Malignant melanoma studies using iPS derived melanocytes and Zebrafish

 描述（由申请人提供）：癌症的特征是不受限制的自我更新细胞，最终形成剥夺健康组织资源的肿瘤。尽管以受控的方式，自我更新的能力由多能干细胞和成人中天然存在的祖细胞共享。这种共同的自我繁殖能力导致了这样的假设，即祖细胞可能更容易转化为癌症或更容易转化为不同的肿瘤表型。在几种肿瘤类型（横纹肌肉瘤，透明细胞肉瘤等）中工作证实了这一假设，而脑癌的结果则与之相矛盾。其他实验室最近的工作已经建立了成年人表皮内多能黑素细胞祖细胞的存在，为黑色素瘤从多能性和低分化细胞发生的可能性开辟了道路。揭示细胞起源的重要性将检验黑色素瘤产生的细胞决定其随后的临床行为的假设;提供基于其细胞起源而不仅仅是大量群体治疗恶性黑色素瘤的见解。 为了解决黑色素瘤的细胞来源的分化状态的影响，本研究将利用两个互补的系统：从iPS细胞衍生的人黑色素细胞和黑色素瘤的转基因斑马鱼模型。我们已经产生了一个强大的和可重复的协议，通过黑素细胞祖细胞从人类多能细胞色素黑素细胞的生产。我们将在确定的分化阶段引入致癌突变（包括BRAFv600e），并在体外和体内表征致瘤表型。为了补充人类细胞培养工作，我们将利用完善的体内斑马鱼黑色素瘤模型来驱动每个祖细胞阶段的细胞中的肿瘤发生。通过在谱系特异性基因的启动子下表达BRAFv600 e，我们可以查询起源细胞的分化状态对体内黑色素瘤表型的重要性。

 DESCRIPTION (provided by applicant): Cancer is characterized by unrestricted, self-renewing cells, eventually forming tumors that deprive healthy tissues of resources. Albeit in a controlled fashion, the ability to self-renew is shared by pluripotent stem cells and naturally present progenitors in the adult. This shared ability to self-propagate led to the hypothesis that progenitor cells may be more apt to transformation into cancer or apt to transform with distinct tumor phenotypes. Work in several tumor types (rhabdomyosarcoma, clear cell sarcoma, etc.) has confirmed the hypothesis, while results in brain cancer contradict. Recent work by other labs has established the presence of multipotent melanocyte progenitors within the epidermis of adult humans, opening up the possibility for melanoma genesis from a more pluripotent and less differentiated cell. Uncovering the importance of cell of origin will test the hypothesis that the ell in which melanoma arises dictates its subsequent clinical behavior; providing insights on treating malignant melanomas based on their cell of origin and not just the bulk population. To address the impact of the differentiation status of the cell of origin on melanoma this study will utilize two complementary systems: human melanocytes derived from iPS cells and a transgenic zebrafish model of melanoma. We have generated a robust and repeatable protocol for the production of pigmented melanocytes via melanocyte progenitors from human pluripotent cells. We will introduce oncogenic mutations (including BRAFv600e) at defined stages of differentiation and characterize the tumorigenic phenotypes both in vitro and in vivo. To complement the human cell culture work, we will utilize the well-established in vivo zebrafish melanoma model to drive tumorigenesis in cells at each progenitor stage. By expressing BRAFv600e under promoters for lineage specific genes we can query the importance of differentiation status of the cell of origin on melanoma phenotypes in vivo.