TRANSCRIPTION FACTOR AP2 IN METASTASIS OF MELANOMA

描述：(逐字改编自调查人员摘要) 与黑色素瘤细胞从 径向生长阶段(RGP)到垂直生长阶段(VGP)(转移性 表型)的定义不是很好。这个实验室最近的工作 证明了细胞表面黏附分子的表达 MCAM/MUC18，直接属于免疫球蛋白超家族 与人类黑色素瘤细胞的转移潜能有关。而当 在所检测的MCAM/MUC18阴性细胞系中，没有发现有 转移性，将MCAM/MUC18基因导入此类细胞 在裸鼠体内转移。此外，我们最近还展示了 黑色素瘤的进展与该基因的表达缺失有关 C-KIT原癌基因酪氨酸激酶受体。此外，重新表达 高转移细胞系中c-kit受体的表达抑制其 裸鼠体内的致瘤性和转移潜能。事实上，曝光 C-kit阳性黑色素瘤细胞体内外对干细胞因子的作用 C-kit的配体(SCF)触发了这些细胞的凋亡，但不是 正常的黑素细胞。 哺乳动物转录因子AP-2是一种序列特异性DNA结合因子 在神经脊谱系中表达的蛋白质，受维甲酸调节。 我们的初步数据表明，MCAM/MUC18和c-kit基因都是 其表达受AP-2的高度调控。此外，其他基因也是 参与黑色素瘤的进展，如基质金属蛋白酶-2，贝尔-2，E-钙粘附素， P21/WAF-1也受转录因子AP-2的调控。我们的 实验室最近观察到，虽然有几个 非转移性黑色素瘤细胞株表达高转移细胞AP-2 各株系不表达该转录因子。因此，我们假设 AP-2表达的丧失可能是骨肉瘤发生发展过程中的一个关键事件 恶性黑素瘤。 因此，我们提出三个具体目标：1)提供一个 AP-2参与收购的直接证据 用W.T.转染转移细胞的转移表型。AP-2和 AP-2B基因显性阴性的原代黑色素瘤细胞 随后分析它们在裸鼠体内的成瘤性和转移潜能。 老鼠。2)研究AP-2和AP-2B对血管内皮生长因子表达的影响。 以上提到的基因。3)评估AP-2的表达状况，并 特征性黑色素瘤患者肿瘤标本的功能 数据库。这些实验将产生有价值的信息 黑色素瘤的进展，有助于开发新的分子分期标记物 也是抗肿瘤/转移治疗的共同靶点。

DESCRIPTION: (adapted verbatim from investigator's abstract) The molecular changes associated with the transition of melanoma cells from radial growth phase (RGP) to vertical growth phase (VGP) (metastatic phenotype) are not very well defined. Recent work from this laboratory demonstrated that the expression of the cell surface adhesion molecule MCAM/MUC18, which belongs to the immunoglobulin superfamily, directly correlates with the metastatic potential of human melanoma cells. While none of the MCAM/MUC18-negative cell lines examined have been found to be metastatic, transfection of such cells with MCAM/MUC18 gene rendered them metastatic in nude mice. In addition, we have recently demonstrated that the progression of melanoma is associated with loss of expression of the c-KIT proto-oncogene tyrosine kinase receptor. Furthermore, re-expression of the c-KIT receptor in highly metastatic cell lines inhibited their tumorigenicity and metastatic potential in nude mice. Indeed, exposure of c-KIT-positive melanoma cells in vitro and in vivo to stem cell factor (SCF), the ligand for c-KIT, triggered apoptosis of these cells but not of normal melanocytes. The mammalian transcription factor AP-2 is a sequence-specific DNA-binding protein expressed in neural crest lineages and regulated by retinoic acid. Our preliminary data indicate that both MCAM/MUC18 and c-KIT gene expression is highly regulated by AP-2. In addition, other genes that are involved in the progression of melanoma such as MMP-2, bel-2, E-cadherin, and p21/WAF-1 are also regulated by the transcription factor AP-2. Our laboratory has recently made the observation that while several nonmetastatic melanoma cell lines express AP-2, the highly metastatic cell lines do not express this transcription factor. Therefore, we hypothesize that loss of AP-2 expression may be a crucial event in the development of malignant melanoma. We are therefore proposing the three Specific Aims: 1) to provide a direct evidence for the involvement of AP-2 in the acquisition of the metastatic phenotype by transfecting metastatic cells with w.t. AP-2 and primary melanoma cells with a dominant negative AP-2B genes and subsequently analyze their tumorigenicity and metastatic potential in nude mice. 2) To study the effect of AP-2 and AP-2B on the expression of the above mentioned genes. 3) To evaluate the status of AP-2 expression and function in tumor specimens from patients in well-characterized melanoma database. These experiments will generate valuable information on the progression of melanoma, and help to develop new molecular staging markers and a common target for anti-tumor/metastasis therapy.