Objective: To investigate the potential mechanisms that curcumin reverses 5-fluorouracil(5-FU) multidrug resistance(MDR). Methods: Cell growth and the inhibitory rate of curcumin(2–25 μg/mL) and/or5-FU(0.05–1000 μ...Objective: To investigate the potential mechanisms that curcumin reverses 5-fluorouracil(5-FU) multidrug resistance(MDR). Methods: Cell growth and the inhibitory rate of curcumin(2–25 μg/mL) and/or5-FU(0.05–1000 μg/mL) on human colon cancer HCT-8 and HCT-8/5-FU(5-FU-resistant cel line) were determined using cel counting kit-8(CCK-8) assay. Apoptosis and cel cycle after 5-FU and/or curcumin treatment were detected by ?ow cytometry(FCM) and transmission electron microscopy(TEM). The expression of the multidrug resistance related factors p-glycoprotein(P-gp) and heat shock protein 27(HSP-27) genes and proteins were analyzed by reverse transcription polymerase chain reaction(RT-PCR) and Western blotting(WB), respectively. Results: The inhibitory rate of curcumin or 5-FU on HCT-8 and HCT-8/5-FU cells proliferation at exponential phase were in a dosedependent manner, HCT-8 cell line was more sensitive to curcumin or 5-FU when compared the inhibitory rate of HCT-8/5-FU. The 50% inhibitory concentration(IC50) of combination 5-FU and curcumin(4.0 μg/mL)in HCT-8/5-FU was calculated as 179.26 μg/mL, with reversal fold of 1.85. Another IC50 of combination 5-FU and curcumin(5.5 μg/mL) in HCT-8/5-FU was calculated as 89.25 μg/mL, with reversal fold of 3.71. Synergistic effect of 5-FU and curcumin on HCT-8 and HCT-8/5-FU cells were found. The cell cycle analysis performed by FCM showed that HCT-8 and HCT-8/5-FU cel s mostly accumulated at G0/G1 phase, which suggested a synergistic effect of curcumin and 5-FU to induce apoptosis. FCM analysis found that the percentage of apoptosis of cel s treated with curcumin, 5-FU and their combination were signi?cantly increased compared to the control group(P<0.05), and the percentage of apoptosis of the combination groups were slightly higher than other groups(P<0.05). The m RNA levels of P-gp(0.28±0.02) and HSP-27(0.28±0.09) in HCT-8/5-FU cel s treated with combination drugs were lower than cel s treated with 5-FU alone(P-gp, 0.48±0.07, P=0.009;HSP-27, 0.57±0.10, P=0.007). The protein levels of P-gp(0.25±0.06) and HSP-27(0.09±0.02) in HCT-8/5-FU cells treated with combination drugs were decreased when compared to 5-FU alone(P-gp, 0.46±0.02, P=0.005;HSP-27, 0.43±0.01, P=0.000). Conclusions: Curcumin can inhibit the proliferation of human colon cancer cells. Curcumin has the ability of reversal effects on the multidrug resistance of human colon cancer cells lines HCT-8/5-FU. Down-regulation of P-gp and HSP-27 may be the mechanism of curcumin reversing the drug resistance of HCT-8/5-FU to 5-FU.展开更多
AIM: To investigate the combined chemotherapeutic effects of celecoxib when used with 5-FU in vitro. METHODS: Two human colon cancer cell lines (HCT-15 and HT-29) were treated with 5-FU and celecoxib, alone and in com...AIM: To investigate the combined chemotherapeutic effects of celecoxib when used with 5-FU in vitro. METHODS: Two human colon cancer cell lines (HCT-15 and HT-29) were treated with 5-FU and celecoxib, alone and in combination. The effects of each drug were evaluated using the MTT [3- (4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide] assay, flow cytometry, and western blotting. RESULTS: 5-FU and celecoxib showed a dose- dependent cytotoxic effect. When treated with 10-3 mol/L 5-FU (IC50) and celecoxib with its concentration ranging from 10-8 mol/L to 10-4 mol/L of celecoxib, cells showed reduced cytotoxic effect than 5-FU (10-3 mol/L) alone. Flow cytometry showed that celecoxib attenuated 5-FU induced accumulation of cells at subG1 phase. Western blot analyses for caspase-3 and poly (ADP-ribose) polymerase (PARP) cleavage showed that celecoxib attenuated 5-FU induced apoptosis. Western blot analyses for cell cycle molecules showed that G2/M arrest might be possible cause of 5-FU induced apoptosis and celecoxib attenuated 5-FU induced apoptosis via blocking of cell cycle progression to the G2/M phase, causing an accumulation of cells at the G1/S phase. CONCLUSION: We found that celecoxib attenuated cytotoxic effect of 5-FU. Celecoxib might act via inhibition of cell cycle progression, thus preventing apoptosis induced by 5-FU.展开更多
基金Supported by China Science Fund of Clinical Oncology(No.Y-L2014-002)
文摘Objective: To investigate the potential mechanisms that curcumin reverses 5-fluorouracil(5-FU) multidrug resistance(MDR). Methods: Cell growth and the inhibitory rate of curcumin(2–25 μg/mL) and/or5-FU(0.05–1000 μg/mL) on human colon cancer HCT-8 and HCT-8/5-FU(5-FU-resistant cel line) were determined using cel counting kit-8(CCK-8) assay. Apoptosis and cel cycle after 5-FU and/or curcumin treatment were detected by ?ow cytometry(FCM) and transmission electron microscopy(TEM). The expression of the multidrug resistance related factors p-glycoprotein(P-gp) and heat shock protein 27(HSP-27) genes and proteins were analyzed by reverse transcription polymerase chain reaction(RT-PCR) and Western blotting(WB), respectively. Results: The inhibitory rate of curcumin or 5-FU on HCT-8 and HCT-8/5-FU cells proliferation at exponential phase were in a dosedependent manner, HCT-8 cell line was more sensitive to curcumin or 5-FU when compared the inhibitory rate of HCT-8/5-FU. The 50% inhibitory concentration(IC50) of combination 5-FU and curcumin(4.0 μg/mL)in HCT-8/5-FU was calculated as 179.26 μg/mL, with reversal fold of 1.85. Another IC50 of combination 5-FU and curcumin(5.5 μg/mL) in HCT-8/5-FU was calculated as 89.25 μg/mL, with reversal fold of 3.71. Synergistic effect of 5-FU and curcumin on HCT-8 and HCT-8/5-FU cells were found. The cell cycle analysis performed by FCM showed that HCT-8 and HCT-8/5-FU cel s mostly accumulated at G0/G1 phase, which suggested a synergistic effect of curcumin and 5-FU to induce apoptosis. FCM analysis found that the percentage of apoptosis of cel s treated with curcumin, 5-FU and their combination were signi?cantly increased compared to the control group(P<0.05), and the percentage of apoptosis of the combination groups were slightly higher than other groups(P<0.05). The m RNA levels of P-gp(0.28±0.02) and HSP-27(0.28±0.09) in HCT-8/5-FU cel s treated with combination drugs were lower than cel s treated with 5-FU alone(P-gp, 0.48±0.07, P=0.009;HSP-27, 0.57±0.10, P=0.007). The protein levels of P-gp(0.25±0.06) and HSP-27(0.09±0.02) in HCT-8/5-FU cells treated with combination drugs were decreased when compared to 5-FU alone(P-gp, 0.46±0.02, P=0.005;HSP-27, 0.43±0.01, P=0.000). Conclusions: Curcumin can inhibit the proliferation of human colon cancer cells. Curcumin has the ability of reversal effects on the multidrug resistance of human colon cancer cells lines HCT-8/5-FU. Down-regulation of P-gp and HSP-27 may be the mechanism of curcumin reversing the drug resistance of HCT-8/5-FU to 5-FU.
文摘AIM: To investigate the combined chemotherapeutic effects of celecoxib when used with 5-FU in vitro. METHODS: Two human colon cancer cell lines (HCT-15 and HT-29) were treated with 5-FU and celecoxib, alone and in combination. The effects of each drug were evaluated using the MTT [3- (4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide] assay, flow cytometry, and western blotting. RESULTS: 5-FU and celecoxib showed a dose- dependent cytotoxic effect. When treated with 10-3 mol/L 5-FU (IC50) and celecoxib with its concentration ranging from 10-8 mol/L to 10-4 mol/L of celecoxib, cells showed reduced cytotoxic effect than 5-FU (10-3 mol/L) alone. Flow cytometry showed that celecoxib attenuated 5-FU induced accumulation of cells at subG1 phase. Western blot analyses for caspase-3 and poly (ADP-ribose) polymerase (PARP) cleavage showed that celecoxib attenuated 5-FU induced apoptosis. Western blot analyses for cell cycle molecules showed that G2/M arrest might be possible cause of 5-FU induced apoptosis and celecoxib attenuated 5-FU induced apoptosis via blocking of cell cycle progression to the G2/M phase, causing an accumulation of cells at the G1/S phase. CONCLUSION: We found that celecoxib attenuated cytotoxic effect of 5-FU. Celecoxib might act via inhibition of cell cycle progression, thus preventing apoptosis induced by 5-FU.
