INHIBITION OF HUMAN ONCOGENE EXPRESSION BY INTERFERON

赖氨酰氧化酶的作用是抑制 Ras癌基因的表型表达。NIH 3T3小鼠细胞 经LtR-c-H-ras转化后表达极低水平的赖氨酸 氧化物酶；干扰素β介导后恢复表达 回归。反转体被赖氨酰氧化酶重新转化 反义表达载体；原代转化细胞 在转染赖氨酸氧化酶正义表达后恢复 建造。赖氨酰氧化酶转录调控序列将 被定义为研究基因在ras过程中是如何被关闭的 转化，以及干扰素逆转如何导致 恢复表达。由于反转剂的去甲基化 导致赖氨酰氧化酶表达的再转化和丧失， 控制区可能需要甲基化才能发挥活性。正性 和/或负调控蛋白结合到 转录调控序列，可能是由 无论是干扰素还是ras，都将被识别和研究。这个 赖氨酰氧化酶、胶原蛋白的可能协调调节 参与胶原合成的结构基因和酶 接下来将研究RAS的转换和恢复。 赖氨酰氧化酶在癌基因转化细胞系中的表达 也将进行研究，以揭示 行动方法或RAS与其他组织之间的相互关系 致癌基因。如果赖氨酰氧化酶活性之间存在关系 以及正常的细胞生长和行为，了解调控 该基因的作用机制可能为治疗提供机会： 可以识别出改变赖氨酰氧化酶表达的药物，并且 可能在未来，基因替代疗法可能是 考虑过了。人类癌症的细胞系，其起源于 产生胶原或弹性蛋白和赖氨酸氧化酶将被检查 赖氨酰氧化酶信息表达和酶活性的变化 以及胶原蛋白或弹性蛋白的水平。如果赖氨酰氧化酶基因 在这些人类癌症中的任何一种中，表达都降低了 使用人类赖氨酸氧化酶基因的实验将是 执行以尝试返回。赖氨酰氧化酶也被 定位于某些类型的上皮细胞。肿瘤起源于 这些组织将被检查赖氨酰氧化酶的任何变化。 表情。肿瘤来源的正常组织和细胞系 Ras癌基因突变高发的组织 还将进行检查以确定是否存在关联 赖氨酰氧化酶的表达和转化类似于 在小鼠成纤维细胞系统中可见。两国之间的关系 细胞基质中未成熟的胶原和弹性蛋白及其可能的变化 在生长促进或控制因子的结合/活性中 也将进行研究。

The enzyme lysyl oxidase functions as a suppressor of the phenotypic expression of the ras oncogene. NIH 3T3 mouse cells transformed by LTR-c-H-ras expressed very low levels of lysyl oxidase; expression was restored after interferon beta-mediated reversion. Revertants were retransformed by a lysyl oxidase antisense expression construct; the original transformed cells were reverted after transfection with a lysyl oxidase sense expression construct. Lysyl oxidase transcriptional regulatory sequences will be defined to investigate how the gene is switched off during ras transformation, and how reversion with interferon leads to the restoration of expression. Since demethylation of revertants caused retransformation and loss of lysyl oxidase expression, the control region may require methylation for activity. Positive and/or negative regulatory proteins that bind to the transcriptional regulatory control sequences, perhaps induced by either interferon or ras, will be identified and studied. The possible coordinate regulation of lysyl oxidase, collagen structural genes, and enzymes involved in collagen synthesis following ras transformation and reversion will be investigated. Lysyl oxidase expression in cell lines transformed by oncogenes other than ras will also be studied to reveal any similarities in method of action or interrelationships among ras and other oncogenes. If a relationship exists between lysyl oxidase activity and normal cell growth and behavior, understanding the regulatory mechanisms of this gene may provide opportunities for therapy: drugs that modify lysyl oxidase expression can be identified, and possibly in the future, gene replacement therapy could be considered. Cell lines of human cancers that arise from cells that produce collagen or elastin and lysyl oxidase will be examined for alterations in lysyl oxidase message expression and enzyme activity as well as collagen or elastin levels. If lysyl oxidase gene expression is decreased in any of these human cancers, expression experiments employing the human lysyl oxidase gene will be performed to attempt reversion. Lysyl oxidase has also been localized to some types of epithelia cells. Tumors arising from these tissues will be examined for any changes in lysyl oxidase expression. Normal tissue and cell lines derived from tumors of tissues that show a high incidence of mutation in the ras oncogene will also be examined to determine if there is a correlation between lysyl oxidase expression and transformation similar to that seen in the mouse fibroblast system. The relationship between immature collagen and elastin in cell matrix and possible changes in the binding/activity of growth-promoting or -controlling factors will also be studied.