Targeting CAFs-Mediated Stromal Signaling in a Patient-Derived Organotypic Colorectal Tumor Model.

Colorectal cancer, a significant cause of cancer-related mortality, often exhibits drug resistance, highlighting the need for improved tumor models to advance personalized drug testing and precision therapy. We generated organoids from primary colorectal cancer cells cultured through the conditional reprogramming technique, establishing a framework to perform short-term drug testing studies on patient-derived cells. To model interactions with stromal cells in the tumor microenvironment, we combined cancer cell organoids with carcinoma-associated fibroblasts (CAFs), a cell type implicated in disease progression and drug resistance. Our organotypic models revealed that CAFs promote cancer cell proliferation and stemness primarily through HGF-MET paracrine signaling and activation of Cyclin-Dependent Kinases (CDKs). Disrupting these tumor-stromal interactions reduced organoid size while limiting oncogenic signals and cancer stemness. Leveraging this tumor model, we identified effective drug combinations targeting colorectal cancer cells and their tumorigenic activities. Our study highlights a path to incorporate patient-derived cells and tumor-stromal interactions into a drug testing workflow that could identify effective therapies for individual patients.