Abstract P37: Establishment of Gastric Organoids Biobank and Its Usage

Abstract Gastric cancer is highly heterogeneous. To analyze their biology, patient-derived organoids (PDOs) are useful because they maintain intra-tumor heterogeneity (ITH) as well as inter-patient heterogeneity. Recently, four groups reported the establishment of gastric PDOs. However, it is still not easy because of the need to overcome a common problem: “contamination” of the culture with “non-cancer cell”-derived organoids from the specimen. These non-cancer organoids often overgrow and became dominant. Furthermore, PDOs have another limitation. They contain only epithelial cells and no other types of cells, making it difficult to study the tumor microenvironment (TME). Since October 2021, we have been working on establishing our own gastric PDO biobank. 63 gastric PDOs have been successfully established from 24 patients. Cancer organoids are enriched by manual selection under a microscopy. Our biobank contains 35 gastric cancer PDOs, 16 of which were confirmed as cancer using WES and WTS. Profiling for the remaining PDOs is ongoing. 12 fibroblasts and 26 cancer associated fibroblasts (CAFs) have also been successfully established. To overcome the difficulties of TME research with PDOs, co-culture platform for PDOs and fibroblasts has been established. This co-culture platform can provide new insights into the functions of CAFs, one of the major components of TME. In this poster, I will describe the progress of our gastric PDO biobank establishment and the prospects for my projects using it. Citation Format: Takeshi Hagihara, Kie Kyon Huang, Raghav Sundar, Tomoyuki Uchihara, Clara Shi Ya Ng, Su Ting Tay, Angie Lay Keng Tan, Jimmy Bok Yan So, Patrick Tan. Establishment of Gastric Organoids Biobank and Its Usage [abstract]. In: Proceedings of Frontiers in Cancer Science; 2023 Nov 6-8; Singapore. Philadelphia (PA): AACR; Cancer Res 2024;84(8_Suppl):Abstract nr P37.