Bioprinted colorectal cancer organoids as a platform for large-scale therapeutic screening

Colorectal cancer is the fourth leading cause of cancer-related deaths in the United States. Among patients with metastatic colorectal cancer, approximately 70-75% survive more than 1 year after diagnosis, 30-35% survive more than 3 years, and fewer than 20% survive beyond 5 years. The main treatment options for unresectable metastatic colorectal cancer include cytotoxic chemotherapy, biologics, immunotherapy, and combinations thereof. Therapeutic options for unresectable metastatic disease remain limited, and more predictive preclinical platforms are urgently needed. To address this need, we developed a high-throughput mini-ring screening platform using patient-derived colorectal cancer organoids generated through 3D bioprinting. We generated and screened more than 28,000 bioprinted organoid mini-rings to ensure uniform size, architecture, and reproducibility across models.Screens incorporated standard colorectal cancer agents, including 5-fluorouracil, capecitabine, irinotecan, leucovorin, and oxaliplatin, along with a targeted 100-compound targeted panel spanning diverse pathways. Dose-response profiling enabled robust IC50 determination and revealed distinct sensitivity and resistance patterns across organoid models representing multiple disease stages. Transcriptomic analyses for each model were integrated to contextualize these functional profiles and identify pathway-level features associated with therapeutic vulnerability.This work shows how bioprinted colorectal cancer organoids provide a scalable and biologically relevant platform for high-throughput drug screening to support the development of more precise and effective therapeutic strategies for colorectal cancer.