Differential expression of voltage‐activated Na+ currents in two prostatic tumour cell lines: contribution to invasiveness in vitro

Abstract

The voltage‐gated ionic currents of two rodent prostatic cancer cell lines were investigated using the whole‐cell patch clamp technique. The highly metastatic Mat‐Ly‐Lu cells expressed a transient, inward Na⁺ current (blocked by 600 nM tetrodotoxin), which was not found in any of the weakly metastatic AT‐2 cells. Although both cell lines expressed a sustained, outward K⁺ current, this occurred at a significantly higher density in the AT‐2 than in the Mat‐Ly‐Lu cells. Incubation of the Mat‐Ly‐Lu cell line with 600 nM tetrodotoxin significantly reduced the invasive capacity of the cells in vitro. Under identical conditions, tetrodotoxin had no effect on the invasiveness of the AT‐2 cells.