SELECTIVE MANIPULATION OF GENE EXPRESSION IN SKIN

一个合作项目将使用单链合成DNA 形成靶向DNA调控的三链结构的寡核苷酸 区域(TFO)来测试它们可能被用作 皮肤细胞功能障碍的基因特异性治疗。皮肤是一个理想的模型 用于基因操作，因为它可以很容易地进行评估和种植 体外培养。牛皮癣和皮肤癌将成为选择性治疗的目标 操纵。在第一个项目中，合成的寡核苷酸类似物 将被设计成靶向表皮生长的启动子区域 因子受体基因(EGF-R)及其选择性结合能力的检测 高表达EGF-R对A431表皮癌细胞系的抑制作用 EGF-R由于银屑病过度表达EGF-R和结合的转化生长因子-α 然后，我们将研究寡核苷酸与该受体的能力 它们下调银屑病患者EGF-R的体外作用 损伤。在第二个项目中，我们将尝试操作 谷胱甘肽-S转移酶pi，Gst-pi的表达 在黑色素瘤和鳞状细胞癌中过表达，可能 导致多药耐药。将测试TFOS的容量 为了选择性地首先在黑色素瘤细胞系中抑制GST-pi，随后在 皮肤转移性黑色素瘤移植到裸鼠体内。在这两种型号中，皮肤 将在应用寡核苷酸后被移除并进行检测 通过斑点杂交、Northern印迹和原位杂交检测mRNA的表达 杂交。这些研究可能会导致开发出一类新的 治疗药物，并提供对牛皮癣发病机制的洞察 以及癌症的抗药性。

A collaborative project will use single stranded synthetic DNA oligonucleotides which form triplex structures with targeted DNA regulatory regions (TFOs) to test the hypothesis that they may be used as gene-specific therapy for skin cell dysfunction. The skin is an ideal model for genetic manipulation because it can be readily evaluated and grown in vitro. Psoriasis and skin cancer will be targeted for selective manipulation. In the first project, synthetic oligonucleotide analogues will be designed to target the promoter domain of the epidermal growth factor receptor gene (EGF-R) and tested for their capacity to selectively repress EGF-R in the A431 epidermal carcinoma line which overexpressed EGF-R. Since psoriasis overexpresses EGF-R as well as TGF-alpha which binds to that receptor, we will then study the ability of oligonucleotides with in vitro effect, for their capacity to downregulate EGF-R in psoriatic lesions. In the second project, we will attempt to manipulate the expression of Glutathione-S-transferase pi, GST-pi, an enzyme which is overexpressed in melanoma and squamous cell carcinoma and which may contribute to multidrug resistance. TFOs will be tested for their capacity to selectively repress GST-pi first in melanoma lines and subsequently, in metastatic melanoma to skin implanted into nude mice. In both models, skin will be removed following application of the oligonucleotides and assayed for mRNA expression by dot hybridization, Northern blotting, and in situ hybridization. These studies may lead to the development of a new class of therapeutic agents and provide insight into the pathogenesis of psoriasis and drug resistance in cancer.