Figure 1. Establishment of patient-derived xenograft (PDX) by the samples from Tochigi Cancer Center.

(a) Samples from patients are gathered after obtaining written informed consent. (b) Specimens are immediately soaked into sample preservation media and transported to Kumamoto University by transport delivery service at 4°C. (c) The specimens were cut into approximately 5-mm³ pieces and transplanted into both 6 to 8-week-old BRJ mice flanks. (d) Mice were observed weekly for health conditions and tumor growth, and tumor passage was conducted when the tumor size reached more than 1 cm in diameter. Removed tumors were cut into 5-mm3 and passaged for the next generation, and the rest of the tumors were stored for re-transplantation in freezing media (Bambanker, NIPPON Genetics, Tokyo, Japan) at a liquid nitrogen tank and for the preparation of samples for pathological blocks and fresh frozen samples.