Figure 1.
Effects of mCAR ligands alone or in combination with Paclitaxel in E9 mouse lung cancer cells.
(A) Cell viability after 48 hours of different concentrations of the mCAR agonist TCPOBOP or the mCAR inverse-agonist androstenol. TCPOBOP has no effect on cell viability even at the highest concentration. On the other hand, androstenol increases the number of E9 cancer cells dose-dependently (* p<0.05 – Two way ANOVA followed by Tukey's multiple comparison test for treatment effect). (B) Effects of mCAR ligands on the anti-tumor efficacy of paclitaxel (IC50). TCPOBOP increases the anti-tumor efficacy of the of paclitaxel by significant decrease cell viability at 1–10 µM compared to only paclitaxel-treated cells (p<0.05 – Two way ANOVA followed by Tukey's multiple comparison test for treatment effect). The androstenol partially abolishes the anti-tumor efficacy of paclitaxel (p<0.05 – Two way ANOVA followed by Tukey's multiple comparison test for treatment effect). (C) Gene expression of mCAR in cells treated with ligands alone, paclitaxel alone, or in combination. Ligands did not alter mCAR gene expression. Note that all paclitaxel treated-groups presented increased mCAR gene expression compared to control group (* p<0.05 – One way ANOVA).
Table 1.
IC50 of Paclitaxel in mouse and human lung cancer cell lines.
Figure 2.
Effects of hCAR ligands on the anti-tumor efficacy of paclitaxel in six different human lung cancer cells.
Cell viability after 48-agonist Androstenol in combination with Paclitaxel. CITCO enhances paclitaxel cytotoxicity significantly in five of six cell lines (* p<0.05 – Two way ANOVA followed by Tukey's multiple comparison test for treatment effect). On the other hand, androstenol in combination with paclitaxel has no effect in comparison to paclitaxel-treated cells.
Table 2.
Altered gene expression by Paclitaxel, TCPOBOP and their combination in E9 cells.
Figure 3.
Docking using CAR crystal structure with ligand (PDB-1XLS) TCPOBOP (A, B, and C) and with ligand (PDB-1XNX) androstenol (D-H).
A, D-Androstenol; B, E-Paclitaxel; C,F-TCPOBOP; G and H *androstenol and TCPOBOP superposition: G- surface view and H- wire view of ligands. Note that paclitaxel docked in both mCAR structures.
Table 3.
Energy grid of mCAR ligands and paclitaxel docking against XLS and XNX structures.
Figure 4.
hCAR characterization in two NSCLC independent studies.
(A) Genetic alterations and frequency of hCAR in the Lung Adenocarcinoma study available from TCGA. (B) Same data from the Lung Squamous Cell Carcinoma study available from TCGA. (C) DNA methylation vs gene expression of hCAR from Lung Adenocarcinoma samples from TCGA. (D) DNA methylation vs gene expression of hCAR from Lung Squamous Cell Carcinoma samples from TCGA. Both datasets presented highly DNA methylation and variable levels of mRNA expression of NR1I3.