Profiling of cancer specific protein complexes and protein-protein interactions via single molecule technique

Abstract

Targeted therapy is that selectively inhibits proteins specifically used in cancer cells. At present, gene sequence analysis is the most widely used to predict sensitivity to targeted therapy. However, cancer cell growth is achieved by continuously changing expression levels or protein-protein interactions (PPI). Gene sequencing analysis that does not take into account the dynamics of these cellular signaling systems has limitations in predicting the susceptibility of target chemotherapy. Therefore, in order to accurately select the target anticancer drug reactivity, a diagnostic method through expression level or PPI analysis is required.The single-molecule co-immunoprecipitation (SM-coIP) technique developed to solve the above unmet needs is a quantitative analysis method by target proteins from cells or tissues in a short time. In this dissertation, the HER family proteins EGFR and HER2 will examine whether the expression level or PPI can be quantitatively measured using the single-molecule co-immunoprecipitation technique, and whether it can be used for diagnosis. In particular, the use of biomarkers based on expression level and PPI information enables predicting the sensitivity of target anticancer agents to various types of cancer, regardless of the presence or absence of genetic biomarkers. Also, it has been shown to help develop new combination treatment strategies or discover new treatment goals.In addition, this dissertation intends to deal with a barcode analysis method based on the single-molecule Förster Resonance Energy Transfer (FRET) developed to analyze protein complexes. Many proteins form multi-component complexes with other biomolecules to perform various biological processes. However, conventional biochemical methods for analyzing molecular interactions are mainly designed to detect one-to-one interactions and are generally not applicable to multi-body interactions. We show that the FRET barcode method has great potential for multiple detection of multibody biomolecule interactions through the construction and analysis of various model systems such as hybrid DNA complexes containing multiple target strands and chimeric proteins with various domains.