Comparative Roles of Overexpressed and Mutated H- and K-ras in MammaryCarcinogenesis

摘要

The objective of this study was to characterize events in the uniformly selectiveassociation of H-ras gene activation, but not K-ras gene activation, in the rat mammary carcinogenesis model. Three primary objectives were investigated. First, the relative tumorigenic potency of activated H-ras and K-ras-2B was investigated. The activated H-ras gene was found to be approximately 10-fold more potent at inducing mammary tumors than the activated K-ras gene. Yet, the K-ras oncogene was still effective at mammary carcinoma induction. Second, the relative percentage of mammary transplants with mutations in H-ras and K-ras was investigated. This objective will be completed soon, but, as yet, no data is available. The third objective was to investigate the role of H-ras regulatory elements in rat mammary tumorigenesis using transgenic rats harboring a H-ras gene (HrHr transgenics) or K-ras gene (HrKr transgenics) controlled by H-ras gene regulatory elements.