Objective: To evaluate the expression and clinical significance of multidrug resistance gene (mdr1) and multidrug resistance-associated protein (MRP) gene in acute leukemia. Methods: The expression of mdr1 and MRP ass...Objective: To evaluate the expression and clinical significance of multidrug resistance gene (mdr1) and multidrug resistance-associated protein (MRP) gene in acute leukemia. Methods: The expression of mdr1 and MRP assay in 55 patients with acute leukemia (AL) by reverse transcription polymerase chain reaction (RT-PCR). Results: The mdr1 and MRP gene expression levels in the relapsed AL and the blastic plastic phases of CML were significantly higher than those in the newly diagnostic AL and controls. The mdr1 and MRP gene expression levels in the clinical drug-resistant group were significantly higher than those in the non-drug-resistant group. The complete remission (CR) rate in patients with high mdr1 expression (14.3%) was significantly lower than that with low mdr1 expression (57.5%); similarly the CR rate in patients with high MRP level was also lower than that with low MRP level. Using both high expression of mdr1 and MRP gene as the indicator for evaluating multidrug resistance (MDR), the positive predictive value and accuracy increased in comparison with single gene high expression. Conclusion: Elevated level of mdr1 or MRP gene expression might be unfavorable prognostic factors for AL patient and may be used as an important index for predicting drug-resistance and relapse in AL patient. Measuring both mdr1 and MRP gene expression would increase accuracy and sensibility of evaluating MDR in acute leukemia.展开更多
Objective: To investigate the relationship between the expression of multidrug resistance-associated protein (MRP) and clinicopathological factors and prognosis. Methods: The expression of MRP in 62 cases with non-sma...Objective: To investigate the relationship between the expression of multidrug resistance-associated protein (MRP) and clinicopathological factors and prognosis. Methods: The expression of MRP in 62 cases with non-small cell lung cancer (NSCLC) was detected using immunohistochemistry method. The expression of MRP in 30 cases of NSCLC and corresponding normal lung tissues were detected using immunohistochemistry and Western Blot. Results: this study of tumor tissues confirmed the plasma membrane and/or cytoplasm locations of MRP. There was apparent difference between normal lung tissues and NSCLC in MRP. The survival analysis of 62 NSCLC showed that the mean survival time of the patients with negative MRP expression was 69.8117.41 months and that of patients with positive MRP expression, 25.384.46 months. Log-rank test suggested that the difference between them was significant (P=0.0156). It was also found that in squamous cell lung cancer the statistically significant difference between the mean survival time of patients with positive MRP expression and those with negative MRP expression (P=0.0153). Multivariate Cox model analysis suggested that the survival time was significantly related to expression of MRP (P=0.035) and lymphatic metastasis (P=0.038). Conclusion: MRP expression in NSCLC is significantly higher compared with normal lung tissues. The mean survival time of patients with negative MRP was relative longer and expression of MRP was an independent factor for prognosis.展开更多
BACKGROUND:Multidrug resistance(MDR)is extremely common in hepatocellular carcinoma(HCC)and is a major problem in cancer eradication by limiting the efficacy of chemotherapy.Modulation of c-Jun NH2-terminal kinase(JNK...BACKGROUND:Multidrug resistance(MDR)is extremely common in hepatocellular carcinoma(HCC)and is a major problem in cancer eradication by limiting the efficacy of chemotherapy.Modulation of c-Jun NH2-terminal kinase(JNK)activation could be a new method to reverse MDR.However,the relationship between JNK activity and MDR in HCC cells is unknown.This study aimed to explore the relationship between MDR and JNK in HCC cell lines with different degrees of MDR.METHODS:A MDR human HCC cell line,SMMC-7721/ ADM,was developed by exposing parental cells to gradually increasing concentrations of adriamycin.The MTT assay was used to determine drug sensitivity.Flow cytometry was used to analyze the cell cycle distribution and to measure the expression levels of P-glycoprotein(P-gp)and MDR-related protein(MRP)-1 in these cells.JNK1,JNK2 and JNK3 mRNA expression levels were quantified by real-time PCR.Expression and phosphorylation of JNK1,JNK2,and JNK3 were analyzed by Western blotting.RESULTS:The MDR of SMMC-7721/ADM cells resistant to 0.05 mg/L adriamycin was mainly attributed to the overexpression of P-gp but not MRP1.In addition,these cells had a significant increase in percentage in the S phase,accompanied by a decrease in percentage in the G0/G1 phase,which is likely associated with a reduced ability for cell proliferation and MDR generation.We found that JNK1,JNK2,and JNK3 activities were negatively correlated with the degree of MDR in HCC cells.CONCLUSION:This study suggests that JNK1,JNK2,and JNK3 activities are negatively correlated with the degree of MDR in HCC cells.展开更多
AIM： To study the expression and phosphorylation of extracellular signal-regulated kinase （ERK） i and ERK2 in multidrug resistant （MDR） hepatocellular carcinoma （HCC） cells.METHODS： MDR HCC cell lines, HepG2/a...AIM： To study the expression and phosphorylation of extracellular signal-regulated kinase （ERK） i and ERK2 in multidrug resistant （MDR） hepatocellular carcinoma （HCC） cells.METHODS： MDR HCC cell lines, HepG2/adriamycin （ADM） and SMMC7721/ADM, were developed by exposing parental cells to stepwise increasing concentrations of ADM. MTT assay was used to determine drug sensitivity. Flow cytometry was employed to analyze cell cycle distribution and measure cell P-glycoprotein （P-gp） and multidrug resistant protein 1 （MRP1） expression levels. ERK1 and ERK2 mRNA expression lev-ls were measured by quantitative real-time PCR （QRTPCR）. Expression and phosphorylation of ERK1 and ERK2 were analyzed by Western blot.RESULTS： MTT assay showed that HepG2/ADM andSMMC7721/ADM were resistant not only to ADM, but also to multiple anticancer drugs. The P-gp expression was over 10-fold higher in HepG2/ADM cells than in HepG2 cells （8.92% ±0.22% vs 0.88% ± 0.05%, P 〈 0.001） and over 4-fold higher in SMMC7721/ADM cells than in SMMC7721 cells （7.37% ± 0.26% vs 1.74% ± 0.25%, P 〈 0.001）. However, the MRP1 expression was not significantly higher in HepG2/ADM and SMMC7721/ADM cells than in parental cells. In addition, the percentage of MDR HepG2/ADM and SMMC7721/ADM cells was significantly decreased in the G0/G1 phase and increased in the the S phase or G2/M phase. QRT-PCR analysis demonstrated that the ERK1 and ERK2 mRNA expression increased apparently in HepG2/ADM cells and decreased significantly in SMMC7721/ADM cells. Compared with the expression of parental cells, ERK1 and ERK2 protein expressions were markedly decreased in SMMC7721/ADM cells. However, ERK2 protein expression was markedly increased while ERK1 protein expression had no significant change in HepG2/ADM cells. Phosphorylation of ERK1 and ERK2 was markedly decreased in both HepG2/ADM and SMMC7721/ADM MDR cells.CONCLUSION： ERK1 and ERK2 activities are downregulated in P-gp-mediated MDR HCC cells. ERK1 or ERK2 might be a potential drug target for circumventing MDR HCC cells,展开更多
AIM：To investigate the altering expression profiles of efflux transporters such as breast cancer-resistance protein（BCRP）,lung resistance protein（LRP）,and multidrug resistance protein 1（MDR1） at the inner blood...AIM：To investigate the altering expression profiles of efflux transporters such as breast cancer-resistance protein（BCRP）,lung resistance protein（LRP）,and multidrug resistance protein 1（MDR1） at the inner blood-retinal barrier（BRB） during the development of early diabetic retinopathy（DR） and/or aging in mice.METHODS：Relative m RNA and protein expression profiles of these three efflux transporters in the retina during the development of early DR and/or aging in mice were examined.The differing expression profiles of Zonula occludens 1（ ZO-1） and vascular endothelial growth factor-A（ VEGFA） in the retina as well as the perfusion characterization of fluorescein isothiocyanate（FITC）-dextran and Evans blue were examined to evaluate the integrity of the inner BRB.RESULTS：There were significant alterations in these three efflux transporters＇ expression profiles in the m RNA and protein levels of the retina during the development of diabetes mellitus and/or aging.The development of early DR was confirmed by the expression profiles of ZO-1 and VEGFA in the retina as well as the compromised integrity of the inner BRB.CONCLUSION：The expression profiles of some efflux transporters such as BCRP,LRP,and MDR1 in mice retina during diabetic and/or aging conditions are tested,and the attenuated expression of BCRP,LRP,and MDR1 along with the breakdown of the inner BRB is found,which may be linked to the pathogenesis of early DR.展开更多
BACKGROUND:Sulfonylurea receptor 1(SUR1)and multidrug resistance protein 1(MRP1)are two prominent members of multidrug resistance proteins associated with insulin secretion. The aims of this study were to investigate ...BACKGROUND:Sulfonylurea receptor 1(SUR1)and multidrug resistance protein 1(MRP1)are two prominent members of multidrug resistance proteins associated with insulin secretion. The aims of this study were to investigate their expression in insulinomas and their sole and synergistic effects in modulating abnormal insulin secretion. METHODS:Fasting glucose,insulin and C-peptide were measured in 11 insulinoma patients and 11 healthy controls. Prolonged oral glucose tolerance tests were performed in 6 insulinoma patients.Insulin content,SUR1 and MRP1 were detected in 11 insulinoma patients by immunohistochemistry. SUR1 and MRP1 were also detected in 6 insulinoma patients by immunofluorescence. RESULTS:Insulinoma patients presented the typical demons-trations of Whipple’s triad.Fasting glucose of each insulinoma patient was lower than 2.8 mmol/L,and simultaneous insulin and C-peptide were increased in insulinoma patients. Prolonged oral glucose tolerance tests showed that insulin secretion in insulinoma patients were also stimulated by high glucose.Immunohistochemistry and immunofluorescence staining showed that SUR1 increased,but MRP1 decreased in insulinoma compared with the adjacent islets. CONCLUSIONS:The hypersecretion of insulin in insulinomas might be,at least partially,due to the enrichment of SUR1. In contrast,MRP1,which is down-regulated in insulinomas, might reflect a negative feedback in insulin secretion.展开更多
Objective To investigate the expression and meaning of MRP3 in different tumor cells. MethodsThe monoclonal antibody against MRP3 was used to identify the expression of MRP3 by flow cytometer in seven tumor cells and ...Objective To investigate the expression and meaning of MRP3 in different tumor cells. MethodsThe monoclonal antibody against MRP3 was used to identify the expression of MRP3 by flow cytometer in seven tumor cells and human embryo kidney cell lines 293T.And RT-PCR was used to detect the mRNA of MRP3 in eight cell lines. ResultsThe mRNA of MRP3 was expressed in three pancreatic carcinoma cell lines.MRP3 protein was observed in BxPC-3 and AsPC-1 cells. ConclusionMRP3 may express in different tumor in tissue-specific manner.BxPC-3 and AsPC-1 may serve as cellular models for in vitro studies on multidrug resistance of pancreatic carcinoma.展开更多
文摘Objective: To evaluate the expression and clinical significance of multidrug resistance gene (mdr1) and multidrug resistance-associated protein (MRP) gene in acute leukemia. Methods: The expression of mdr1 and MRP assay in 55 patients with acute leukemia (AL) by reverse transcription polymerase chain reaction (RT-PCR). Results: The mdr1 and MRP gene expression levels in the relapsed AL and the blastic plastic phases of CML were significantly higher than those in the newly diagnostic AL and controls. The mdr1 and MRP gene expression levels in the clinical drug-resistant group were significantly higher than those in the non-drug-resistant group. The complete remission (CR) rate in patients with high mdr1 expression (14.3%) was significantly lower than that with low mdr1 expression (57.5%); similarly the CR rate in patients with high MRP level was also lower than that with low MRP level. Using both high expression of mdr1 and MRP gene as the indicator for evaluating multidrug resistance (MDR), the positive predictive value and accuracy increased in comparison with single gene high expression. Conclusion: Elevated level of mdr1 or MRP gene expression might be unfavorable prognostic factors for AL patient and may be used as an important index for predicting drug-resistance and relapse in AL patient. Measuring both mdr1 and MRP gene expression would increase accuracy and sensibility of evaluating MDR in acute leukemia.
文摘Objective: To investigate the relationship between the expression of multidrug resistance-associated protein (MRP) and clinicopathological factors and prognosis. Methods: The expression of MRP in 62 cases with non-small cell lung cancer (NSCLC) was detected using immunohistochemistry method. The expression of MRP in 30 cases of NSCLC and corresponding normal lung tissues were detected using immunohistochemistry and Western Blot. Results: this study of tumor tissues confirmed the plasma membrane and/or cytoplasm locations of MRP. There was apparent difference between normal lung tissues and NSCLC in MRP. The survival analysis of 62 NSCLC showed that the mean survival time of the patients with negative MRP expression was 69.8117.41 months and that of patients with positive MRP expression, 25.384.46 months. Log-rank test suggested that the difference between them was significant (P=0.0156). It was also found that in squamous cell lung cancer the statistically significant difference between the mean survival time of patients with positive MRP expression and those with negative MRP expression (P=0.0153). Multivariate Cox model analysis suggested that the survival time was significantly related to expression of MRP (P=0.035) and lymphatic metastasis (P=0.038). Conclusion: MRP expression in NSCLC is significantly higher compared with normal lung tissues. The mean survival time of patients with negative MRP was relative longer and expression of MRP was an independent factor for prognosis.
基金supported by grants from the Medical Innovation Fundation of Fujian Province(No.2007-CXB-7)the Natural Science Foundation of Fujian Province(No.2009D010)
文摘BACKGROUND:Multidrug resistance(MDR)is extremely common in hepatocellular carcinoma(HCC)and is a major problem in cancer eradication by limiting the efficacy of chemotherapy.Modulation of c-Jun NH2-terminal kinase(JNK)activation could be a new method to reverse MDR.However,the relationship between JNK activity and MDR in HCC cells is unknown.This study aimed to explore the relationship between MDR and JNK in HCC cell lines with different degrees of MDR.METHODS:A MDR human HCC cell line,SMMC-7721/ ADM,was developed by exposing parental cells to gradually increasing concentrations of adriamycin.The MTT assay was used to determine drug sensitivity.Flow cytometry was used to analyze the cell cycle distribution and to measure the expression levels of P-glycoprotein(P-gp)and MDR-related protein(MRP)-1 in these cells.JNK1,JNK2 and JNK3 mRNA expression levels were quantified by real-time PCR.Expression and phosphorylation of JNK1,JNK2,and JNK3 were analyzed by Western blotting.RESULTS:The MDR of SMMC-7721/ADM cells resistant to 0.05 mg/L adriamycin was mainly attributed to the overexpression of P-gp but not MRP1.In addition,these cells had a significant increase in percentage in the S phase,accompanied by a decrease in percentage in the G0/G1 phase,which is likely associated with a reduced ability for cell proliferation and MDR generation.We found that JNK1,JNK2,and JNK3 activities were negatively correlated with the degree of MDR in HCC cells.CONCLUSION:This study suggests that JNK1,JNK2,and JNK3 activities are negatively correlated with the degree of MDR in HCC cells.
基金Supported by Innovation Fund of Fujian Province,No.2007-CXB-7Key Science and Technology Project of Xiamen,No.3502Z20077045
文摘AIM： To study the expression and phosphorylation of extracellular signal-regulated kinase （ERK） i and ERK2 in multidrug resistant （MDR） hepatocellular carcinoma （HCC） cells.METHODS： MDR HCC cell lines, HepG2/adriamycin （ADM） and SMMC7721/ADM, were developed by exposing parental cells to stepwise increasing concentrations of ADM. MTT assay was used to determine drug sensitivity. Flow cytometry was employed to analyze cell cycle distribution and measure cell P-glycoprotein （P-gp） and multidrug resistant protein 1 （MRP1） expression levels. ERK1 and ERK2 mRNA expression lev-ls were measured by quantitative real-time PCR （QRTPCR）. Expression and phosphorylation of ERK1 and ERK2 were analyzed by Western blot.RESULTS： MTT assay showed that HepG2/ADM andSMMC7721/ADM were resistant not only to ADM, but also to multiple anticancer drugs. The P-gp expression was over 10-fold higher in HepG2/ADM cells than in HepG2 cells （8.92% ±0.22% vs 0.88% ± 0.05%, P 〈 0.001） and over 4-fold higher in SMMC7721/ADM cells than in SMMC7721 cells （7.37% ± 0.26% vs 1.74% ± 0.25%, P 〈 0.001）. However, the MRP1 expression was not significantly higher in HepG2/ADM and SMMC7721/ADM cells than in parental cells. In addition, the percentage of MDR HepG2/ADM and SMMC7721/ADM cells was significantly decreased in the G0/G1 phase and increased in the the S phase or G2/M phase. QRT-PCR analysis demonstrated that the ERK1 and ERK2 mRNA expression increased apparently in HepG2/ADM cells and decreased significantly in SMMC7721/ADM cells. Compared with the expression of parental cells, ERK1 and ERK2 protein expressions were markedly decreased in SMMC7721/ADM cells. However, ERK2 protein expression was markedly increased while ERK1 protein expression had no significant change in HepG2/ADM cells. Phosphorylation of ERK1 and ERK2 was markedly decreased in both HepG2/ADM and SMMC7721/ADM MDR cells.CONCLUSION： ERK1 and ERK2 activities are downregulated in P-gp-mediated MDR HCC cells. ERK1 or ERK2 might be a potential drug target for circumventing MDR HCC cells,
基金Supported by the National Natural Science Foundation of China(No.81271036No.81500751)+1 种基金the Key Research Project of Shandong Province,China(No.2015GSF118121)the Natural Science Foundation of Shandong Province,China(No.ZR2015PH062)
文摘AIM：To investigate the altering expression profiles of efflux transporters such as breast cancer-resistance protein（BCRP）,lung resistance protein（LRP）,and multidrug resistance protein 1（MDR1） at the inner blood-retinal barrier（BRB） during the development of early diabetic retinopathy（DR） and/or aging in mice.METHODS：Relative m RNA and protein expression profiles of these three efflux transporters in the retina during the development of early DR and/or aging in mice were examined.The differing expression profiles of Zonula occludens 1（ ZO-1） and vascular endothelial growth factor-A（ VEGFA） in the retina as well as the perfusion characterization of fluorescein isothiocyanate（FITC）-dextran and Evans blue were examined to evaluate the integrity of the inner BRB.RESULTS：There were significant alterations in these three efflux transporters＇ expression profiles in the m RNA and protein levels of the retina during the development of diabetes mellitus and/or aging.The development of early DR was confirmed by the expression profiles of ZO-1 and VEGFA in the retina as well as the compromised integrity of the inner BRB.CONCLUSION：The expression profiles of some efflux transporters such as BCRP,LRP,and MDR1 in mice retina during diabetic and/or aging conditions are tested,and the attenuated expression of BCRP,LRP,and MDR1 along with the breakdown of the inner BRB is found,which may be linked to the pathogenesis of early DR.
文摘BACKGROUND:Sulfonylurea receptor 1(SUR1)and multidrug resistance protein 1(MRP1)are two prominent members of multidrug resistance proteins associated with insulin secretion. The aims of this study were to investigate their expression in insulinomas and their sole and synergistic effects in modulating abnormal insulin secretion. METHODS:Fasting glucose,insulin and C-peptide were measured in 11 insulinoma patients and 11 healthy controls. Prolonged oral glucose tolerance tests were performed in 6 insulinoma patients.Insulin content,SUR1 and MRP1 were detected in 11 insulinoma patients by immunohistochemistry. SUR1 and MRP1 were also detected in 6 insulinoma patients by immunofluorescence. RESULTS:Insulinoma patients presented the typical demons-trations of Whipple’s triad.Fasting glucose of each insulinoma patient was lower than 2.8 mmol/L,and simultaneous insulin and C-peptide were increased in insulinoma patients. Prolonged oral glucose tolerance tests showed that insulin secretion in insulinoma patients were also stimulated by high glucose.Immunohistochemistry and immunofluorescence staining showed that SUR1 increased,but MRP1 decreased in insulinoma compared with the adjacent islets. CONCLUSIONS:The hypersecretion of insulin in insulinomas might be,at least partially,due to the enrichment of SUR1. In contrast,MRP1,which is down-regulated in insulinomas, might reflect a negative feedback in insulin secretion.
文摘Objective To investigate the expression and meaning of MRP3 in different tumor cells. MethodsThe monoclonal antibody against MRP3 was used to identify the expression of MRP3 by flow cytometer in seven tumor cells and human embryo kidney cell lines 293T.And RT-PCR was used to detect the mRNA of MRP3 in eight cell lines. ResultsThe mRNA of MRP3 was expressed in three pancreatic carcinoma cell lines.MRP3 protein was observed in BxPC-3 and AsPC-1 cells. ConclusionMRP3 may express in different tumor in tissue-specific manner.BxPC-3 and AsPC-1 may serve as cellular models for in vitro studies on multidrug resistance of pancreatic carcinoma.
