CYLD Regulation of Epidermal Growth and Neoplasia

描述（由申请人提供）： 最近的研究已经建立了cyld与家族性和散发性肿瘤的遗传联系，这些肿瘤主要来自皮肤附属器的表皮细胞，与表面表皮细胞不同。CYLD作为一种去泛素化酶，抑制TRAF 2/TRAF 6蛋白的自我泛素化，TRAF 2/TRAF 6蛋白是介导细胞表面受体信号转导的关键衔接分子，从而抑制下游信号通路，包括NF-？B和JNK信号级联。一个先前预测的作用，典型的NF-？皮肤肿瘤病因学中的B途径最近受到了以下发现的挑战：揭示了在TPA诱导的cyld-/-小鼠表皮细胞过度增殖中NF-κ B RelA功能未改变。此外，我们最近已经证明，NF-？B在表皮生长控制中至关重要，其阻断以JNK/AP 1功能依赖性方式促成鳞状细胞癌（SCC）。这些发现使我们推测CYLD抑制通过JNK级联反应促进肿瘤形成。本研究的第一个目标是确定CYLD调节表皮细胞生长的机制，并探讨JNK信号级联是否在CYLD对表皮稳态的影响中发挥核心作用。为此，我们将从手术处理的包皮或成人皮肤中分离出多种类型的原代人表皮细胞，并研究它们对基因修饰的CYLD功能以及JNK信号传导的生长反应。第二个目标是通过产生小鼠和人的转基因皮肤组织来研究CYLD驱动的体内肿瘤形成。我们将研究是否抑制或增加NF-？B、JNK或Ras-MAPK信号级联将预防或增强CYLD诱导的瘤形成。通过这一建议的最后，我们希望已经确定了CYLD调节表皮稳态和皮肤上皮肿瘤的机制。这项工作是基于这样的前提，即表征CYLD介导的细胞生长和皮肤组织肿瘤形成的分子机制将为基础上皮生物学提供新的见解，并表征人类皮肤疾病的治疗靶点。

DESCRIPTION (provided by applicant): Recent studies have established a genetic linkage of cyld to both familial and sporadic neoplasms that mostly arise from the epidermal cells of skin appendages, as distinct from surface epidermal cells. CYLD acts as a deubiquitinase that inhibits self-ubiquitination of TRAF2/TRAF6 proteins, the key adaptor molecules mediating signal transduction from cell surface receptors, and thereby inhibit downstream signaling pathways, including NF-?B and JNK signaling cascades. A previously predicted role for the canonical NF-?B pathway in the etiology of skin neoplasms was recently challenged by findings revealing unaltered NF-KB RelA function in the TPA-induced hyperproliferation of cyld-/- mice epidermal cells. In addition, we have recently demonstrated that NF-?B is crucial in epidermal growth control and its blockade contributes to squamous cell carcinoma (SCC) in a JNK/AP1 function dependent manner. These finding lead us to hypothesize that CYLD inhibition acts through JNK cascade to promote neoplasia. The first goal of this study is to define the mechanisms of CYLD regulation of epidermal cell growth and to explore whether the JNK signaling cascade play a central role in CYLD effects on epidermal homeostasis. To do this, we will isolate multiple types of primary human epidermal cells from surgically disposed foreskin or adult skin and study their growth response to genetically modified CYLD function, as well as JNK signaling. The second goal is to study CYLD-driven neoplasia in vivo by generating both mice and human transgenic skin tissue. We will investigate whether inhibiting or augmenting NF-?B, JNK or Ras-MAPK signaling cascades will prevent or potentiate CYLD induced neoplasia. By the end of this proposal, we hope to have determined the mechanism of CYLD regulation of epidermal homeostasis and cutaneous epithelial neoplasms. This effort is based on the premise that characterizing the molecular mechanisms in CYLDmediated cell growth and neoplasia in skin tissue will both provide new insights into basic epithelial biology as well as characterize therapeutic targets for human skin diseases.