Effects of Jianpi Jiedu Recipe on reversion of P-glycoprotein-mediated multidrug resistance through COX-2 pathway in colorectal cancer / 中国结合医学杂志

<p><b>OBJECTIVE</b>To evaluate the underlying mechanism of Jianpi Jiedu Recipe (, JJR) in the reversion of multidrug resistance concerning colorectal cancer in vitro and in vivo.</p><p><b>METHODS</b>Mice were treated orally with JJR at a daily 4.25 g/(kg·day) or injected with vinblastine (VCR) 2.5 mg/(kg·day) for 3 weeks after having been inoculated with HCT8/V cells; tumor tissues were assayed by hematoxylin and eosin staining. Firstly, the effects of JJR on the expression of cyclooxygenase-2 (COX-2) were tested by real-time polymerase chain reaction (PCR) technique and COX-2 gene silenced by siRNA. Secondly, the variation of intracellular concentration of oxaliplatin (L-OHP) was evaluated by the inductively coupled plasma mass spectroscopy (ICPMS) in HCT8/V and its COX-2 siRNA cells; the concentration of JJR combined with chemotherapeutic drugs and the reverse effect of multidrug resistance (MDR) in HCT8/V cells was evaluated by the MTT assay. Thirdly, real-time quantitative PCR and Western blot analysis were used to detect the multidrug resistance gene 1 (MDR1) mRNA and P-gp expression.</p><p><b>RESULTS</b>JJR had an inhibitory effect on the growth of tumors in vivo, and it, in combination with chemotherapeutic drugs, could reverse the drug-resistance of HCT8/V cells and increase the sensitivity of HCT8/V cells to VCR, DDP, 5-Fu, and THP. ICP-MS results showed that JJR could increase the concentration of drugs in HCT8/V cells (P<0.01). Furthermore, it was shown that JJR could reverse drug resistance of colorectal cancer cells by decreasing MDR1 expression and P-gp level via downregulation of COX-2, which has been represented as one of the major mechanisms that contributes to the MDR phenotype (P<0.01).</p><p><b>CONCLUSION</b>JJR reversed multidrug resistance and enhanced the sensitivity to chemotherapy, which could be attributed to the down-regulation of COX-2 in MDR1/P-gp-mediated MDR colorectal cancer after chemotherapy.</p>

In vitro antimetastatic effect of Changweiqing through antiinvasion of hypoxic colorectal carcinoma LoVo cells / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the in vitro effects and the primary mechanisms of Changweiqing (, CWQ) on antimetastasis and antiinvasion of hypoxic colon carcinoma cells. In addition, to provide experimental evidence for the Chinese medicinal theory of "strengthening the body's resistance to eliminate pathogenic factors" in the treatment of colorectal cancer, including its invasion and metastasis.</p><p><b>METHODS</b>First, CWQ sera were prepared with serum-pharmacology methods. Then, the modified hypoxic chamber was designed and flushed with 5% CO(2) and 95% N(2) at 37 °C to induce a hypoxic environment. The effect of CWQ serum on the viability of LoVo cells was tested with MTT cytotoxicity assay. The wound model and chamber model were established to estimate the effects of CWQ serum on migration and invasion of LoVo cells. The model for cell adhesion was established to evaluate the effect of CWQ serum on LoVo cells' adhesion. The gelatin zymography model was performed to determine the effects of CWQ serum on the activities of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9). The effects of CWQ serum on the hypoxia-inducible factor 1 α (HIF-1α) nuclear translocation and the mRNA level of vascular endothelial growth factor (VEGF) in LoVo cells were determined by Western blot and reverse transcription-polymerase chain reaction (RT-PCR) analyses, respectively.</p><p><b>RESULTS</b>CWQ inhibited LoVo cells' migration based on wound healing assay. The inhibitive effect could reach about 68.00% under hypoxic culture and about 29.87% under normoxic culture when cells were treated with 10% CWQ serum for 24 h. The results from both cell invasion and adhesion assays showed that CWQ serum could dose-dependently repress the invasion of LoVo cells and inhibit cells from adhering to extra cellular matrix (ECM). Under the hypoxic culture condition, RT-PCR analysis showed that 10% CWQ serum had down-regulated the expression of VEGF by 45.87%, and the result of Western blot analysis provided further evidence. The HIF-1α amount in the nucleus of the LoVo cells was also diminished in a dose-dependent manner, as shown by the Western blot. Gel zymogram assay revealed that CWQ serum could suppress the activities of MMP-2 and MMP-9.</p><p><b>CONCLUSIONS</b>CWQ could effectively inhibit tumor metastasis in vitro The antimetastatic effects of CWQ were associated with the inhibition of cell motility, which was evidenced by inhibition of cell invasion and adhesion. The molecular mechanisms of the inhibition of tumor invasion by CWQ were due to the reduced expression of both HIF-1α and VEGF and the suppression of MMP-2 and MMP-9 expression.</p>

Effects of changwelqing on nuclear translocation of Y-box binding protein-1 and expression of P-glycoprotein in human colon cancer cell line with drug-resistance induced by vincristine / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To evaluate the effects and molecular mechanism of action of Changweiqing (CWQ) in reversing multidrug resistance by observing its impacts on nuclear translocation of Y-box binding protein-1 (YB-1), multi-drug resistance gene (MDR1) expression and P-glycoprotein (P-gp) expression in human colon cancer cell line HCT8/V with drug-resistance induced by vincristine.</p><p><b>METHODS</b>Cultured HCT8/V cells were exposed to the CWQ-containing rat serum prepared by drug perfusion. YB-1 expressions in cell plasma and nuclei were examined by Western blot; the binding activity of YB-1 to MDR1 gene promoter sequences was detected by electrophoretic mobility shift assay (EMSA); the mRNA transcription levels of MDR1, YB-1 and multi-resistance related protein (MRP) were examined by RT-PCR; the expression of P-gp on cell membrane was determined by flow cytometry. Results Along with the increasing drug's concentration of CWQ-containing serum from 1.25% up to 2.5% and 5%, the expressions of YB-1 decreased in HCT8/V cell nuclear and increased in cytoplasm gradually; the binding activity of YB-1 to MDR1 gene promoter weakened (P < 0.01), MDR1 mRNA expression and fluorescence intensity of P-gp on cell membrane attenuated (P < 0.05 or P < 0.01), while YB-1 and MRP mRNA unchanged (P > 0.05).</p><p><b>CONCLUSION</b>CWQ could reverse the drug-resistance of colon cancer cells by influencing nuclear translocation of YB-1 and reducing the expression of MDR1/P-gp.</p>

Study of Helicobacterpylori on p38MAPK signal transduction pathway activation in gastric epithelial cancer cells line MKN45 / 中国癌症杂志

Background and purpose:Cyclooxygenase-2 (Cyclooxygenase-2,COX-2) is an important rate-limiting enzyme that is responsible for transformation of arachidonic acid into prostaglandins(PGs).Although Helicobacter pylori(Hp) infection-induced gastric over-expression of COX-2 (COX-2) is an important factor of gastric cancer,the mechanism of COX-2 expression in gastric mucosa cells infected with Hp is still not clear.Our study was to reveal the effect of Hp on expression of COX-2(cyclooxygenase-2),the impact of p38MAPK signaling pathway in human gastric epithelial cancer cells line MKN45,and to investigate the potential mechanisms of expression of COX-2. Methods:The expression of COX-2 mRNA infection by standard Hp NCTC11637 in human gastric epithelial cancer cells line MKN45 was evaluated by real-time fluorogenic quantitative polymerase chain reaction (RFQ-PCR).The effect of infection by Hp on COX-2 expression,activation of p38MAPK and its downstream of the ATF-2 was assayed by Western blot.Results:The expression of COX-2 mRNA in MKN45 cells infected by Hp compared with control group,COX-2 mRNA had 3 fold,7.2 fold,5.1 fold,4.3 fold up-regulation after 3 hrs,6 hrs,9 hrs,12 hrs,respectively. COX-2 mRNA expression in each time group was significantly higher than that in the control group(P