“Spatial SILAC—Developing Isotopic Zip Codes for Drug Development in 3D Cell Cultures”

Prof. Amanda Hummon, The Ohio State University

Abstract:

Three-dimensional cell cultures are attractive models for biological research. They combine the flexibility of cell culture with some of the spatial and molecular complexity of tissue. For example, colon cancer cell lines form spheroids, in vitro mimics of poorly vascularized tumors. The spheroids are composed of a central necrotic core, a middle quiescent layer and an outer proliferative layer of cells, similar to a rapidly growing colon tumor. Our laboratory has characterized the distribution of endogenous proteins via MALDI imaging mass spectrometry in colon spheroids and determined that the molecular gradients correlate with the pathophysiological changes in the structure. We have developed Spatial SILAC, a method to selectively label the cells in the distinct chemical microenvironments in the spheroids and assess the proteomic changes in response to drug treatment. In this presentation, the spatially-localized proteomic changes in response to the multiple kinase inhibitor Regorafenib will be described. In brief, the cellular response to Regorafenib treatment is significantly affected by the location of the cells and the chemical microenvironment.