Figure 1.

(A) Chemical structure of VCE-006.1. (B) VCE-006.1 and LPI induces ERK1/2 activation in DU145 cells. The cells were stimulated as indicated and the expression of phospho-ERK1/2 and total ERK1/2 determined by immunoblots. (C) VCE-006.1 and LPI induces [Ca²⁺] immobilization in U937 cells. U937 cells were loaded with Indo1-AM, treated with the compounds, and the calcium mobilization was measured by ratiometric fluorescence as indicated under Materials and Methods. (D) GPR55 activity of VCE-006.1 at different concentrations (1, 5, and 10 µM) in the absence or the presence of 10 µM LPI on HEK293T-GPR55-CRE-luc cells. Results are expressed as the fold induction of GPR55 activity and represent means ± SEM of data generated in 6 independent experiments, each conducted in triplicates. Statistical significance was determined by one-way ANOVA followed by the Tukey test (* p < 0.05, ** p < 0.01, *** p < 0.005 vs. control (basal) and VCE-006.1 alone; ^# p < 0.05 vs. LPI and VCE-006.1 (1 µM) + LPI).