TRH Production and Regulation by Human Melanoma

应聘者描述(申请人提供)：应聘者是一名内科肿瘤学家，1998年在安德森癌症中心任教期间获得博士学位。1999年，她辞去临床教职，在生物免疫治疗系伊丽莎白·格林博士的实验室接受了T32培训补助金(T32 CA72371，Gabriel Lopez-Berestein博士)，成为博士后研究员。候选人的长期职业目标是成为一名独立研究员和一家实验室的负责人，该实验室专注于黑色素瘤生物和免疫治疗领域的转化研究。申请者的直接目标是制定研究计划，获得资金，并实施该计划，以实现拟议的具体目标；并通过R01机制制定一个纵向研究计划，提供资金。其目的是在M.D.安德森癌症中心开展拟议的研究，利用黑色素瘤肿瘤银行提供的组织资源。这项研究建议是基于观察到葡萄膜黑色素瘤和皮肤黑色素瘤患者中甲状腺功能低下的高患病率。假设黑色素瘤产生和分泌促甲状腺激素释放激素(TRH)作为一种自分泌生长因子，结合并激活黑素皮质素-1受体(MC1-R)；黑色素瘤产生的TRH受正常下丘脑TRH控制机制的调节。这些机制包括低水平的循环甲状腺激素刺激TRH(甲状腺功能减退症)；瘦素水平升高，通过瘦素受体的长亚型传递信号；以及(-黑素细胞刺激素通过黑素皮质素-4受体(MC4-R)传递信号。初步数据表明，TRH信息和蛋白存在于原发黑色素瘤和黑色素瘤细胞系中。在这些品系中也发现了MC1-R。第一个具体目的是验证TRH作为黑色素瘤自分泌生长因子的作用。黑色素瘤细胞表达TRH已在先前的实验中得到证实。分泌物将用放射免疫测定法进行检测和定量。免疫共沉淀和cAMP的测定将建立TRH对MC1-R的结合和激活。TRH对增殖和迁移的影响也将被研究。在特定的目标#2中，细胞系将用于体外研究，以确定下丘脑TRH调节的一个或多个机制是否与控制黑色素瘤细胞TRH的产生有关。

DESCRIPTION (provided by applicant): The candidate is a medical oncologist who obtained a Ph.D. degree in 1998 while on clinical faculty at the M.D. Anderson Cancer Center. In 1999, she left her clinical faculty position to train as a postdoctoral fellow in the laboratory of Dr. Elizabeth Grimm, Department of Bioimmunotherapy, under a T32 training grant (T32 CA72371, Dr. Gabriel Lopez-Berestein). The long-term career goal of the candidate is to become an independent researcher and head of a laboratory that is focused on translational research in the area of biologic and immunologic therapy for melanoma. The immediate goals of the applicant are to develop a research plan, obtain funding, and carry out that plan to achieve the proposed specific aims; and to develop a longitudinal research plan with funding through the R01 mechanism. The intent is to carry out the proposed research at the M.D. Anderson Cancer Center, with tissue resources available through the Melanoma Tumor Bank. The research proposal is based on the observation of a high prevalence of hypothyroidism among patients with uveal and cutaneous melanoma. It is hypothesized that melanomas produce and secrete thyrotropin-releasing hormone (TRH) as an autocrine growth factor that binds and activates the melanocortin-1 receptor (MC1-R); and that TRH production by melanomas is regulated by TRH control mechanisms functioning normally in the hypothalamus. These mechanisms include stimulation of TRH by low levels of circulating thyroid hormone (hypothyroidism); elevated levels of leptin, signaling through the long isoform of the leptin receptor; and (-melanocyte stimulating hormone signaling through the melanocortin-4 receptor (MC4-R). Preliminary data demonstrate the presence of TRH message and protein in primary melanomas and melanoma cell lines. MC1-R has also been identified in these lines. The first specific aim proposes to verify the role of TRH as an autocrine growth factor for melanoma. Expression of TRH by melanoma cells has been demonstrated in previous experiments. Secretion will be detected and quantified by radioimmunoassay. Co-immunoprecipitation and measurement of cAMP will establish binding and activation of MC1-R by TRH. Effects of TRH on proliferation and migration will also be examined. In Specific Aim #2, cell lines will be used for in vitro studies to determine if one or more of the mechanisms of hypothalamic TRH regulation are relevant to the control of TRH production by melanoma cells.