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
Objective: To clone multidrug resistance (MDR) related genes in lung adenocarcinoma cell lines. Methods: The differentially expressed cDNA fragments between A549 and A549 DDP cells were analyzed by mRNA differential d...Objective: To clone multidrug resistance (MDR) related genes in lung adenocarcinoma cell lines. Methods: The differentially expressed cDNA fragments between A549 and A549 DDP cells were analyzed by mRNA differential display PCR(DD RT-PCR). The fragments thus obtained were further analyzed by DNA sequencing and Northern blotting. Results: Three differentially expressed cDNA fragments were obtained and confirmed by Northern blot. Sequence analysis revealed that two of them were novel and one was 100% identical with ICE gene. Conclusion: Analyzing differentially expressed fragment between A549 and A549 DDP cells may be helpful for finding new MDR related genes. The drug resistance of A549 DDP cells may be related to the inhibition or down-regulation of ICE gene.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Objective: To clone multidrug resistance (MDR) related genes in lung adenocarcinoma cell lines. Methods: The differentially expressed cDNA fragments between A549 and A549 DDP cells were analyzed by mRNA differential display PCR(DD RT-PCR). The fragments thus obtained were further analyzed by DNA sequencing and Northern blotting. Results: Three differentially expressed cDNA fragments were obtained and confirmed by Northern blot. Sequence analysis revealed that two of them were novel and one was 100% identical with ICE gene. Conclusion: Analyzing differentially expressed fragment between A549 and A549 DDP cells may be helpful for finding new MDR related genes. The drug resistance of A549 DDP cells may be related to the inhibition or down-regulation of ICE gene.
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
