UBC Theses and Dissertations
Improving data acquisition from 3-D microtissues in image-based cancer drug screening Nasseri, Sayyed Soroush
Cell-based drug screenings are one of the early steps in the cancer drug development pipeline. New drug candidates are tested on cells related to the intended tissues to gather information about the drug efficacy, toxicity, and metabolism, in order to screen the promising drug candidates before animal and human studies. Traditionally, these screenings have been performed using tissue culture plates that grow cells on a two-dimensional surface. However, traditional drug screening methods have a high failure rate in subsequent clinical steps due to their failure to simulate the natural microenvironment of cancer cells. Three-dimensional cultures such as cancer spheroids try to address this problem by growing the cells in 3-D to mimic the in vivo conditions better, simulating the conditions such as low oxygen levels and insufficient nutrients, and including cell-cell interactions that are absent in 2-D cultures. Benefitting from 3-D cultures, while meeting the high-throughput demands of modern industrial practice requires reliance on scalable image-based techniques and developments of applicable tools for this purpose. This thesis showcases several studies using an image-based drug screening microfluidic platform capable of controlling the oxygen concentration around the cells, employing breast cancer cell spheroids. We show that spheroids can grow on-chip while monitoring them with two-photon microscopy. We have studied the effects of hypoxia on lipid nanoparticle absorption in breast cancer tumour spheroids, as well as the effects of hypoxia on cancer spheroids under chemotherapeutic treatment. This thesis also prominently presents HyClear, a novel tissue clearing protocol developed specifically for the rapid and easy application on spheroids and other microtissues, in order to enable imaging them through their depth in a high-throughput manner. HyClear was developed by adapting other tissue clearing protocols (established for larger tissues) to the needs of spheroids. The HyClear protocol was compared with other prominent tissue clearing protocols, to showcase several examples of its ability to clear small and large tissues and its applicability to large screening experiments.
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Attribution-NonCommercial-NoDerivatives 4.0 International