An Ex Vivo Mini-Tumor Culture Protocol for Evaluating Individualized Efficacy of Chemotherapy and Immunotherapy.

Conventional drug screening models face a series of challenges in guiding individualized cancer treatment, including time-consuming processes, limited drug coverage, and insufficient accuracy in efficacy evaluation. This study aims to establish a convenient, rapid, and reliable drug screening protocol for evaluating individualized efficacy of chemotherapy and immunotherapy. We established an ex vivo mini-tumor culture platform by culturing tumor fragments in an air-liquid interface system, which was capable of sustaining tumor growth for at least 2 weeks and maintaining immune cell infiltration for over 1 week. Using this mini-tumor culture platform, we can evaluate the individualized therapeutic responses of different tumors to chemotherapy and immunotherapy, including gemcitabine, 5-fluorouracil, cisplatin, αPD-1 and αPD-L1. Furthermore, using this drug evaluation platform, we revealed distinct therapeutic responses to immunotherapy between immune-cold tumors and immune-hot tumors, and demonstrated the important role of the immunologic adjuvant resiquimod (R848) in enhancing immunotherapy efficacy. This mini-tumor culture protocol provides a feasible implementation approach for ex vivo personalized drug testing.