Protocol on utilizing murine gastric cancer organoids for modeling subcutaneous, orthotopic primary, and liver metastatic disease in mice.

Tumor initiation, growth, and spread are influenced by cancer cell intrinsic and tissue microenvironment factors of the organ the tumor resides in. Here, we provide a protocol on utilizing murine gastric cancer (GC) organoids as transplantable mouse models for subcutaneous, orthotopic primary, and liver metastatic disease. We provide detailed instructions for organoid expansion; processing of GC organoids; and their subsequent subcutaneous, intra-stomach wall, and intra-splenic transplantation. We then detail steps for post-procedure tumor and metastasis monitoring and outcomes. For complete details on the use and execution of this protocol, please refer to Huber et al.(1).