TRANSFORMING GROWTH FACTOR-B EXPRESSION IN MELANOMA DEVELOPMENT AND PROGRESSION

这个应用程序的目标是定义肿瘤相关基因的作用 转化生长因子-β在恶性肿瘤发生发展中的作用 黑色素瘤。该小组之前的工作表明，转化生长因子-β是 原发和恶性的结构性和持续性表达 尽管转化生长因子-β抑制黑色素瘤的生长，但黑色素瘤的体外和原位研究 在试管中。根据这些观察结果，我们推测转化生长因子-β 在体内发挥对黑色素瘤发展至关重要的作用， 因此，超过了在体外观察到的生长抑制作用。相关 转化生长因子-β的作用包括改变黏附分子和 黑色素瘤细胞蛋白水解酶、宿主细胞局部募集 肿瘤生长和转移扩散，抑制免疫反应 肿瘤细胞。来自其他肿瘤系统的间接证据表明 转化生长因子-β对所有这些现象都有重大贡献。这个 建议的实验代表了一种直接的方法来确定 黑色素瘤来源的转化生长因子-β的这些潜在作用是必不可少的 黑色素瘤的发展。 黑色素瘤细胞系来源于不同的进展阶段和 确定的致瘤性、转移能力、免疫原性和转化生长因子-β 作用是通过上调或抑制转化生长因子-β的产生实现的 利用正义、反义和负显性表达载体 选择细胞系，然后深入分析肿瘤的生长和 转移行为。通过对裸鼠体内致瘤性的研究，探讨了其对裸鼠致瘤性的影响。 转化生长因子-β在非致瘤性人原代黑色素瘤细胞中的过表达 WM1650。通过抑制转化生长因子-1来分析对转移行为的影响 高转移性人1205-LU细胞中β的产生。对……的影响 通过下调转化生长因子-β的产生来检测免疫原性 非免疫原性小鼠K1735黑色素瘤细胞变异体及其后续 同基因、免疫活性小鼠免疫原性的测定。在……里面 体外研究将集中在转化生长因子-β对粘连的依赖作用， 黏附分子和蛋白水解酶的迁移和调控 黑色素瘤细胞；免疫学研究将集中在转化生长因子-β的作用上 在不同的淋巴细胞亚群上。 这些研究的长期目标是确定黑色素瘤- 衍生的转化生长因子-β提供了一个合适的治疗靶点。

The goal of this application is to define the role of tumor-associated transforming growth factor (TGF)-beta in the development of malignant melanoma. Previous work by this group demonstrated that TGF-beta is constitutively and persistently expressed by primary and malignant melanomas in vitro and in situ although TGF-beta inhibits melanoma growth in vitro. Based on these observations it is hypothesized that TGF-beta exerts effects in vivo that are essential to melanoma development and, thus, outweigh the growth-inhibitory effects observed in vitro. Relevant effects of TGF-beta include altered expression of adhesion molecules and proteolytic enzymes by melanoma cells, recruitment of host cells for local tumor growth and metastatic spread, and suppression of immune responses to tumor cells. Indirect evidence from other tumor systems suggests significant contributions of TGF-beta to all of these phenomena. The proposed experiments represent a direct approach to determine which of these potential effects of melanoma-derived TGF-beta are essential to melanoma development. Melanoma cell lines derived from distinct stages of progression and with defined tumorigenicity, metastatic capacity, immunogenicity, and TGF-beta effects is achieved by upregulation or suppression of TGF-beta production using sense, antisense, and negative dominant expression vectors in selected cell lines followed by in depth analysis of tumor growth and metastatic behavior. Effects on tumorigenicity in nude mice are studied by overexpressing TGF-beta in the non-tumorigenic human primary melanoma cell WM 1650. Effects on metastatic behavior are analyzed by suppressing TGF- beta production in the highly metastatic human 1205-LU cells. Effects on immunogenicity are examined by downmodulation of TGF-beta production in non-immunogenic mouse K1735 melanoma cell variants and the subsequent determination of immunogenicity in syngeneic, immunocompetent mice. In vitro studies will focus on TGF-beta dependent effects on adhesion, migration, and modulation of adhesion molecules and proteolytic enzymes in melanoma cells; immunological studies will focus on the effects of TGF-beta on different lymphocyte subsets. The long-term goal of these studies is to determine whether melanoma- derived TGF-beta provides a suitable therapeutic target.