【Animal Modeling】-Establishment of gastric cancer metastasis model based on clinical tumor specimens

  Objective: To establish a gastric cancer metastasis model based on clinical tumor specimens, and to provide individualized animal models for gastric cancer metastasis research.

  Methods: Fresh surgical specimens of gastric cancer were transplanted under the skin of nude mice to establish a patient-derived xenograft (PDX) model of gastric cancer patients. The subcutaneous tumor tissue was further transplanted into the muscular layer of the stomach of nude mice by surgery, and the nude mice were continuously observed. The physical status of the mouse was detected by near-infrared fluorescence in vivo imaging technology to detect the occurrence of tumor metastasis. The tumor-bearing mice were dissected, and the lung metastases were further transplanted subcutaneously into nude mice to obtain solid tumors. HE staining to observe the structural characteristics of primary tumors and metastatic tumors ,(short tandem repeat) STR analyzes the genetic characteristics of primary tumors and metastases. PCR-Array analyzes the expression of metastasis-related genes in metastases and primary tumors.

  Results: The PDX model of gastric cancer was successfully established, and the tissue structure of the transplanted tumor was basically the same as that of the patient; the mouse with the number C19751 was found to have lung and liver metastasis through orthotopic gastric transplantation. Among them, the lung metastasis obtained a solid tumor after subcutaneous transplantation, STR The analysis showed that the primary tumor maintained the same genetic characteristics as the lung metastases. PCR-Array results showed that compared with the primary tumor, the expression of CXCL12, IGF1 and MMP2 genes were significantly up-regulated in the metastatic tumor.

  Conclusion: The successful establishment of a gastric cancer metastasis model using clinical tumor specimens provides a good individualized model for gastric cancer metastasis research.