Objective： Recombinant human Endostatin （rh-Endostatin, YH-16） can reverse cisplatin resistance in A549/DDP cells. However, the possible effect of rh-Endostatin in reversing DDP-resistance in A549/DDP cells and the...Objective： Recombinant human Endostatin （rh-Endostatin, YH-16） can reverse cisplatin resistance in A549/DDP cells. However, the possible effect of rh-Endostatin in reversing DDP-resistance in A549/DDP cells and the mechanism are needed to be investigated. Methods： Lung adenocarcinoma cell line A549 and its DDP-resistant cell line A549/DDP were treated with DDP and/or recombinant human Endostatin. Difference in drug resistance was analyzed between different regi- mens and between different cell lines after a 72 h-treatment in vitro. And below the non-cytotoxic concentration of rh-End- ostatin, the possibility of rh-Endostatin in reversing DDP-resistance in A549/DDP was evaluated. The resistance protein which was detected in the study included P glycoprotein （P-gp） and topoisomerase II （Topo-II）. Results： Rh-Endostatin below 400 IJg/mL showed no cytotoxicity in either A549 or A549/DDP after 72 h-treatment with it. The inhibited concentration of 50% （IC50） observed for DDP was （0.79 _＋ 0.05） IJg/mL in A549 and （13.2 ＋ 1.1） in A549/DDP respectively. IC50 was reduced to 2.57 ＋ 0.05 #g/mL in A549/DDP treated by rh-Endostatin below the non-cytotoxic concentrations in combination with DDP, with a reversal fold （RF） of 5.14 and a relative reversal rate of 85.6%. Apoptotic rates were 2.01%, 13.47% and 29.26% re- spectively for cells treated with rh-Endostain, DDP, and the combination. The rate of the A549/DDP control group was 0.99%. The expression level of P-gp or Topo-II was higher in A549/DDP cells than in A549 cells. Rh-Endostatin may partially reverse DDP-resistance in A549/DDP cells in vitro, with a probable mechanism related to lowering expression of P-gp and Topo-II. Conclusien： Rh-Endostatin of non-cytotoxic dose partially reversed cisptatin resistance in cisplatin-resistant human lung adenocarcinoma cell line A549/DDP. Rh-Endostatin reversed the resistance of A549/DDP cells to DDP, which may be related to decreased protein expression of P-gp and Topo-II in A549/DDP cells.展开更多
Objective: To investigate the co-expression of drug resistance- and apoptosis-related genes of cisplatin (CDDP)-selected lung adenocarcinoma cell line A 549 DDP for compared to the parental cell line A549, and reverse...Objective: To investigate the co-expression of drug resistance- and apoptosis-related genes of cisplatin (CDDP)-selected lung adenocarcinoma cell line A 549 DDP for compared to the parental cell line A549, and reverse of drug resistance by antisense s-oligodeoxynucleotides (S-ODNs) of differentially expressed genes. Methods: Sense and antisense S-ODN were transferred into A 549 DDP cells by lipofectin. The expression of drug resistance and apoptosis related genes was examined by RT-PCR, immunocytochemistry and flow cytometry, respectively. Apoptostic cells were identified by DNA electrophoresis and terminal deoxynucleotidyl transferase (TdT)-mediated biotin dUTP nick end-labeling(TUNEL). Drug resistance of tumor cells was detected by a cell viability (MTT) assay. Results: The expression of bcl-2 was positive and that of multidrug resistance-associated protein (MRP) at mRNA and protein level was increased in A 549 DDP compared to A549 cells. MDR1, c-myc and topoisomeras II (TOPO II) were similarly co-expressed in two cell lines. Both cell lines were negative for c-erbB-2 expression. In A 549 DDP cells, the expression of bcl-2 and MRP was significantly inhibited by their respective antisense S-ODNs. Antisense S-ODNs could also decrease significantly drug resistance of A 549 DDP cells to CDDP by promoting cell apoptosis. Conclusion: Both intrinsic and acquired drug resistance were involved in co-expression of multiple MDR-related genes in lung adenocarcinoma. Cooperation of bcl-2 and MRP genes appeared to play an important action to confer the resistance of A 549 DDP cells to CDDP. Their antisense S-ODNs are responsible for the decrease of drug resistance of this cell line by promoting apoptosis.展开更多
Obejctive To detect the influence of antisense s oligodeoxynucleotides (S ODNs) of bd 2 and multidrug resistamce associated protein (MRP) genes multidrug resistance associated protein gene and bcl 2 antisen...Obejctive To detect the influence of antisense s oligodeoxynucleotides (S ODNs) of bd 2 and multidrug resistamce associated protein (MRP) genes multidrug resistance associated protein gene and bcl 2 antisense S oligodeoxynucleotides on cisplatin resistant lung adenocarcinoma cell line A 549 DDP which overexpresses both bcl 2 and MRP Methods A 549 DDP cells were treated with sense and antisense S ODN mediated by lipofection Expression of MRP and bcl 2 mRNA and protein in the treated cells was measured by RT PCR and flow cytometry (FCM), respectively Apoptosis was identified by DNA electrophoresis and terminal deoxynucleotidyl transferase (TdT) mediated biotin dUTP nick end labeling(TUNEL) The degree of drug resistance of the treated cells was detected by a cell viability 3' [4,5 dimethylthiazol 2 yl] 2,5 diphenyl tefrazolium bromide thiazolylblue (MTT) assay Results Expression of bcl 2 and MRP significantly decreased in the cells treated with bcl 2 or/and MRP antisense S ODN for 48h as compared to the cells untreated and sense treated ( P <0 05) Resistance to cisplatin in the cells treated with bcl 2 or/and MRP antisense S ODN decreased by 60 6% (6 5 times), 56 4% (7 2 times) and 71 0% (4 8 times), respectively, which paralleled the decrease of bcl 2 and MRP expression Similarly, the resistance to etoposide and epirubicin in antisense treated cells also reduced in parallel to decreases of the two gene expressions The drug resistance in sense treated cells was similar to that in untreated cells Statistically significant dose and concentration dependent increases of apoptotic cells were observed in the groups exposed to 100?μmol/L cisplatin for 48?h after treatment by bcl 2 or/and MRP antisense Conclusion Bcl 2 and MRP were at least additive and possibly synergistic in conferring drug resistance in a cisplatin resistant lung adenocarcinoma cell line Antisense S ODN could attenuate drug resistance by promoting cells apoptosis, which might lead to a new treatment for patients with non small cell lung cancers (NSCLCs) who are refractory to conventional chemotherapy展开更多
基金Supported by a grant from the Natural Science Foundation of Liaoning Province(No.201202043)
文摘Objective： Recombinant human Endostatin （rh-Endostatin, YH-16） can reverse cisplatin resistance in A549/DDP cells. However, the possible effect of rh-Endostatin in reversing DDP-resistance in A549/DDP cells and the mechanism are needed to be investigated. Methods： Lung adenocarcinoma cell line A549 and its DDP-resistant cell line A549/DDP were treated with DDP and/or recombinant human Endostatin. Difference in drug resistance was analyzed between different regi- mens and between different cell lines after a 72 h-treatment in vitro. And below the non-cytotoxic concentration of rh-End- ostatin, the possibility of rh-Endostatin in reversing DDP-resistance in A549/DDP was evaluated. The resistance protein which was detected in the study included P glycoprotein （P-gp） and topoisomerase II （Topo-II）. Results： Rh-Endostatin below 400 IJg/mL showed no cytotoxicity in either A549 or A549/DDP after 72 h-treatment with it. The inhibited concentration of 50% （IC50） observed for DDP was （0.79 _＋ 0.05） IJg/mL in A549 and （13.2 ＋ 1.1） in A549/DDP respectively. IC50 was reduced to 2.57 ＋ 0.05 #g/mL in A549/DDP treated by rh-Endostatin below the non-cytotoxic concentrations in combination with DDP, with a reversal fold （RF） of 5.14 and a relative reversal rate of 85.6%. Apoptotic rates were 2.01%, 13.47% and 29.26% re- spectively for cells treated with rh-Endostain, DDP, and the combination. The rate of the A549/DDP control group was 0.99%. The expression level of P-gp or Topo-II was higher in A549/DDP cells than in A549 cells. Rh-Endostatin may partially reverse DDP-resistance in A549/DDP cells in vitro, with a probable mechanism related to lowering expression of P-gp and Topo-II. Conclusien： Rh-Endostatin of non-cytotoxic dose partially reversed cisptatin resistance in cisplatin-resistant human lung adenocarcinoma cell line A549/DDP. Rh-Endostatin reversed the resistance of A549/DDP cells to DDP, which may be related to decreased protein expression of P-gp and Topo-II in A549/DDP cells.
基金the Grant from Beijing Natural Science Foundation (No.7992005)and a Grantfrom Postdoctoral Foundation of National Committee of E
文摘Objective: To investigate the co-expression of drug resistance- and apoptosis-related genes of cisplatin (CDDP)-selected lung adenocarcinoma cell line A 549 DDP for compared to the parental cell line A549, and reverse of drug resistance by antisense s-oligodeoxynucleotides (S-ODNs) of differentially expressed genes. Methods: Sense and antisense S-ODN were transferred into A 549 DDP cells by lipofectin. The expression of drug resistance and apoptosis related genes was examined by RT-PCR, immunocytochemistry and flow cytometry, respectively. Apoptostic cells were identified by DNA electrophoresis and terminal deoxynucleotidyl transferase (TdT)-mediated biotin dUTP nick end-labeling(TUNEL). Drug resistance of tumor cells was detected by a cell viability (MTT) assay. Results: The expression of bcl-2 was positive and that of multidrug resistance-associated protein (MRP) at mRNA and protein level was increased in A 549 DDP compared to A549 cells. MDR1, c-myc and topoisomeras II (TOPO II) were similarly co-expressed in two cell lines. Both cell lines were negative for c-erbB-2 expression. In A 549 DDP cells, the expression of bcl-2 and MRP was significantly inhibited by their respective antisense S-ODNs. Antisense S-ODNs could also decrease significantly drug resistance of A 549 DDP cells to CDDP by promoting cell apoptosis. Conclusion: Both intrinsic and acquired drug resistance were involved in co-expression of multiple MDR-related genes in lung adenocarcinoma. Cooperation of bcl-2 and MRP genes appeared to play an important action to confer the resistance of A 549 DDP cells to CDDP. Their antisense S-ODNs are responsible for the decrease of drug resistance of this cell line by promoting apoptosis.
文摘Obejctive To detect the influence of antisense s oligodeoxynucleotides (S ODNs) of bd 2 and multidrug resistamce associated protein (MRP) genes multidrug resistance associated protein gene and bcl 2 antisense S oligodeoxynucleotides on cisplatin resistant lung adenocarcinoma cell line A 549 DDP which overexpresses both bcl 2 and MRP Methods A 549 DDP cells were treated with sense and antisense S ODN mediated by lipofection Expression of MRP and bcl 2 mRNA and protein in the treated cells was measured by RT PCR and flow cytometry (FCM), respectively Apoptosis was identified by DNA electrophoresis and terminal deoxynucleotidyl transferase (TdT) mediated biotin dUTP nick end labeling(TUNEL) The degree of drug resistance of the treated cells was detected by a cell viability 3' [4,5 dimethylthiazol 2 yl] 2,5 diphenyl tefrazolium bromide thiazolylblue (MTT) assay Results Expression of bcl 2 and MRP significantly decreased in the cells treated with bcl 2 or/and MRP antisense S ODN for 48h as compared to the cells untreated and sense treated ( P <0 05) Resistance to cisplatin in the cells treated with bcl 2 or/and MRP antisense S ODN decreased by 60 6% (6 5 times), 56 4% (7 2 times) and 71 0% (4 8 times), respectively, which paralleled the decrease of bcl 2 and MRP expression Similarly, the resistance to etoposide and epirubicin in antisense treated cells also reduced in parallel to decreases of the two gene expressions The drug resistance in sense treated cells was similar to that in untreated cells Statistically significant dose and concentration dependent increases of apoptotic cells were observed in the groups exposed to 100?μmol/L cisplatin for 48?h after treatment by bcl 2 or/and MRP antisense Conclusion Bcl 2 and MRP were at least additive and possibly synergistic in conferring drug resistance in a cisplatin resistant lung adenocarcinoma cell line Antisense S ODN could attenuate drug resistance by promoting cells apoptosis, which might lead to a new treatment for patients with non small cell lung cancers (NSCLCs) who are refractory to conventional chemotherapy
