Hexahydrocurcumin enhances inhibitory effect of 5-fluorouracil on HT-29 human colon cancer cells

Figure 4 Combination effects of hexahydrocurcumin and 5-fluorouracil on cyclooxygenase-2 mRNA expression in HT-29 colon cancer cells. The HT-29 cells were exposed to 5-fluorouracil (5-FU) (5 μmol/L), hexahydrocurcumin (HHC) (25 μmol/L) and their combination for 24 h. Cells from different experimental groups were subjected to semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). A: RT-PCR showed that the expression of cyclooxygenase (COX)-2 (305 bp) was significantly decreased in HHC or combination of HHC and 5-FU-treated group; B: The expression of COX-2 was determined by normalizing the band intensity of COX-2 with glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Values are expressed as percentage of control (mean ± SE), ^aP < 0.05 vs control; ^cP < 0.05 vs 5-FU or HHC monotherapy (n = 3).