Objective: To study the reversal effect of neferine on adriamycin (ADM) resistant human breast cancer cell line MCF-7/ADM. Methods: The cytotoxic effect of Nef or ADM was determined by 3-[4, 5-dimethylthiazol-2.-yl], ...Objective: To study the reversal effect of neferine on adriamycin (ADM) resistant human breast cancer cell line MCF-7/ADM. Methods: The cytotoxic effect of Nef or ADM was determined by 3-[4, 5-dimethylthiazol-2.-yl], 5-diphenyl tetraxolium bromid (MTT) assay. Apoptosis and the expression of P-glycoprotein (P-gp) were detected by flow cytometry (FCM). The intracellular ADM concentration was measured by HPLC. Results: Nef at 1, 5, 10 mol/L decreased the IC50 of ADM to MCF-7/ADM from 11.63 g/mL to 4.59, 2.44, 0.27 g/mL respectively. MCF-7/ADM could resist the apoptosis induced by ADM while Nef (1-10 mol/L) could augment ADR-mediated apoptosis. Nef (10 mol/L) increased the accumulation of ADM up to 2.88 fold in MCF-7/ADM but not in sensitive cells MCF-7/S and reduced the expression of P-gp in MCF-7/ADM cells. Conclusion: Nef can circumvent multidrug resistance (MDR) of MCF-7/ADM cells and the mechanism was associated with the increase of intracellular accumulation of ADM and the reduced expression of P-gp in MCF-7/ADM cells.展开更多
OBJECTIVE To study the expression levels of Twist and epithelialmesenchymal transitions in multidrug-resistant MCF-7/ADR breast cancer cells, and to study the relationship between multidrug resistance （MDR） and meta...OBJECTIVE To study the expression levels of Twist and epithelialmesenchymal transitions in multidrug-resistant MCF-7/ADR breast cancer cells, and to study the relationship between multidrug resistance （MDR） and metastatic potential of the cells. METHODS RT-PCR, immunohistochemical and Western blotting methods were used to examine the changes of expression levels of the transcription factor Twist, E-cadherin and N-cadherin in the MCF-7 breast cancer cell line and its multidrug-resistant variant, MCF-7/ADR. RESULTS In MCF-7 cells, the expression of E-cadherin can be detected, but there is no expression of Twist or N-cadherin. In MCF-7/ADR cells, E-cadherin expression is lost, but the expression of two other genes was significantly positive. CONCLUSION Epithelial-mesenchymal transitions induced by Twist, may have a relationship with enhanced invasion and metastatic potential during the development of multidrug-resistant MCF-7/ADR breast cancer cells.展开更多
Objective： The aim of this study was to investigate the relationship between p38MAPK activity and apoptosis during the drug resistance of breast carcinoma cell lines. Methods： Using p38MAPK special inhibitor SB20358...Objective： The aim of this study was to investigate the relationship between p38MAPK activity and apoptosis during the drug resistance of breast carcinoma cell lines. Methods： Using p38MAPK special inhibitor SB203580 to analyze the effect on the cell apoptosis of MCF-7/ADM cell. Cell apoptosis was analysed by PI staining and flow cytometry （FCM） （F test）. 50% inhibition concentration （IC50） of adriamycin on MCF-7/ADM was determined by MTT method （F test） in vitro. MDR-1 mRNA expression was detected by RT-PCR （F test） and Western Blot （F test） respectively. Results： After SB203580 24 h action the MCF-7/ADM＇s apoptosis rate was 26.73±4.90%, higher than the control group and untreated group （F = 143.80, P 〈 0.001）. The sensitity to the ADM was improved significantly （F = 148927.1, P 〈 0.001）, and the reversal effect of treat SB203580 group was 68.45%. The P38MAPK protein （F= 685.419, P 〈 0.001） and MDR-1 mRNAexpression after SB203580 24 h action were lower than the control group and untreated group （F = 9139.24, P 〈 0.001）. Conclusion： P38MAPK signal way plays an important role in drug resistance of breast carcinoma ceil. p38MAPK can protect MCF-7/ADM cells from apoptosis, and blocking the p38MAPK signal way can increase the apoptosis for breast carcinoma drug resistance cell lines.展开更多
文摘Objective: To study the reversal effect of neferine on adriamycin (ADM) resistant human breast cancer cell line MCF-7/ADM. Methods: The cytotoxic effect of Nef or ADM was determined by 3-[4, 5-dimethylthiazol-2.-yl], 5-diphenyl tetraxolium bromid (MTT) assay. Apoptosis and the expression of P-glycoprotein (P-gp) were detected by flow cytometry (FCM). The intracellular ADM concentration was measured by HPLC. Results: Nef at 1, 5, 10 mol/L decreased the IC50 of ADM to MCF-7/ADM from 11.63 g/mL to 4.59, 2.44, 0.27 g/mL respectively. MCF-7/ADM could resist the apoptosis induced by ADM while Nef (1-10 mol/L) could augment ADR-mediated apoptosis. Nef (10 mol/L) increased the accumulation of ADM up to 2.88 fold in MCF-7/ADM but not in sensitive cells MCF-7/S and reduced the expression of P-gp in MCF-7/ADM cells. Conclusion: Nef can circumvent multidrug resistance (MDR) of MCF-7/ADM cells and the mechanism was associated with the increase of intracellular accumulation of ADM and the reduced expression of P-gp in MCF-7/ADM cells.
基金the grants from National Natural Science Foundation (No.30370553) of China Tianjin Medi-cal University Natural Science Foundation (No.2005KY41).
文摘OBJECTIVE To study the expression levels of Twist and epithelialmesenchymal transitions in multidrug-resistant MCF-7/ADR breast cancer cells, and to study the relationship between multidrug resistance （MDR） and metastatic potential of the cells. METHODS RT-PCR, immunohistochemical and Western blotting methods were used to examine the changes of expression levels of the transcription factor Twist, E-cadherin and N-cadherin in the MCF-7 breast cancer cell line and its multidrug-resistant variant, MCF-7/ADR. RESULTS In MCF-7 cells, the expression of E-cadherin can be detected, but there is no expression of Twist or N-cadherin. In MCF-7/ADR cells, E-cadherin expression is lost, but the expression of two other genes was significantly positive. CONCLUSION Epithelial-mesenchymal transitions induced by Twist, may have a relationship with enhanced invasion and metastatic potential during the development of multidrug-resistant MCF-7/ADR breast cancer cells.
文摘Objective： The aim of this study was to investigate the relationship between p38MAPK activity and apoptosis during the drug resistance of breast carcinoma cell lines. Methods： Using p38MAPK special inhibitor SB203580 to analyze the effect on the cell apoptosis of MCF-7/ADM cell. Cell apoptosis was analysed by PI staining and flow cytometry （FCM） （F test）. 50% inhibition concentration （IC50） of adriamycin on MCF-7/ADM was determined by MTT method （F test） in vitro. MDR-1 mRNA expression was detected by RT-PCR （F test） and Western Blot （F test） respectively. Results： After SB203580 24 h action the MCF-7/ADM＇s apoptosis rate was 26.73±4.90%, higher than the control group and untreated group （F = 143.80, P 〈 0.001）. The sensitity to the ADM was improved significantly （F = 148927.1, P 〈 0.001）, and the reversal effect of treat SB203580 group was 68.45%. The P38MAPK protein （F= 685.419, P 〈 0.001） and MDR-1 mRNAexpression after SB203580 24 h action were lower than the control group and untreated group （F = 9139.24, P 〈 0.001）. Conclusion： P38MAPK signal way plays an important role in drug resistance of breast carcinoma ceil. p38MAPK can protect MCF-7/ADM cells from apoptosis, and blocking the p38MAPK signal way can increase the apoptosis for breast carcinoma drug resistance cell lines.
