TRH Production and Regulation by Human Melanoma

描述（由申请人提供）：该候选人是医学肿瘤学家，于1998年在M.D.安德森癌症中心临床教师获得博士学位。1999年，她在T32培训基金（T32 CA72371， Gabriel Lopez-Berestein博士）资助下，离开临床教师岗位，到生物免疫治疗学系Elizabeth Grimm博士实验室接受博士后培训。候选人的长期职业目标是成为一名独立研究员和实验室负责人，专注于黑色素瘤生物和免疫治疗领域的转化研究。申请人的近期目标是制定研究计划，获得资助，并执行该计划以达到拟议的具体目标；并通过R01机制制定纵向研究计划。目的是在M.D.安德森癌症中心进行拟议的研究，并通过黑色素瘤肿瘤库获得组织资源。该研究计划是基于观察到葡萄膜和皮肤黑色素瘤患者中甲状腺功能减退的高发率。假设黑色素瘤产生并分泌促甲状腺激素释放激素（TRH）作为一种结合并激活黑素皮质素-1受体（MC1-R）的自分泌生长因子；黑素瘤的TRH产生受TRH控制机制的调节，TRH控制机制在下丘脑中正常运作。这些机制包括低水平的循环甲状腺激素（甲状腺功能减退）刺激TRH；瘦素水平升高，通过瘦素受体长异构体发出信号；以及通过黑素皮质素-4受体（MC4-R）的（-黑素细胞刺激激素）信号。初步数据表明，TRH信息和蛋白存在于原发性黑色素瘤和黑色素瘤细胞系中。MC1-R也在这些细胞系中被发现。第一个具体目的是验证TRH作为黑色素瘤的自分泌生长因子的作用。TRH在黑色素瘤细胞中的表达已在先前的实验中得到证实。分泌物将通过放射免疫法检测和定量。cAMP的共免疫沉淀和测定将建立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Specific Aim #2中，细胞系将用于体外研究，以确定下丘脑TRH调节的一种或多种机制是否与黑色素瘤细胞对TRH产生的控制有关。

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.