Involvement of a novel fast inward sodium current in the invasion capacity of a breast cancer cell line.
This work reports the finding of a unique fast inward sodium current (I(Na)) in MDA-MB-231 cells which is missing in MDA-MB-468 cells and in MCF-7 cells. This current is high-voltage-activated and displays a window current at the membrane potential of MDA-MB-231 cells. This current is blocked by high concentrations of tetrodotoxin (TTX). In MDA-MB-231 cells, which are the most invasive cells among the three cell lines tested, proliferation and migration were not sensitive to TTX while invasion was reduced by approximately 30%. These experiments suggest that I(Na) is involved in the invasion process, probably through its participation to the regulation of the intracellular sodium homeostasis.
Roger
Sébastien
S
Nutrition, Croissance et Cancer, Inserm Emi-U 0211, Faculté de Médecine, 2 Bd Tonnellé, 37032 Tours Cedex, France.
Besson
Pierre
P
Le Guennec
Jean-Yves
JY
D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D009361:Neoplasm Invasiveness; D012964:Sodium / Q000378:metabolism; D015222:Sodium Channels / Q000502:physiology*; D013779:Tetrodotoxin / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D015222:Sodium Channels; D013779:Tetrodotoxin; D012964:Sodium