Fig. 2

CBD could effectively induce ER stress in OC cells. (A) DEGs identified in ES-2 cells before and after being treated with 40 µM CBD. Volcano plot for the DEGs. Red, blue and gray points represent up-regulated, down-regulated, and non-regulated DEGs, respectively. (B) GO enrichment analysis of the upregulated DEGs before and after being treated with 40 µM CBD. The most significant GO terms were those with corrected p-value of < 0.05. The rich factor represents the number of DEGs that exist in this term accounting for the total number of genes of this term. (C) ES-2 cells were pre-incubated with 4-PBA, AM251 or NAC for 30 min at indicated concentrations. Cells were subsequently co-incubated with CBD at indicated concentrations. After 24 h, the cell inhibition rate was detected by CCK-8 assay. (D) ES-2 cells were pre-incubated with 4-PBA for 30 min at a final concentration of 500 µM and then further co-incubated with CBD at indicated concentrations. After 24 h, total cellular RNA was extracted and reverse transcribed. The mRNA transcription levels of ER stress-related genes GRP78, XBP1, ATF6, PERK, ATF4, and CHOP were detected by RT-qPCR as described in methods. Heatmap represents log2 values of relative mRNA transcription levels (see color scale). The log2 value of each gene in control cells was set to 0. Untreated cells served as a negative control. (E–I) The protein expression levels of the ER stress-related factors were detected by western blot analysis. Each value indicates the mean ± SD of results obtained from three independent experiments. *p < 0.05, **p < 0.01, *** p < 0.001.