Second Department of Oncology, Traditional Chinese Medicine Hospital of Xinjiang Uyghur Autonomous Region, Uyghur, 830000, China.
Department of Oncology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, 100091, China.
Chin J Integr Med. 2019 Jun;25(6):416-424. doi: 10.1007/s11655-018-2997-z. Epub 2018 Nov 27.
To investigate the potential mechanisms that curcumin reverses 5-fluorouracil (5-FU) multidrug resistance (MDR).
Cell growth and the inhibitory rate of curcumin (2-25 μg/mL) and/or 5-FU (0.05-1000 μg/mL) on human colon cancer HCT-8 and HCT-8/5-FU (5-FU-resistant cell line) were determined using cell counting kit-8 (CCK-8) assay. Apoptosis and cell cycle after 5-FU and/or curcumin treatment were detected by flow 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.
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 (IC) 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 IC 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 cells mostly accumulated at G/G phase, which suggested a synergistic effect of curcumin and 5-FU to induce apoptosis. FCM analysis found that the percentage of apoptosis of cells treated with curcumin, 5-FU and their combination were significantly 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 mRNA levels of P-gp (0.28±0.02) and HSP-27 (0.28±0.09) in HCT-8/5-FU cells treated with combination drugs were lower than cells 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).
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.
研究姜黄素逆转 5-氟尿嘧啶（5-FU）多药耐药（MDR）的潜在机制。
使用细胞计数试剂盒-8（CCK-8）测定姜黄素（2-25 μg/mL）和/或 5-FU（0.05-1000 μg/mL）对人结肠癌细胞 HCT-8 和 HCT-8/5-FU（5-FU 耐药细胞系）的细胞生长和抑制率。通过流式细胞术（FCM）和透射电子显微镜（TEM）检测 5-FU 和/或姜黄素处理后的细胞凋亡和细胞周期。通过逆转录聚合酶链反应（RT-PCR）和 Western blot（WB）分别分析多药耐药相关因子 P-糖蛋白（P-gp）和热休克蛋白 27（HSP-27）基因和蛋白的表达。
姜黄素或 5-FU 对 HCT-8 和 HCT-8/5-FU 细胞增殖的抑制率呈剂量依赖性，与 HCT-8/5-FU 相比，HCT-8 细胞系对姜黄素或 5-FU 更为敏感。HCT-8/5-FU 中联合 5-FU 和姜黄素（4.0 μg/mL）的 50%抑制浓度（IC）计算为 179.26 μg/mL，逆转倍数为 1.85。HCT-8/5-FU 中联合 5-FU 和姜黄素（5.5 μg/mL）的另一个 IC 计算为 89.25 μg/mL，逆转倍数为 3.71。在 HCT-8 和 HCT-8/5-FU 细胞中发现了 5-FU 和姜黄素的协同作用。FCM 细胞周期分析表明，HCT-8 和 HCT-8/5-FU 细胞主要积聚在 G/G 期，这表明姜黄素和 5-FU 协同诱导细胞凋亡。FCM 分析发现，与对照组相比，用姜黄素、5-FU 及其组合处理的细胞凋亡率显著增加（P<0.05），且组合组的细胞凋亡率略高于其他组（P<0.05）。联合用药组 HCT-8/5-FU 细胞 P-gp（0.28±0.02）和 HSP-27（0.28±0.09）mRNA 水平低于单独用 5-FU 处理的细胞（P-gp，0.48±0.07，P=0.009；HSP-27，0.57±0.10，P=0.007）。与单独用 5-FU 处理的细胞相比，联合用药组 HCT-8/5-FU 细胞 P-gp（0.25±0.06）和 HSP-27（0.09±0.02）蛋白水平降低（P-gp，0.46±0.02，P=0.005；HSP-27，0.43±0.01，P=0.000）。
姜黄素能抑制人结肠癌细胞的增殖。姜黄素对人结肠癌细胞系 HCT-8/5-FU 的多药耐药具有逆转作用。下调 P-gp 和 HSP-27 可能是姜黄素逆转 HCT-8/5-FU 对 5-FU 耐药的机制。
