Inhibition of cell growth and telomerase activity of breast cancer cells in vitro by 3'-azido-3'-deoxythymidine.

The effect of zidovudine (3'-azido-3'-deoxythymidine; AZT) was investigated in four breast cancer cell lines, a T4 cell leukemia, and a normal breast cell line in vitro. AZT inhibited the growth of all tumoral cell lines, but it did so in a wide range of concentrations. The growth of a normal breast cell line was also inhibited, although it required a much higher concentration. Furthermore, AZT inhibited colony formation in soft agar and telomerase activity. These results indicated that AZT can be potentially used, alone or in combination, as an anti-breast cancer agent.