ROLE OF GROWTH FACTORS IN PROSTATE CANCER

生长因子在前列腺癌中的作用

基本信息

批准号：
3164576
负责人：
EVELYN R BARRACK
金额：
$ 21.45万
依托单位：
JOHNS HOPKINS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
1977
资助国家：
美国
起止时间：
1977-09-01 至 1994-08-31
项目状态：
已结题

项目摘要

Standard therapy for metastatic prostate cancer is androgen ablation, however, virtually all tumors become androgen-independent and the patient eventually relapses. Our long term goal is to understand the mechanisms of growth control in androgen-independent prostate cancer; such knowledge may ultimately allow the design of new therapies. We found that overexpression of transforming growth factor beta1 (TGFbeta1) in rat prostate cancer cells dramatically affected their growth in vivo and in vitro, and we found TGFbeta1 levels were higher in prostate cancer than normal prostate. We postulate that TGFbeta1 produced by prostate cancer cells is an important autocrine and paracrine regulator of prostate cancer growth. The goal of this proposal is to further test this hypothesis and to investigate the molecular mechanisms involved in these effects. Aim 1 is to investigate the role of TGFbeta1 in rat prostate cancer cell proliferation. To do this, the growth of nontransfected cells, cells stably transfected with sense TGFbeta1 cDNA, and cells stably transfected with antisense TGFbeta1 DNA will be studied in vivo and in vitro. Growth in vitro will be studied in the absence vs. presence of exogenously added TGFbeta1, or TGFbeta neutralizing antibody. These studies will be carried out using the Dunning R3327-MATLyLu, -AT2 and -G prostate cancer cell lines which form tumors in rats that differ in metastatic potential, growth rate, degree of differentiation, and sensitivity to androgen. Aim 2 is to study the molecular mechanisms of action of TGFbeta1 in prostate cancer cells. Using nontransfected and transfected MATLyLu, AT2, and G cells, we will investigate the effects of TGFbeta1 on TGFbeta receptor levels and production of other growth factors. We will also investigate the role of adenylyl cyclase and G proteins in TGFbeta1 signal transduction. Aim 3 is to study the production and processing of TGFbeta protein. Immunoblot analysis will be used to characterize the TGFbeta polypeptides that are produced and secreted by the different prostate cancer cell lines. Antibodies will be used to determine whether multiple polypeptides are produced and whether processing of the precursor is normal. Aim 4 is to study TGFbeta expression in human prostate cancer. We will analyze TGFbeta expression (mRNA levels and immunohistochemical staining) in normal human prostate and prostate cancer (different stages and grades). If TGFbeta expression is elevated in cancer, its effect on human prostate cancer growth will be evaluated by stable transfection of human prostate cancer cell lines (DU145, PC3) with TGFbeta1 cDNA, and growth of TGFbeta1- overproducing subclones in vitro and in nude mice in vivo.

转移性前列腺癌的标准疗法是雄激素消除，然而，几乎所有肿瘤都变得不依赖雄激素，并且患者最终复发。我们的长期目标是了解雄激素非依赖性前列腺癌的生长控制；这些知识可能最终允许设计新疗法。我们发现过度表达转化生长因子β1 (TGFbeta1) 在大鼠前列腺癌细胞中的作用极大地影响了它们在体内和体外的生长，我们发现前列腺癌中的 TGFbeta1 水平高于正常前列腺。我们假设前列腺癌细胞产生的 TGFbeta1 是一种重要的前列腺癌生长的自分泌和旁分泌调节剂。目标是本提案旨在进一步检验这一假设并调查这些效应涉及的分子机制。目标 1 是调查 TGFbeta1 在大鼠前列腺癌细胞增殖中的作用。要做的事未转染细胞、稳定转染细胞的生长有义 TGFbeta1 cDNA，以及反义 TGFbeta1 稳定转染的细胞 DNA 将在体内和体外进行研究。将研究体外生长不存在与存在外源添加 TGFbeta1 或 TGFbeta 的情况中和抗体。这些研究将使用邓宁 R3327-MATLYLu、-AT2 和 -G 前列腺癌细胞系在大鼠的转移潜能、生长速度、程度不同分化和对雄激素的敏感性。目标 2 是研究 TGFbeta1 在前列腺癌细胞中作用的分子机制。使用未转染和转染的 MATLyLu、AT2 和 G 细胞，我们将研究 TGFbeta1 对 TGFbeta 受体水平的影响其他生长因子的产生。我们还将调查的作用 TGFbeta1 信号转导中的腺苷酸环化酶和 G 蛋白。目标 3 是研究TGFbeta蛋白的生产和加工。免疫印迹分析将用于表征 TGFbeta 多肽由不同的前列腺癌细胞系产生和分泌。抗体将用于确定多个多肽是否是生产情况以及前体加工是否正常。目标 4 是研究人类前列腺癌中 TGFbeta 的表达。我们将分析TGFbeta 正常人中的表达（mRNA 水平和免疫组织化学染色）前列腺和前列腺癌（不同阶段和级别）。如果转化生长因子β 在癌症中表达升高，其对人类前列腺癌的影响将通过人前列腺癌的稳定转染来评估生长情况具有 TGFbeta1 cDNA 的细胞系（DU145、PC3）以及 TGFbeta1- 的生长在体外和裸鼠体内过量产生亚克隆。