A study on human breast carcinoma xenografts in nude mice

Objective To study the spontaneous metastasis and the genetic stability of human breast carcinoma xenografts in nude mice and its micrometastasis. Methods The intact tissue of surgical specimens from breast carcinoma were xenografted into nude mice and transplanted from generation to generation. Cells from the xenografts were cultured in vitro and retransplanted into nude mice. Microsatellite DNA in genome of human breast carcinoma, xenotransplanted tumors and metastases in nude mice were analysed at three microsatellite loci. Results The tumorigenicity of orthotopic xenotransplantation was 88.6%(31/35) with a metastasis rate of 41.9%(13/31). Cells from the xenografts were cultured in vitro successfully, both the take rate of retransplantation into nude mice and the spontaneous lung metastasis rate were 100%(10/10). Microsatellite DNA sequences in genome of the xenotransplanted tumors and metastases in nude mice were identical with that of the original human breast carcinoma at the three microsatellite loci. Conclusions The tumorigenicity and metastasis potential can be improved in human breast carcinoma xenograft using the intact fresh tumor tissue and orthotopic graft. The xenotransplanted tumors and their passaged tumors maintained the genetic stability.The detection of microsatellite DNA may discover micrometastasis in the nude mice model.