Fig. 7. metAEA enhances CXCR4-mediated pro-invasive capacity of human BC cell lines through a CBR-mediated mechanism.

a Representative WB analysis of CXCR4 in T-47D parental cells after being treated with metAEA (1 nM) alone or in combination with SR1 or SR2 (1 μM) for 24 h. Antagonists were added to the cells 1 h before metAEA. Densitometric analysis is shown in purple. n = 3 biological replicates. Invasion of T-47D (b) and MDA-MB-231 (c) under the treatment of metAEA (1 nM) alone or in combination with SR1, SR2, or AMD3100 (1 μM) as determined in matrigel-coated Boyden chambers. Antagonists were added to the upper compartment 1 h before metAEA. Data are presented as mean values ± SEM of n = 5 biological replicates and were analyzed by 1-way ANOVA with post-Tukey’s multiple comparison test. d Lung metastatic damage caused by parental and FAAH-overexpressing MDA-MB-231 cells in immunocompromised mice treated with metAEA (0.1 mg/kg) alone or in combination with SR1, SR2 or AMD3100 (2.5 mg/kg). Metastatic damage was monitored with an IVIS system and categorized into four scores depending on bioluminescence values. Pearson’s chi-squared test was used for statistical analysis. e Kaplan-Meier curves for overall survival of BC patients with high and low AEA levels. Kaplan-Meier curves were statistically compared by the log-rank test. f Schematic drawing of the proposed metastasis-suppressor mechanism of FAAH in BC cells. On the left, high FAAH expression determines low anandamide (AEA) tone and a luminal-like phenotype. On the right, low FAAH expression allows higher AEA levels that, acting through cannabinoid receptors (CBR), induce the expression of CXCR4 and CXCR4-mediated pro-metastatic responses. Yellow asterisks represent activated receptors. Source data are provided as a Source Data file.