Orthotopic transplantation of human brain tumor tissues in nude mice and analysis of the parental characteristics of the xenografts

Abstract

Objective To establish a method for direct orthotopic transplantation of human brain tumors into mouse brain and assess the parental characteristics of the xenografts. Methods Fresh tissues of human brain metastasis of lung adenocarcinoma and glioblastoma tissues subcutaneously implanted in nude mice were harvested and minced into pieces. A special trochar was used to inject the tissue pieces into the right caudate nuclei of nude mice through the burr hole in the mouse skull. The efficiency of tumorigenicity, survival time of tumor-bearing mice, histopathological features, expressions of tumor markers in the xenografts and MRI findings were observed. Results The metastatic lung adenocarcinoma and glioma xenografts were passaged for 6 and 13 generations in nude mice, and the average survival time of the tumor-bearing mice was 38.0±0.9 days and 19.0±1.3 days, respectively. The metastatic xenogratts were characterized by expressions of CEA and acid mucin without invasiveness to the normal recipient brain tissue, which were consistent with the features of the parental metastatic tumor. The glioma xenogratts exhibited deep invasiveness to the normal recipient brain tissue and high expression of EGFR, which were identical to the characteristics of the parental tumor. Conclusion Compared with stereotactic cell suspension injection, direct tumor tissue graft injection requires simple procedures and well maintains the characteristics of the parental tumor tissue in the xenograft in nude mice. This method well suits the purposes of establishing orthotopic xenotransplantation models of brain tumors in nude mice. Key words: Brain tumor; Orthotopic implantation; Pathology; Nude mice