Establishment and characterization of patient-derived tumor xenograft using gastroscopic biopsies in gastric cancer.

Abstract

68 Background: The patient-derived tumor xenograft (PDTX) model has become the most realistic model for preclinical studies. PDTX models of gastric cancer using surgical tissues are reported occasionally; however, the PDTX model using gastroscopic biopsy, which is presented in this study, is very rare. Methods: A total of 185 fresh gastroscopic biopsies of gastric cancer were subcutaneously transplanted into NOD/SCID (Nonobese Diabetic/Severe Combined Immunodeficiency) mice. The characteristics of PDTX were identified by hematoxylin and eosin (H&E) staining, immunohistochemistry (IHC), dual-color in-situ hybridization (DISH), and targeted next-generation sequencing. Chemosensitivity of PDTX model was tested using chemotherapy regimens based on patients. Results: Sixty-three PDTX models were successfully established (34.1%, 63/185) and passaged to maintain tumors in vivo, and the mean latency period of xenografts was 65.86±32.84 days (11-160 days). Biopsies of prior chemotherapy had a higher transplantation rate (52.1%, 37/71) than biopsies after chemotherapy (21.9%, 25/114; P<0.01). No differences were found between the latency period of xenografts and characteristics of patients. The pathological and molecular features of PDTX as well as chemosensitivity were highly consistent with those of primary tumors of patients. The genetic characteristics were stable during passaging of PDTX models. Conclusions: PDTX models using gastroscopic biopsies in gastric cancer were demonstrated for the first time, and the biological characteristics of the PDTX models were highly consistent with patients, which provided the best preclinical study platform for gastric cancer. [Table: see text]