Tracking cells in epithelial acini by light sheet microscopy reveals proximity effects in breast cancer initiation

Abstract

Cancer clone evolution takes place within tissue ecosystem habitats. But, how exactly tumors arise from a few malignant cells within an intact epithelium is a central, yet unanswered question. This is mainly due to the inaccessibility of this process to longitudinal imaging together with a lack of systems that model the progression of a fraction of transformed cells within a tissue. Here, we developed a new methodology based on primary mouse mammary epithelial acini, where oncogenes can be switched on in single cells within an otherwise normal epithelial cell layer. We combine this stochastic breast tumor induction model with inverted light-sheet imaging to study single-cell behavior for up to four days and analyze cell fates utilizing a newly developed image-data analysis workflow. The power of this integrated approach is illustrated by us finding that small local clusters of transformed cells form tumors while isolated transformed cells do not.

BigDataProcessor2: A free and open-source Fiji plugin for inspection and processing of TB sized image data

“…As big image data is becoming increasingly prevalent we are positive that the already existing user base (e.g. Alladin et al 2020, Villani et al 2019, Wolny et al 2020 will grow even further in the future. Supplementary Figure 4: Screenshot of the Open menu.…”

Multiscale light-sheet organoid imaging framework

“…Although with high degree of accessibility, performing live imaging of organoid growth remains a challenge, as it typically requires not only microscopy techniques capable of stable long-term imaging of several samples simultaneously, but also dedicated analysis and processing pipelines that can cope with complex imaging data. Nonetheless, previous work on the live recording of organoid dynamics has focused either on specific biological questions 6,8,9 or on specific isolated tools 10 without a more generalised yet in-depth approach on light-sheet imaging and data analysis. The only current work which aimed at creating a light-sheet organoid imaging platform 11 focused mainly on the determination of culture-wide heterogeneities through a combination of both light-sheet and wide-field techniques.…”

Cell Tracking for Organoids: Lessons From Developmental Biology

“…For organoids, this approach is increasingly feasible, especially given recent progress in CRISPR based techniques that allow fluorescent reporters to be directly incorporated in organoid lines ( Artegiani et al, 2020 ). An organoid model for breast cancer has been used to study why some cells carrying an oncogenic mutation become highly proliferative while others do not ( Alladin et al, 2020 ). Tracked lineages and a fluorescent reporter for the mutation indicated that the local density of mutated cells was the most predictive feature.…”