Article Figures & Data
Figures
- Figure 1.
Cytotoxicity of indole-3-carbinol (I3C) (A and C) and gemcitabine (B) towards Panc-1 cells. Panc-1 cells were forward to be gemcitabine-resistant because the half-maximal inhibitory concentration (IC50) of gemcitabine was 9 mM (B). However, treatment of 100 μM I3C was minimally cytotoxic towards Panc-1 cells (A and C). Values were obtained from at least three separate experiments. I3C, Indole-3-carbinol.
- Figure 2.
microRNA-21 (miR-21) expression after indole-3-carbinol (I3C) treatment of Panc-1 cells according to time of exposure to (A) and concentration of (B) I3C. I3C concentration was 100 μM in (A) and the time of exposure was 24 h in (B). miR-21 expression was reduced by I3C in a time- and dose-dependent manner. *p<0.05; **p<0.01.
- Figure 3.
Real-time cell analyzer assay according to gemcitabine and/or indole-3-carbinol (I3C) treatment. The assay demonstrated the enhancement of cytotoxicity after treating cells with I3C and gemcitabine (blue line), compared to gemcitabine alone (green line) (A). In microscopic findings, gemcitabine with pre-treatment of I3C led to fewer viable cells than with gemcitabine or I3C alone (B). Gem, Gemcitabine.
- Figure 4.
Gemcitabine resistance of Panc-1 increased after miR-21 transfection. A: CCK-8 assay. B: Microscopic findings. When miR-21 was transfected into Panc-1, indole-3-carbinol (I3C)-induced gemcitabine cytotoxicity was significantly weakened. Gem, Gemcitabine; NC, negative control. **p<0.01; ***p<0.001.
- Figure 5.
Cell-cycle analysis. There was no significant difference in cell arrest after administration of gemcitabine and/or indole-3-carbinol (I3C). Moreover, there was little change in sub-G1 phase after I3C administration, thus I3C-alone had minimal cytotoxicity towards Panc-1 cells. NT, No treatment; Gem, gemcitabine.
- Figure 6.
Western blots demonstrating the increase of programmed cell death-4 (PDCD4) expression in Panc-1 cells after 48 h treatment with indole-3-carbinol (I3C) alone and after 24 h treatment of gemcitabine after I3C (A). On the contrary, PDCD4 expression decreased after transfection of miR-21 (B). β-Actin was used as a loading control. NT, No treatment; Gem, gemcitabine; NC, negative control.
- Figure 7.
DNA fragmentation assay (A) and TUNEL assay (B) showing apoptosis enhancement by gemcitabine (gem) and indole-3-carbinol (I3C) combination treatment. I3C down-regulates miR-21 and eventually increases the expression of programmed cell death-4 (PDCD4), which induces apoptosis. Inhibition of apoptosis after miR-21 transfection is clear. The green color in the TUNEL assay indicates apoptotic cells. NT, No treatment.
