Modeling Stromal Cells Inside the Tumor Microenvironment of Ovarian Cancer: In Vitro Generation of Cancer‐Associated Fibroblast‐Like Cells and Their Impact in a 3D Model

The tumor microenvironment (TME) is the combination of cells and factors that promotes tumor progression, and cancer-associated fibroblasts (CAFs) are a key component within TME. CAF originates from various stromal cells and is activated by factors such as transforming growth factor-beta (TGF-β) secreted by tumor cells, favoring chemoresistance and metastasis. Recent publications have underlined plasticity and heterogeneity and their strong contribution to the reactive stroma within the TME. Our study aimed to replicate the TME's structure by creating a 3D in vitro model of ovarian cancer (OC). By incorporating diverse tumor and stromal cells, we simulated a physiologically relevant environment for studying CAF-like cell behavior within tumor spheroids in a context-dependent manner. CAF-like cells were generated by exposing human dermal fibroblasts to OC cell line conditioned media in the presence or absence of TGF-β. Herein, we found that different stimuli induce the generation of heterogeneous populations of CAF-like cells. Notably, we observed the ability of CAF-like cells to shape the intratumoral architecture and to contribute to functional changes in tumor cell behavior. This study highlights the importance of precise assessment of CAF for potential therapeutic interventions and further provides a reliable model for investigating novel therapeutic targets in OC.