Effect of potassium channel antagonist on proliferation in the human mammary epithelial cells MCF10A

Previous work has shown that voltage-gated potassium channels are crucial for breast cancer (e.g MCF7) cell proliferation; but the function and mechanism of these channels in proliferation of normal human mammary epithelial cells has been left largely unknown in MCF10A,so,we carry on with the study. Firstly, the effect of tetraethylammonium (TEA, a potassium channel blocker) and 4-aminopyridine (4-AP, a voltage-gated potassium channel blocker) on MCF10A cell line was detected by MTT methods. Secondly, expressions of different Kv channels, including Kv1.2, Kv1.5, were determined by blot technique. Results show that: (1)5-10mmol/L of TEA and 4-AP treatment for 72 h could significantly inhibit proliferation of MCF10A and MCF7 breast cancer cell lines; and the latter was more sensitive to both blockers. (2)Kv1.2, Kv1.5 expressed in both cell lines. The Kv1.5 protein level in MCF10A was higher than that in the MCF7 cells. These results strongly suggest that voltage-gated potassium channel-Kv1.5 may play an important physiological role in the regulation of proliferation.