TY - GEN N2 - During healthy development and aging, somatic mutations aggregate in tissues, lending different mutational profiles to cells within these tissues. Similarly, developmental processes create the functional diversity necessary for normal tissue function. Cancer arises from the aberrant functioning of these processes. Mutational profiles and epigenetic regulation support uncontrolled growth of neoplasms with the potential ability to invade nearby tissues. The resulting intra-tumor heterogeneity contributes to evasion of drug pressures via Darwinian selection, and cell-state plasticity allows for dynamic shifts in regulation into drug-resistant persistor states. While bulk genomic assays profile averages of sampled cell populations, single-cell approaches allow for a picture of the heterogeneity of healthy and diseased complex tissues. In this dissertation, I assess the state of the single-cell field with a focus on assays characterizing whole genome copy number variation and chromatin accessibility. I show three examples of profiling heterogeneity by (i) assessing the genomes of thousands of cells in healthy and diseased tissues (ii) mapping the chromatin landscape of the murine hippocampus, and (iii) characterizing the development of Trametinib resistance through cell state plasticity across basal-like triple negative breast cancer cell lines. DO - 10.6083/fb4948977 DO - DOI AB - During healthy development and aging, somatic mutations aggregate in tissues, lending different mutational profiles to cells within these tissues. Similarly, developmental processes create the functional diversity necessary for normal tissue function. Cancer arises from the aberrant functioning of these processes. Mutational profiles and epigenetic regulation support uncontrolled growth of neoplasms with the potential ability to invade nearby tissues. The resulting intra-tumor heterogeneity contributes to evasion of drug pressures via Darwinian selection, and cell-state plasticity allows for dynamic shifts in regulation into drug-resistant persistor states. While bulk genomic assays profile averages of sampled cell populations, single-cell approaches allow for a picture of the heterogeneity of healthy and diseased complex tissues. In this dissertation, I assess the state of the single-cell field with a focus on assays characterizing whole genome copy number variation and chromatin accessibility. I show three examples of profiling heterogeneity by (i) assessing the genomes of thousands of cells in healthy and diseased tissues (ii) mapping the chromatin landscape of the murine hippocampus, and (iii) characterizing the development of Trametinib resistance through cell state plasticity across basal-like triple negative breast cancer cell lines. T1 - Single-cell approaches for deciphering complex tissue heterogeneity DA - 2020 AU - Törkenczy, Kristóf A. L1 - https://digitalcollections.ohsu.edu/record/8696/files/Torkenczy.Kristof.2020.pdf PB - Oregon Health and Science University PY - 2020 ID - 8696 L4 - https://digitalcollections.ohsu.edu/record/8696/files/Torkenczy.Kristof.2020.pdf KW - DNA Copy Number Variations KW - Hippocampus KW - Epigenomics KW - Breast Neoplasms KW - trametinib TI - Single-cell approaches for deciphering complex tissue heterogeneity Y1 - 2020 L2 - https://digitalcollections.ohsu.edu/record/8696/files/Torkenczy.Kristof.2020.pdf LK - https://digitalcollections.ohsu.edu/record/8696/files/Torkenczy.Kristof.2020.pdf UR - https://digitalcollections.ohsu.edu/record/8696/files/Torkenczy.Kristof.2020.pdf ER -