Curcumin Reverses 5-Fluorouracil Resistance by Promoting Human Colon Cancer HCT-8/5-FU Cell Apoptosis and Down-regulating Heat Shock Protein 27 and P-Glycoprotein.

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/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. 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 cells 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 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). 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.

Cohort Study on Prognosis of Patients with Metastatic Colorectal Cancer Treated with Integrated Chinese and Western Medicine.

OBJECTIVE: To investigate the efficacy of integrated Chinese and Western medicine (IM) in the treatment of metastatic colorectal cancer (mCRC) in a cohort study. METHODS: The survival outcome of patients receiving IM was compared with that of patients receiving Western medicine alone. The study design was adopted with "continuous administration of Chinese medicine for ⩾ 3 months" as the exposure factor. Patients who met this exposure factor were assigned to the IM cohort (Group A, 110 patients). Patients who did not meet this exposure factor were assigned to the Western medicine cohort (Group B, 225 patients). The overall survival (OS), progression-free survival (PFS), and 1st year, 2nd year, and 3rd year survival in the two cohorts were compared. RESULTS: The median OS in Group A and B were 18 months [95% confidence interval (CI) 15-21] and 16 months (95% CI 14-18), respectively, and the median PFS in Group A and B were 6 months (95% CI 4-7) and 5 months (95% CI 4-6), respectively. No statistically significant differences were observed between the groups (P=0.186, P=0.223). Group A demonstrated significantly longer OS and PFS than Group B in the following subgroups: female patients, patients with lesions in the right half of the colon, and those who received first-line treatment (P<0.05). In the subgroup of elderly patients (age>65 years), the OS in Group A was longer than that in Group B (P<0.05). CONCLUSION: IM could prolong the survival of patients with mCRC. (Registry No. ChiCTR-IOR-17010497).

[Characteristic genomics of peripheral blood mononuclear cells of hepatocellular carcinoma patients with liver-kidney yin deficiency syndrome].

OBJECTIVE: To explore the characteristic genomics of syndrome of liver-kidney yin deficiency in peripheral blood mononuclear cells of hepatocellular carcinoma (HCC) patients. METHODS: HCC patients with or without syndrome of liver-kidney yin deficiency were enrolled into the experimental group and the control group, respectively; their gene expression profiles were evaluated by a whole-genome Affymetrix GeneChip Human Genome U133 Plus 2.0 Array. The differentially expressed mRNAs were then selected by Gene Ontology (GO) and pathway analyses, respectively. Based on the results of GO and pathway analyses, gene coexpression networks were built according to the normalized signal intensity of specifically expressed genes. Finally, the results from microarray were confirmed by real-time fluorescence quantitative polymerase chain reaction and Western blot methods. RESULTS: The results showed that a set of 615 mRNAs were differentially expressed in the HCC patients with syndrome of liver-kidney yin deficiency. By GO enrichment analysis, the genes for anti-apoptosis, regulation of cell cycle, transmembrane transport, etc. were up-regulated or down-regulated in the experimental group. Another functional analysis of mRNAs by KEGG revealed that 10 signal transduction pathways were up-regulated and 16 were down-regulated, such as antigen processing and presentation, cell cycle, and protein export. Based on the above results, we constructed coexpression networks to determine which genes may play pivotal role in HCC patients with syndrome of liver-kidney yin deficiency. Some critical genes, including SEC62 (SEC62 homolog (S. cerevisiae)), CCNB1 (cyclin B1) and BIRC3 (baculoviral IAP repeat-containing 3), which rank the top 3 in |δ normalized degree| were chosen. Of another 60 samples, we found that the mRNA expressions of SEC62, CCNB1 and BIRC3 were significantly lower in HCC patients with syndrome of liver-kidney yin deficiency than those without syndrome of liver-kidney yin deficiency (P<0.01). Also, the protein expressions of SEC62, CCNB1 and BIRC3 were significantly lower (P<0.01). CONCLUSION: Gene chip technique allows rapid and high-throughput screening for different gene expression in HCC patients with or without liver-kidney yin deficiency syndrome. The results of this study further confirm the hypothesis on the essence of syndrome, namely, a kind of deviation from the normal state in multigene style on the levels of both mRNA and protein.