Fig. 4

The effect of E2 and the 2′,3′,4′-THC/E2 combination on transcription are ERα-dependent. A U2OS cells were transfected with NKG2E-TK-Luc without or with an expression vector for ERα. The cells were treated with 10 nM E2, 5 μM 2′,3′,4′-THC alone or in combination for 24 h and then luciferase activity was measured. B, C U2OS-ERα cells were maintained in the absence or presence of 1 µg/ml doxycycline to induce ERα for 24 h and then were treated with 10 nM E2, 5 μM 2′,3′,4′-THC alone or in combination for 24 h. B KRT19 and C FGR mRNA levels were measured by qRT-PCR. GAPDH was used as a reference gene to calculate fold change. D The GPER1 antagonist G-15 had no effect on the activation of NKG2E-TK-Luc. U2OS cells were transfected with NKG2E-TK-Luc and an expression vector for ERα. The cells were treated with 10 nM E2, 5 μM 2′,3′,4′-THC alone or in combination for 24 h in the absence and presence of 1 μM G-15, and then luciferase activity was measured. E, F U2OS-ERα cells were treated with 10 nM E2, 5 μM 2′,3′,4′-THC alone or in combination for 24 h in the absence and presence of 1 μM G-15. E KRT19 and F FGR mRNA levels were measured by qRT-PCR. The data are mean of triplicate samples ± SD. The statistical significance was determined by one-way ANOVA followed by Tukey’s multiple comparisons post hoc test