine the mechanism by which PRIMA-1 regulates expression of VEGF in p53-defective human breast tumor cells. (3) Characterize the effects of PRIMA-1 on incidence and progression of human breast tumor xenografts in nude mice. (4) Characterize the effects of PRIMA-1 on metastasis of human breast cancer cells in nude mice. The methods to be used include FACS, ELISA, Western blotting, immunohistochemistry, real-time RT-PCR, gelshift, chromatin immunoprecipitation and in vivo xenograft tumor mouse models. It is expected that the proposed research will yield valuable insights into the role of wtp53 and mtp53 in carcinogenesis. These studies should lead to the development of a novel approach for treating progestin-dependent and progestinindependent breast cancer in humans. Furthermore, we contend that the research will provide critical data relevant to minimizing breast cancer risk and metastasis in post-menopausal women and other women exposed to exogenous progestins.

野生型p53肿瘤抑制蛋白(Wtp53)促进细胞周期停滞和凋亡并抑制 血管内皮生长因子依赖的血管生成，这是支持肿瘤快速生长所必需的。相比之下，突变型p53 (Mtp53)不能抑制血管内皮生长因子依赖的血管生成，从而促进肿瘤的快速生长。然而， Wtp53和mtp53共表达或PRIMA-1治疗可恢复肿瘤细胞的凋亡 (P53重新激活和诱导大量细胞凋亡)，mtP53的小分子激活剂。我们最近 观察到在许多肿瘤细胞中，mtp53对血管内皮生长因子的影响是由孕激素和 孕激素受体。重要的是，PRIMA-1也能阻止这种反应。这些数据表明，mtp53，这是 通常在肿瘤细胞中高水平表达，如果它的分子靶点在抗肿瘤药物中有用 野生型功能可以在体内有效地重新激活。此外，这样的方法可能会减少乳房 暴露于孕激素的妇女的癌症风险(例如，在激素替代治疗期间)。这 提案将探索这一想法的潜力。这项拟议的研究将检验以下假设： Prima-1重新激活mtp53并恢复wtp53功能，从而抑制细胞增殖， 血管内皮生长因子在P53基因缺陷乳腺中的表达、血管生成和转移及促进细胞凋亡 肿瘤细胞。拟议研究的具体目标是：(1)确定PRIMA-1 诱导p53缺陷的人乳腺肿瘤细胞的细胞周期停滞和/或凋亡。(2)确定 PRIMA-1调节p53缺陷型人乳腺肿瘤细胞中血管内皮生长因子表达的机制(3) PRIMA-1对人乳腺肿瘤裸鼠移植瘤发生和发展的影响 老鼠。(4)研究PRIMA-1对人乳腺癌细胞裸鼠移植瘤转移的影响。这个 方法包括流式细胞术、酶联免疫吸附试验、Western blotting、免疫组织化学、实时RT-PCR、凝胶转移、 染色质免疫沉淀和体内异种移植瘤小鼠模型。预计将会有 拟议的研究将对wtp53和mtp53在癌症发生中的作用产生有价值的见解。这些 研究应该导致开发一种治疗孕激素依赖和孕激素非依赖性的新方法 人类患乳腺癌。此外，我们认为这项研究将提供关键数据 与减少绝经后妇女和其他妇女的乳腺癌风险和转移有关 暴露于外源性孕激素。