Abstract 3144: Intratumor heterogeneity quantification using 3D segmentation of organoids co-culture systems

Abstract

Intratumoral heterogeneity is an essential aspect of cancer biology, as the diversity of cancer cells can increase challenges of designing effective treatment. Cancer cells within the same tumor evolve and compete for shared resources and may also respond differently to drug treatments. In previous work, by closely analyzing triple negative breast cancer xenografts, we have identified a system of closely-related subclonal populations within a tumor that respond differentially to chemotherapy. To explore the dynamics of competition and cooperation between these subclones, we derived cell lines from each and tagged them with fluorescent markers. We then co-cultured these cell lines in 3D organoids and tracked them using Opera Phenix high content screening system (3D confocal fluorescence microscopy). To determine the number of cells and the location of each subclones within organoids, we developed a 3D cell segmentation pipeline. Our pipeline relies on a two-step process where organoids are segmented first and then individual cells are detected within each organoid. Preliminary analysis of hundreds of organoids suggests that the two cell types preserve their relative ratio and sensitivity to treatment regardless of organoid size, suggesting that the system is in a state of ecological coexistence. We will present results on cellular mixing during growth and treatment and the implications for adaptive therapy ecologies in tumors. Citation Format: Patience Mukashyaka, Javad Noorbakhsh, Pooja Kumar, Elise Courtois, Olga Anczukow, Paul Robson, Edson Liu, Jeffrey Chuang. Intratumor heterogeneity quantification using 3D segmentation of organoids co-culture systems [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 3144.