Characterization of a renal cell carcinoma cell line derived from a human bone metastasis and establishment of an experimental nude mouse model.

PURPOSE

We provide the necessary tools to study the biology of bone metastasis using renal cell carcinoma as a model. A relevant renal cell carcinoma cell line developed from a human bone metastasis is described and an experimental model in the nude mouse was established.

MATERIALS AND METHODS

The novel cell line RBM1 was developed from bone metastasis from a patient with renal cell carcinoma. In vitro methods used to study the cell line included karyotype analysis, reverse-transcriptase polymerase chain reaction, ribonuclease protection assay and Western blot analysis. An intratibial injection model in the nude mouse resulted in bone lesions similar to those in human patients.

RESULTS

Chromosomal analysis of this cell line revealed characteristic cytogenetic abnormalities common in renal cell carcinoma. RBM1 cells expressed parathyroid hormone parathyroid hormone related peptide, interleukin-6 and macrophage colony-stimulating factor, which are cytokines involved in osteoclast activation and subsequent bone resorption. Western blot analysis revealed the presence of high levels of epidermal growth factor receptor and c-MET. Reproducible osteolytic lesions developed in the nude mouse after injecting 1 x 106 cells into the tibia.

CONCLUSIONS

This cell line and animal model may allow further study of the biology and mechanism of renal cell carcinoma bone metastasis.