Figure 3

TRPM8 mRNA expression is under hormonal control. (A) Upper panel: agarose gel showing TRPM8 mRNA expression in MCF-7 cells which were incubated in steroid-free FCS medium (DCCFCS) for 24, 48 and 72 h. Lower panel: histogram showing a decrease of TRPM8 mRNA expression in DCCFCS medium (*, p < 0.05, three independent experiments). (B. a) Upper panel: a representative experiment showing TRPM8 mRNA expression in MCF-7 cells which were incubated in DCCFCS medium for 48 h prior to E₂ (10 nM) application for 24 and 48 h. Lower panel: histogram showing that E₂ increased TRPM8 mRNA expression (*, p < 0.05, **, p < 0.01, four independent experiments). (B. b) Upper panel shows an agarose gel representative of the effect of E₂ on TRPM8 expression. MCF-7 cells were growing in 0FCS medium for 48 h prior to added E₂ (10 nM) for 24 h and 48 h. Lower panel: histogram showing that E₂ increased TRPM8 mRNA levels (*, p < 0.05, three independent experiments). TRPM8 mRNA levels are expressed as the ratio of TRPM8 on β-actin referent gene. (C) Histograms showing the average of cells sensitive to Icilin (left panel) and the average of the amplitude of Icilin-induced Ca²⁺ entry (right panel) in MCF-7 cells -incubated in 0FCS for 48 h prior to E₂ (10 nM) application for 24 and 48 h (***, p < 0.001, three independent experiments).