Session 4 : Molecular mechanisms of resistance

Advanced microscopy methods for the study of breast cancer

One in seven women will contract breast cancer during the course of their lives. Triple-negative breast cancer (TNBC) is the most aggressive form of breast cancer and results in a dramatic decrease in survival rate due to its resistance to chemotherapy and propensity to metastasize. Chemoresistance and metastasis are characterized by high levels of heterogeneity and plasticity of cellular phenotypes, making it difficult to study these mechanisms and design therapies to eliminate the tumor. In particular, the difficulty to follow the evolution of breast cancer phenotypes as a function of time has hindered our understanding of these therapy escape mechanisms as well as our ability to counteract them.

Our approach is based on combining state-of-the-art techniques from a number of different disciplines, including chemistry (organelle-targeting, environment-sensitive fluorescent dyes), physics (spectral emission and fluorescence lifetime imaging, spectral encoding), computer science (high-dimensional phenotyping, dimensionality reduction, clustering) and biology (3D tumor spheroids), merging them to cohesively work together.

Here, I will present our technological advancement in fluorescence microscopy aimed at studying in detail not only the properties that characterize cancerous cells but also the transitions that the cells exploit to escape therapy. Indeed, during the past five years, we have developed a number of technological advancements (Scipioni et al, Nat.Meth. 2021, Yao, Brennan, Scipioni et al., Nat.Meth.2022, Scipioni, Tedeschi et al, BioRxiv 2024a) and biological systems (Tedeschi, Scipioni et al, BioRxiv 2024b) that allow for the study of the evolution of TNBC in response to exposure the chemotherapy and to changes in environmental conditions.