Establishment and Characterization of a Human Gastrointestinal Stromal Tumour (GIST) Xenograft in Athymic Nude Mice

Background: The majority of gastrointestinal stromal tumours (GISTs) contain oncogenic KIT (v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog) or platelet-derived growth factor-alpha (PDGFRA) receptor tyrosine kinase (TK) mutations and are initially, but only temporarily sensitive to TK inhibitors. The aim of this study was to establish and characterize a human GIST xenograft that could be used for evaluating various molecularly targeted therapies. Materials and Methods: GIST tissue from four patients was implanted under the skin of athymic nude mice. In one case a tumour line was established. Results: The xenograft showed characteristic GIST morphology and exhibited the same mutation profile as that of the patient. Conclusion: A human GIST xenograft with mutation in KIT exons 11 and 17 has been established and maintained in nude mice for 3 years (13 passages). This model will enable further studies on mechanisms of resistance, combination therapies and allow testing of novel targeted therapies.