Figure 5.

Effect of cannabinoids on intracellular Ca²⁺ and ROS in prostate carcinoma cells. (A) Typical dose-dependent effects for cannabinoids on intracellular Ca²⁺ in PCCs, with either efficacy or potency being higher in cells serum-deprived (SDP) for 24 h. The effect of CBG in LNCaP and DU-145 cells is shown. See Table S6 for the full data in the four PCCs with CBD, CBG and CBC. (B,C) Involvement of ROS in the effect of CBD on different PCCs. Time course of ROS production by PCC cells as measured by spectrofluorometric analysis as described in Methods. Fluorescence detection was carried out after the incubation of either 100 µM H₂O₂ or CBD (10 µM) at different times (0–30–60–120 min) in cells grown in normal medium (B) or in cells kept without serum prior to treatment (C). The fluorescence measured at time 0 was considered as basal ROS production and subtracted from the fluorescence at different times (Δ1). Data are reported as Δ2 (i.e. Δ1 values at different doses minus the Δ1 values of cells incubated with vehicle), and are mean ± SEM of at least n= 3 experiments. Note how the effect of both CBD and H₂O₂ becomes significant only in the absence of serum (C) and only in LNCaP cells.