Exploiting the Novel Repressed Transactivator Assay to Identify Protein Peptide Inhibitors of the Myc Oncoprotein

摘要

Fundamental research clearly shows that the product of the c-myc oncogene is often expressed at elevated levels in a large number of breast cancers and is associated with poor prognosis, high-risk disease for further detail, see our recent review (3). Indeed, Myc drives cell proliferation and can initiate as well as contribute to tumor development, as confirmed by both in vitro and in vivo models of breast cancer. The highly conserved regions of the Myc protein are thought to participate in protein:protein interactions. Importantly, blocking these sites can effectively inhibit Myc function and block breast carcinoma cell growth. Thus, Myc is a valid target for the development of novel therapeutics to inhibit mammary cells of malignant transformations in a specific and sensitive manner. This is the primary goal of this proposal. To achieve our goal, we are using the novel Repressed Transactivator (RTA) assay developed in collaboration with our lab (1). The RTA is an in vivo functional assay that will enable Myc-binding proteins and inhibitors of Myc:protein interactions to be identified and characterized. This experimental tool is conceptually similar to the conventional 'two-hybrid' technology but offers significant improvement. First, the RTA allows transactivator bait proteins like Myc, to be used in a two-hybrid approach to clone novel interactors. Second, the ability of the RTA to identify inhibitors of a given protein:protein interaction makes it particularly well suited for high throughput screening of protein:protein interactions and the identification of inhibitor compounds.