Transferrin receptors in cultured breast cancer cells.

Transferrin receptors were demonstrated on the cell membrane of breast cancer epithelial cells in primary or long-term culture. Diferric transferrin binding was saturable, specific and was not related to DNA content or clinical and histological features of the tumour. However a good correlation (p less than 0.01) was found between transferrin binding and thymidine incorporation. These results suggest the possibility of transferrin receptor measurement as a reflection of the proliferative activity of cultured breast tumour cells.