Objective: Overexpression of mdr-1 gene is associated with multidrug resistance (MDR) and aggressive characteristics of malignance. Our purposewas to detect the levels of P-gp expression in fresh untreated esophageal ...Objective: Overexpression of mdr-1 gene is associated with multidrug resistance (MDR) and aggressive characteristics of malignance. Our purposewas to detect the levels of P-gp expression in fresh untreated esophageal carcinomas, and to correlate these levels to current prognostic indicators of morphology.Methods: Reverse transcription polymerase chain reaction (RT-PCR) was used to investigate mdr-1 gene expression of 46 samples from untreated esophageal carcinoma, and compared the positive incidences among differentiated grades, TNM stages and macroscopic types.Results: All 46 samples were pathologically squamous cell carcinoma. The positive' incidences of mdr-1 gene expression were 37% (17/46) in whole group,35% (6/17), 40% (8/20), 33% (3/9), for Ⅰ,Ⅱ and Ⅲdifferentiated grades, respectively. The expression rates of 33% (6/18), 40% (5/12), and 37% (6/16), were found in Ⅱa, Ⅱ, and Ⅲ stage of TNM, respectively. In macroscopic type view, the positive incidence was 37%(3/8) in constrictive, 33% (5/15) in fungating, 40% (6/14)in marrowlike, 33% (319) in ulcerative type. There were no statistically significant differences among each category system of morphology.Conclusion: The result, high level expression of mdr-1 gene in untreated esophageal carcinoma, suggested the poor efficacy of chemotherapy for some esophageal carcinoma patients. And we should cautiously choose cases who will receive chemotherapy. Surgery is still the best treatment for carcinoma of esophagus. Besides, the data also revealed that the expression of mdr-1 gene in untreated esophageal cancer was independent of morphologic prognostic indexes, and that there were no correlation between mdr-1 gene expression and morphological indexes.展开更多
Objective: The purpose of the present study is to detect characteristics of primary expression of mdr 1 gene in several neoplasms which has high morbidity in clinic. Methods: 151 resected samples, which are patholog...Objective: The purpose of the present study is to detect characteristics of primary expression of mdr 1 gene in several neoplasms which has high morbidity in clinic. Methods: 151 resected samples, which are pathologically malignant and clinically untreated before operation, were obtained from Anyang Cancer Hospital. All of them were investigated with RT PCR for the expression of mdr 1 gene and correlated each other. Besides, we evaluated the advantages of RT PCR in this study. Results: The mdr 1 gene expression rate of these 151 samples, including cancers of stomach and gastric cardia (n=51), esophagus (n=46), colorectum (n=16), breast (n=15), thyroid (n=10), lung (n=9), uterine cervix (n=4), was 33.3%, 37%, 31.3%, 13.2%, 40%, 55%, 0%, respectively. Conclusion: Compared with other methods, RT PCR for studying mdr 1 gene expression had certain advantages in simplicity, reliability, and accuracy. Overexpression of mdr 1 gene in these neoplasms suggested that cases should be distinguished before treatment according to MDR of tumor and to choose effective drugs for individual cancer patient.展开更多
Objective: To study the effect of adenovirus- mediated transfer of anti-MDR1 ribozyme on the reversal of multidrug resistant (MDR) phenotype of P-glycoprotein (P-gp)-positive Daudi human Burkitt lymphoma both in vitro...Objective: To study the effect of adenovirus- mediated transfer of anti-MDR1 ribozyme on the reversal of multidrug resistant (MDR) phenotype of P-glycoprotein (P-gp)-positive Daudi human Burkitt lymphoma both in vitro and in vivo. Methods: A recombinant adenovirus expressing 196Rz (Adv-196Rz) was developed and functionally evaluated. SCID mice inoculated subcutaneously (s.c.) with 5?06 Daudi/MDR20 cells were locally treated with Adv-196Rz or mock virus (Adv-Mock) at the multiplicity of infection (MOI) of 400 PFU once a day for 3 consecutive days. Then the mice were intraperitoneally (i.p.) administrated with vincristine (VCR) 450ng/g for 5 consecutive days. Results: In vitro employment of Adv-196Rz was able to interrupt MDR1 transcription, to inhibit P-gp expression and to restore drug sensitivity to VCR of Daudi/MDR20 cells. In vivo, 87.5% (7/8) of Daudi/MDR20-inoculated mice treated with Adv-Mock+ VCR developed palpable tumor by the 6th week and died or were sacrificed (because of tumor weight > 10% of body weight) by the 11th week. In contrast, among 9 Daudi/MDR20-inoculated mice treated with Adv-196Rz + VCR, only 3 developed tumor by the 11th, 13th and 14th week, respectively. 66.7% of mice survived >120 days in tumor-free. The survival difference between the two groups was very significant (P<0.01). Conclusion: Adenovirus- mediated Transfer of 196Rz can revert drug resistance of MDR tumor cells both in vitro and in vivo. Adv-196Rz may prove useful as an adjuvant in the chemotherapy of P-gp mediated MDR human tumors.展开更多
Objective: To investigate retroviral-mediated transfer and expression of human multidrug resistance (MDR) gene MDR1 in leukemic cells. Methods: Human myeloid cells, K562 and NB4, were infected by MDR retrovirus from t...Objective: To investigate retroviral-mediated transfer and expression of human multidrug resistance (MDR) gene MDR1 in leukemic cells. Methods: Human myeloid cells, K562 and NB4, were infected by MDR retrovirus from the producer PA317/HaMDR, and the resistant cells were selected with cytotoxic drug. The transfer and expression of MDR1 gene was analyzed by using polymerase chain reaction (PCR), flow cytometry (FCM) and semisolid colonies cultivation. Results: The resistant cells, K562/MDR and NB4/MDR, in which integration of the exogenous MDR1 gene was confirmed by PCR analysis, displayed a typical MDR phenotype. The expression of MDR1 transgene was detected on truncated as well as full-length transcripts. Moreover, the resistant cells were P-glycoprotein postiive at 78.0% to 98.7% analyzed with FCM. The transduction efficieny in K562 cells was studied on suspension cultures and single-cell colonies. The transduction was more efficient in coculture system (67.9%-72.5%) than in supernatant system (33.1%~46.8%), while growth factors may improve the efficiency. Conclusion: Retrovirus could allow a functional transfer and expression of MDR1 gene in human leukemia cells, and MDR1 might act as a dominant selectable gene for coexpression with the genes of interest in gene therapy.展开更多
A major challenge in the treatment of Tuberculosis (TB) is emergence of Multi-Drug Resistant <em>Mycobacterium tuberculosis</em> (MDRTB) strains. Efflux genes have been established to be among factors for ...A major challenge in the treatment of Tuberculosis (TB) is emergence of Multi-Drug Resistant <em>Mycobacterium tuberculosis</em> (MDRTB) strains. Efflux genes have been established to be among factors for drug resistance in <em>Mycobacterium tuberculosis</em> (<em>M. tuberculosis</em>) pulmonary infections by conferring bacterial ability to pump-out drugs from intracellular compartment, making it impossible for drugs to attain intracellular concentration lethal to the organism. There is paucity of data on the role of efflux pump in MDRTB in Nigerian strains of<em> M. tuberculosis</em>. Hence, the aim of this study was to detect the carriage, distribution and frequency of efflux pump genes among MDRTB and non-MDRTB isolates from participants with pulmonary tuberculosis in Lagos, Nigeria. This study was carried out on <em>M. tuberculosis</em> isolated from 1020 participants suspected of pulmonary tuberculosis in Lagos State, Nigeria. A total of 78 <em>M. tuberculosis</em> isolates were obtained from the participants suspected of pulmonary tuberculosis. Forty Eight isolates were confirmed as MDRTB and 30 non-MDRTB. Efflux pump genes were investigated in the isolates using the conventional polymerase chain reaction. Statistical analysis was carried out using the Statistical Package for Social Science (SPSS version 20) to compare the efflux pump gene results between MDRTB and non- MDRTB isolates. Different efflux genes types and frequency were detected in MDRTB and non-MDRTB isolates. Carriage of 2 or more alleles of efflux gene types Rv2486c (efpA), Rv2459c (jefA), Rv1877, Rv1002c, Rv0342, Rv2686c and drrC associated with MDR were detected. Additionally, the frequency of efflux genes alleles in MDRTB was significantly different from those in non- MDRTB isolates.展开更多
目的:定量检测急性白血病(AL)患者乳腺癌耐药相关蛋白基因(bcrp)、多药耐药基因(mdr-1)、多药耐药相关蛋白基因(mrp-1)及肺耐药相关蛋白基因(lrp)表达及其与临床的关系。方法:应用实时荧光定量逆转录-聚合酶链反应RT-PCR(real time fluo...目的:定量检测急性白血病(AL)患者乳腺癌耐药相关蛋白基因(bcrp)、多药耐药基因(mdr-1)、多药耐药相关蛋白基因(mrp-1)及肺耐药相关蛋白基因(lrp)表达及其与临床的关系。方法:应用实时荧光定量逆转录-聚合酶链反应RT-PCR(real time fluorescent quantitative RT-PCR,FQ RT-PCR)检测105例AL患者bcrp、mdr-1、mrp-1、lrp等基因的拷贝数,分析其与临床预后的关系。结果:AL组bcrp基因拷贝数(2.8×103)±(8.4×103)明显高于正常对照组(7.6×102)±(2.3×103),P<0.05;mdr-1基因拷贝数(1.3×105)±(2.2×105)及lrp基因拷贝数(8.3×105)±(1.0×106)显著高于正常对照组(P<0.01)。复发组AL患者的mdr-1拷贝数(3.7×104)±(1.1×105)明显高于初治组患者(1.1×104)±(3.6×104),P<0.05。在AL耐药组mdr-1拷贝数(2.1×104)±(9.1×104)明显高于敏感组(1.0×104)±(3.8×104),P<0.05)。经直线相关分析显示mdr-1和mrp-1,mdr-1和lrp,mrp-1和lrp之间呈显著正相关,经等级相关分析显示mdr-1和lrp的表达与耐药性密切相关。结论:急性白血病多药耐药的出现与bcrp、mdr-1、mrp-1、lrp中一项或几项过度表达有关,mdr-1较其它基因更具有预测临床预后的意义。展开更多
文摘Objective: Overexpression of mdr-1 gene is associated with multidrug resistance (MDR) and aggressive characteristics of malignance. Our purposewas to detect the levels of P-gp expression in fresh untreated esophageal carcinomas, and to correlate these levels to current prognostic indicators of morphology.Methods: Reverse transcription polymerase chain reaction (RT-PCR) was used to investigate mdr-1 gene expression of 46 samples from untreated esophageal carcinoma, and compared the positive incidences among differentiated grades, TNM stages and macroscopic types.Results: All 46 samples were pathologically squamous cell carcinoma. The positive' incidences of mdr-1 gene expression were 37% (17/46) in whole group,35% (6/17), 40% (8/20), 33% (3/9), for Ⅰ,Ⅱ and Ⅲdifferentiated grades, respectively. The expression rates of 33% (6/18), 40% (5/12), and 37% (6/16), were found in Ⅱa, Ⅱ, and Ⅲ stage of TNM, respectively. In macroscopic type view, the positive incidence was 37%(3/8) in constrictive, 33% (5/15) in fungating, 40% (6/14)in marrowlike, 33% (319) in ulcerative type. There were no statistically significant differences among each category system of morphology.Conclusion: The result, high level expression of mdr-1 gene in untreated esophageal carcinoma, suggested the poor efficacy of chemotherapy for some esophageal carcinoma patients. And we should cautiously choose cases who will receive chemotherapy. Surgery is still the best treatment for carcinoma of esophagus. Besides, the data also revealed that the expression of mdr-1 gene in untreated esophageal cancer was independent of morphologic prognostic indexes, and that there were no correlation between mdr-1 gene expression and morphological indexes.
文摘Objective: The purpose of the present study is to detect characteristics of primary expression of mdr 1 gene in several neoplasms which has high morbidity in clinic. Methods: 151 resected samples, which are pathologically malignant and clinically untreated before operation, were obtained from Anyang Cancer Hospital. All of them were investigated with RT PCR for the expression of mdr 1 gene and correlated each other. Besides, we evaluated the advantages of RT PCR in this study. Results: The mdr 1 gene expression rate of these 151 samples, including cancers of stomach and gastric cardia (n=51), esophagus (n=46), colorectum (n=16), breast (n=15), thyroid (n=10), lung (n=9), uterine cervix (n=4), was 33.3%, 37%, 31.3%, 13.2%, 40%, 55%, 0%, respectively. Conclusion: Compared with other methods, RT PCR for studying mdr 1 gene expression had certain advantages in simplicity, reliability, and accuracy. Overexpression of mdr 1 gene in these neoplasms suggested that cases should be distinguished before treatment according to MDR of tumor and to choose effective drugs for individual cancer patient.
基金This work was supported in part by theNational Natural Science Foundation of China (No. 39970831).
文摘Objective: To study the effect of adenovirus- mediated transfer of anti-MDR1 ribozyme on the reversal of multidrug resistant (MDR) phenotype of P-glycoprotein (P-gp)-positive Daudi human Burkitt lymphoma both in vitro and in vivo. Methods: A recombinant adenovirus expressing 196Rz (Adv-196Rz) was developed and functionally evaluated. SCID mice inoculated subcutaneously (s.c.) with 5?06 Daudi/MDR20 cells were locally treated with Adv-196Rz or mock virus (Adv-Mock) at the multiplicity of infection (MOI) of 400 PFU once a day for 3 consecutive days. Then the mice were intraperitoneally (i.p.) administrated with vincristine (VCR) 450ng/g for 5 consecutive days. Results: In vitro employment of Adv-196Rz was able to interrupt MDR1 transcription, to inhibit P-gp expression and to restore drug sensitivity to VCR of Daudi/MDR20 cells. In vivo, 87.5% (7/8) of Daudi/MDR20-inoculated mice treated with Adv-Mock+ VCR developed palpable tumor by the 6th week and died or were sacrificed (because of tumor weight > 10% of body weight) by the 11th week. In contrast, among 9 Daudi/MDR20-inoculated mice treated with Adv-196Rz + VCR, only 3 developed tumor by the 11th, 13th and 14th week, respectively. 66.7% of mice survived >120 days in tumor-free. The survival difference between the two groups was very significant (P<0.01). Conclusion: Adenovirus- mediated Transfer of 196Rz can revert drug resistance of MDR tumor cells both in vitro and in vivo. Adv-196Rz may prove useful as an adjuvant in the chemotherapy of P-gp mediated MDR human tumors.
基金a grant from the Public Health Bureau of Jiangsu Province (H9549).
文摘Objective: To investigate retroviral-mediated transfer and expression of human multidrug resistance (MDR) gene MDR1 in leukemic cells. Methods: Human myeloid cells, K562 and NB4, were infected by MDR retrovirus from the producer PA317/HaMDR, and the resistant cells were selected with cytotoxic drug. The transfer and expression of MDR1 gene was analyzed by using polymerase chain reaction (PCR), flow cytometry (FCM) and semisolid colonies cultivation. Results: The resistant cells, K562/MDR and NB4/MDR, in which integration of the exogenous MDR1 gene was confirmed by PCR analysis, displayed a typical MDR phenotype. The expression of MDR1 transgene was detected on truncated as well as full-length transcripts. Moreover, the resistant cells were P-glycoprotein postiive at 78.0% to 98.7% analyzed with FCM. The transduction efficieny in K562 cells was studied on suspension cultures and single-cell colonies. The transduction was more efficient in coculture system (67.9%-72.5%) than in supernatant system (33.1%~46.8%), while growth factors may improve the efficiency. Conclusion: Retrovirus could allow a functional transfer and expression of MDR1 gene in human leukemia cells, and MDR1 might act as a dominant selectable gene for coexpression with the genes of interest in gene therapy.
文摘A major challenge in the treatment of Tuberculosis (TB) is emergence of Multi-Drug Resistant <em>Mycobacterium tuberculosis</em> (MDRTB) strains. Efflux genes have been established to be among factors for drug resistance in <em>Mycobacterium tuberculosis</em> (<em>M. tuberculosis</em>) pulmonary infections by conferring bacterial ability to pump-out drugs from intracellular compartment, making it impossible for drugs to attain intracellular concentration lethal to the organism. There is paucity of data on the role of efflux pump in MDRTB in Nigerian strains of<em> M. tuberculosis</em>. Hence, the aim of this study was to detect the carriage, distribution and frequency of efflux pump genes among MDRTB and non-MDRTB isolates from participants with pulmonary tuberculosis in Lagos, Nigeria. This study was carried out on <em>M. tuberculosis</em> isolated from 1020 participants suspected of pulmonary tuberculosis in Lagos State, Nigeria. A total of 78 <em>M. tuberculosis</em> isolates were obtained from the participants suspected of pulmonary tuberculosis. Forty Eight isolates were confirmed as MDRTB and 30 non-MDRTB. Efflux pump genes were investigated in the isolates using the conventional polymerase chain reaction. Statistical analysis was carried out using the Statistical Package for Social Science (SPSS version 20) to compare the efflux pump gene results between MDRTB and non- MDRTB isolates. Different efflux genes types and frequency were detected in MDRTB and non-MDRTB isolates. Carriage of 2 or more alleles of efflux gene types Rv2486c (efpA), Rv2459c (jefA), Rv1877, Rv1002c, Rv0342, Rv2686c and drrC associated with MDR were detected. Additionally, the frequency of efflux genes alleles in MDRTB was significantly different from those in non- MDRTB isolates.
