Voltage-gated K+ (Kv) channels have been considered to be a regulator of membrane potential and neuronal excitability. Recently, accumulated evidence has indicated that several Kv channel subtypes contribute to the control of cell proliferation in various types of cells and are worth noting as potential emerging molecular targets of cancer therapy. In the present study, we investigated the effects of the Kv1.1-specific blocker, dendrotoxin-kappa (DTX-kappa), on tumor formation induced by the human lung adenocarcinoma cell line A549 in a xenograft model. Kv1.1 mRNA and protein was expressed in A549 cells and the blockade of Kv1.1 by DTX-kappa, reduced tumor formation in nude mice. Furthermore, treatment with DTX-kappa significantly increased protein expression of p21Waf1/Cip1, p27Kip1, and p15INK4B and significantly decreased protein expression of cyclin D3 in tumor tissues compared to the control. These results suggest that DTX-kappa has anti-tumor effects in A549 cells through the pathway governing G1-S transition.
Adenocarcinoma/drug therapy/genetics/pathology ; Animals ; Cell Line, Tumor ; Cell Proliferation/drug effects ; Disease Models, Animal ; Elapid Venoms/*pharmacology ; Elapidae ; Humans ; Kv1.1 Potassium Channel/*antagonists & inhibitors/deficiency/genetics/metabolism ; Lung Neoplasms/*drug therapy/genetics/pathology ; Mice ; Mice, Nude ; Neoplasm Transplantation ; Potassium Channel Blockers/*pharmacology ; RNA, Messenger/genetics ; Transplantation, Heterologous