Figure 8. Verticillin A exhibits greater efficacy than decitabine or vorinostat in sensitizing 5-FU-resistant metastatic CRC cells to FasL-induced apoptosis.

A. SW620-5FU-R and LS411N-5FU-R cells were cultured in the presence of decitabine, vorinostat, verticillin A, and FasL, either alone or in the indicated combinations and doses, for 24h. Cells were then stained with PI and Annexin V and analyzed by flow cytometry. Shown are represent images of apoptotic cell death. B. The data shown in A were quantified as 1) % apoptosis = % Annexin V⁺ treated cells - % Annexin V⁺ untreated control cells; and 2) % apoptotic cell death= % PI⁺Annexin V⁺ treated cells - % PI⁺Annexin V⁺ untreated control cells. Column: mean, bar: SD. ** p<0.01. C. SW620-5FU-R cells were transfected with scramble or Fas-specific siRNA (200 nM) overnight and analyzed for Fas mRNA level by RT-PCR. D. The cells as shown in C were then treated with verticillin A (20 nM) and FasL for 24h and analyzed by staining with Annexin V and PI. % apoptotic cell death is calculated as % Annexin V⁺PI⁺ cells. * p<0.05.