Dissecting Phenotype Switching in Early Stage Melanomas

项目摘要 黑色素瘤仍然是一种毁灭性的癌症。早期黑色素瘤占黑色素瘤的大多数。 在美国进行诊断和管理。越来越清楚的是，转移性传播和播种 在肿瘤进展过程中发生非常早，而肿瘤仍然局限于皮肤，没有其他迹象。 器官参与。为了有效地与这种疾病作斗争，我们必须了解 生物学早期肿瘤，特别是宿主对肿瘤细胞的防御机制。基础研究 在过去的几十年里，早期黑色素瘤没有取得重大进展，主要是由于缺乏鼠 模拟早期疾病的系统。黑色素瘤的基因工程小鼠模型代表了许多 缺点，最好的情况下，它们模拟小鼠免疫内的晚期侵袭性肿瘤（鼠基因组）。 系统在这个提议中，我们将在新的体内人源化鼠模型中模拟早期恶性状态， 我们已经开发了，其中高度免疫缺陷的小鼠用人CD34+造血重建， 干细胞并用HLA-A等位基因匹配的人黑素瘤细胞攻击。紫外线（UVB/A） 辐射，我们将诱导额外的突变，在人类皮肤，并研究肿瘤的进展，因为他们 在时间和空间中成长。我们的初步研究表明，转录开关发生在 肿瘤细胞，它伴随着独特的宿主免疫反应，这种串扰决定了肿瘤细胞的命运。 肿瘤进展或消除。干扰素刺激物-STING-信号传导一旦被激活 黑色素瘤细胞获得侵袭性表型，表明其在肿瘤进展中的作用。这里我们 建议在非侵袭性黑色素瘤转变为恶性黑色素瘤的概念中建立范式转变， 侵袭性表型将直接影响临床实践。我们将研究：1）肿瘤内的变化 （突变，途径），共同发生在免疫微环境（细胞谱系，信号）在早期 使用人源化小鼠模型的疾病进展（Aim 1），2）在存在下的促肿瘤或抗肿瘤应答 或在利用人源化小鼠和3D皮肤模型的早期疾病中不存在STING激活（Aim 1）， 3)通过调节免疫细胞亚群逆转表型和测试因果关系（目的2），和4） 开发和验证应用于早期黑色素瘤的预测存活率的预后测定法（Aim 3）。 该项目的成功完成有望为黑色素瘤（和癌症）领域带来新的模型系统 能够研究人类肿瘤和人类免疫系统的相互作用。如果在早期阶段提供了一个重大飞跃 黑色素瘤研究，并通过揭示新的肿瘤细胞内在或外在加深我们的理解 疾病进展的机制。

Project Summary Melanoma continues to be a devastating cancer. Early stage melanomas represent the majority of melanomas that are diagnosed and managed in the US. It is becoming clearer that metastatic dissemination and seeding occurs very early during tumor progression while the tumor is still localized to the skin without signs of other organ involvement. To effectively battle with this disease we must understand the molecular underpinnings of biologically early tumors, in particular host defense mechanisms against the tumor cells. Basic research in early melanomas has not made significant progress over the past decades mostly due to lack of murine systems that model early disease. Genetically engineered murine models of melanoma represent many shortcomings, and at best they mimic late aggressive tumors (murine genome) within the mice immune system. In this proposal, we will mimic early malignant states in novel in vivo humanized murine models that we have developed, in which highly immune deficient mice are reconstituted with human CD34+ hematopoietic stem cells and challenged with HLA-A allele-matched human melanoma cells. By ultraviolet (UVB/A) irradiation, we will induce additional mutations as in human skin, and study the progression of tumors as they grow in time and space. Our preliminary studies indicate that a transcriptional switch occurs within the tumor cells, it accompanies unique host immune responses, and this crosstalk dictates the fate of the tumor towards progression or elimination. Stimulator of interferon – STING – signaling gets activated once melanoma cells acquire an aggressive phenotype suggesting a role during tumor progression. Here, we propose to establish paradigm-shifts in the concept of non-aggressive melanomas transitioning into an aggressive phenotype that will directly impact clinical practice. We will investigate: 1) changes within the tumor (mutations, pathways) that co-occur within the immune microenvironment (cell lineages, signals) during early disease progression using humanized mouse models (Aim1), 2) pro- or anti-tumor responses in the presence or absence of STING activation in early disease leveraging the humanized mouse and 3D skin models (Aim 1), 3) reversal of phenotypes and testing causality by modulating immune cell subpopulations (Aim 2), and 4) development and validation of a prognostic assay applied to early melanomas that predicts survival (Aim 3). Successful completion of this project promises to bring new model systems to the melanoma (and cancer) field that enable studying human tumor and human immune system interactions. If offers a major leap in early stage melanoma research, and deepens our understanding by revealing new tumor cell intrinsic or extrinsic mechanisms of disease progression.