Abstract A015: Multiplexed live-cell imaging for drug responses in patient-derived organoid models of endometrial cancer

Abstract

Abstract Patient-derived organoid (PDO) models of endometrial cancer are rapidly emerging as a multifunctional research model to recapitulate in vivo cancer progression and therapeutic response. PDO models are generated by reconstituting patient tumor cells in extracellular basement membrane extract (BME) and culturing as three-dimensional domes supplemented with a specialized niche of growth factors. Despite the rise in popularity of PDO models to assess drug response in vitro, there are limited commercially available reagents that are compatible with BME. In addition, most reagents are endpoint assays that require cell lysis, which is problematic because PDOs are a limited resource. Reducing drug response assessment to a single timepoint misses out on valuable kinetic response data, and samples cannot be used for subsequent downstream analyses, such as RNA sequencing or protein assays. Herein we describe a method to assess drug effects in PDO models using kinetic live-cell imaging. Live-cell imaging is a sophisticated form of automated microscopy that, when combined with fluorescent dyes, has the capacity to quantify multiple cellular responses simultaneously. Importantly, live-cell imaging reagents do not perturb cell viability or induce DNA damage, thereby allowing for accurate repeated assessment of PDO response to treatment over time. In proof-of-concept studies, we first established the utility of this approach to assess the effect of cytotoxic and cytostatic agents in PDO models of endometrial cancer. Specific parameters of interest include PDO number, area, cell health and induction of apoptosis. Agents that produced a cytotoxic effect promoted a decrease in organoid area and number over time, concomitant with an increase in apoptosis as measured by Annexin V staining. Ongoing studies are examining the dose-dependent phenotypic effects of cytostatic agents such as progestins in endometrial cancer PDO models. To evaluate the safety of the compounds, we have also conducted experiments using patient-derived organoids of normal endometrium, which was collected from uninvolved regions of the uterus in cytoreductive surgery. We envision that this automated kinetic imaging platform can be expanded to other phenotypic readouts to better understand diverse therapeutic effects of different classes of drugs under investigation for endometrial cancer. Citation Format: Kaitriana E. Colling, Emily L. Symons, Hiruni K. Sumanasiri, Kristina W. Thiel. Multiplexed live-cell imaging for drug responses in patient-derived organoid models of endometrial cancer [abstract]. In: Proceedings of the AACR Special Conference on Endometrial Cancer: Transforming Care through Science; 2023 Nov 16-18; Boston, Massachusetts. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(5_Suppl):Abstract nr A015.