A model for osseous metastasis of human breast cancer established by intrafemur injection of the MDA-MB-435 cells in nude mice.

BACKGROUND

A nude mouse model was developed and studied for temporal pathogenesis of bony metastasis of human breast cancer.

MATERIALS AND METHODS

Human breast cancer cells, MDA-MB-435, were injected into the medulla of left femurs of 10 Beige nude mice, whereas their right femurs were similarly injected with phosphate buffered saline as a control. The mice were killed at 1 week-intervals for up to 5 weeks.

RESULTS

Tumors appeared in all the animals 3 weeks after the injection: they began to appear in the medulla at 2 weeks, and invasion of the tumor into the cortex and surrounding tissues of the bone appeared at 4 weeks. Both osteolytic and osteoblastic activation frequently observed in the affected bone of breast cancer patients were present.

CONCLUSION

This model produces a high incidence of bony metastasis and may be appropriate for the study of osseous metastasis of this human disease.