Reversal effect of recombinant human Endostatin on cisplatin resistance in A549/DDP human lung adenocarcinoma cells in vitro

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.

榄香烯乳诱导线粒体凋亡途径逆转肺癌A549/DDP细胞株耐药

目的:探讨榄香烯乳(elemene,ELE)逆转人肺腺癌耐顺铂(cisplatin,DDP)细胞A549/DDP的耐药性及作用机制。方法:采用MTT法检测榄香烯乳单用的细胞毒作用及与DDP合用时耐药逆转作用。荧光探针JC-1结合激光共聚焦显微镜检测线粒体膜电位的变化。DCFH-DA荧光探针结合流式细胞仪检测细胞内活性氧(reactive oxygen species,ROS)水平。用谷胱甘肽试剂盒结合分光光度法检测计算GSH/(GSSG+GSH)比值。蛋白质印迹法检测胞质中Cyto C、Pro-caspase-3、Caspase-3和Bcl-2家族蛋白表达情况。结果:不同浓度榄香烯乳抑制A549/DDP细胞株生长,呈时间-剂量依赖性效应,联合顺铂能提高A549/DDP细胞株对顺铂的敏感性而逆转耐药。不同浓度榄香烯乳联合顺铂使A549/DDP细胞株线粒体膜电位下降,ROS浓度增加,GSH/(GSSG+GSH)比值降低,上调胞质中Cyto C、Caspase-3、Bad蛋白表达,下调Pro-caspase-3、Bcl-2蛋白表达。结论:榄香烯乳逆转A549/DDP细胞株耐药性可能与其损伤线粒体膜,活化胞内氧化还原体系,诱导线粒体凋亡路径有关。

榄香烯乳剂对肺癌A549/DDP细胞株耐药逆转作用及其机制

目的:探讨榄香烯乳(elemene,ELE)逆转人肺腺癌A549/DDP细胞株耐药性及其机制。方法:采用MTT法检测榄香烯乳单用的细胞毒作用及与顺铂(cisplatin,DDP)合用时耐药逆转作用;采用流式细胞术检测榄香烯乳对A549/DDP细胞内罗丹明-123(rhodamine-123,Rh123)蓄积的影响;采用Western blot检测榄香烯乳对耐药细胞A549/DDP细胞膜上P-gp蛋白表达的影响。结果:不同浓度榄香烯对A549/DDP细胞均有一定的抑制作用,呈时间-剂量依赖性效应。单用DDP的IC50为15.46μg/ml,合用20μg/ml榄香烯24h,IC50为4.15μg/ml,逆转耐药倍数为3.63。同时,榄香烯增加A549/DDP细胞内Rh123的蓄集,降低细胞膜上Pgp的表达,且呈剂量依赖性,表明榄香烯能减少A5 4 9/DDP细胞对药物的外排和抑制P-gp蛋白的表达。结论:榄香烯在体外逆转肿瘤细胞耐药性可能与其抑制P-gp的功能和表达有关。

三氧化二砷诱导A_(549)^(DDP)细胞株耐药基因表达的研究

目的：探讨三氧化二砷(As2O3）的耐药机制。方法：用四甲基偶氮唑蓝(MTT）法检测A_(549)^(DDP)细胞对As_2O_3的耐药性，用逆转录聚合酶链反应(RT－PCR）技术检测As_2O_3处理后A_(549)^(DDP) 细胞多药耐药基因(mdr1）及多药耐药相关蛋白(MRP）基因表达。结果：A_(549)^(DDP) 细胞对As_2O_3具有交叉耐药性。A_(549)和A_(549)^(DDP) 细胞中mdr1基因低表达，MRP基因呈较高水平表达。结论：A_(549)^(DDP) 细胞中MRP基因过度表达可能是As_2O_3耐药的主要机制之一。

补中益气汤含药血清对A549/DDP细胞生长周期作用的影响

目的评估补中益气汤含药血清对A549/DDP细胞生长周期的影响效果。方法体外培养人肺腺癌A549/DDP细胞,实验分组为:空白对照组,补中益气汤组和脾细胞处理组。用不同浓度的补中益气汤含药血清和脾细胞刺激A549/DDP细胞,采用MTT法(Methylthiazolyldiphenyl-tetrazolium bromide,MTT)测定2种方法对细胞的直接杀伤作用;流式细胞术检测2种方法对细胞凋亡的影响;荧光显微镜观察2种方法对凋亡小体产生的影响。结果MTT法显示同空白对照组相比,补中益气汤含药血清对细胞生长均有抑制作用(P<0.05),且该法同脾细胞作用后效果类似;2种方法处理后,流式细胞术均可见特征性的细胞凋亡峰;在荧光显微镜下可见凋亡细胞。结论补中益气汤含药血清在体外能阻滞A549/DDP细胞的生长增殖,诱导该细胞发生凋亡,且效果同脾细胞类似。

染料木素对非小细胞型肺癌A549/DDP细胞增殖和凋亡的影响

目的:观察染料木素(genistein)对人非小细胞型肺癌(non small cell lung cancer,NSCLC)A549/DDP细胞增殖和凋亡的影响。方法:培养A549及A549/DDP细胞株,以A549细胞为对照。①MTT法测定A549及A549/DDP细胞对顺铂的IC50值、耐药倍数及细胞增殖抑制率;②测定0、1.25、2.5、5.0、10、20、40、60、80μg/ml染料木素作用48 h对A549/DDP细胞增殖的抑制率及IC50值;③用6.25、12.5、25μg/ml染料木素处理A549/DDP细胞24 h后,经流式细胞计量仪检测细胞周期及细胞凋亡情况。结果:①A549及A549/DDP细胞对顺铂的IC50值分别为33.6μmol/L和76.9μmol/L,耐药倍数为2.3;细胞增殖抑制率随顺铂浓度增加而逐渐加大;②染料木素对A549/DDP细胞生长的影响,随染料木素浓度增加表现为先促增殖后抑制的作用,其对A549及A549/DDP细胞的IC50值分别为85.1μg/ml和80.2μg/ml;③6.25、12.5、25μg/ml染料木素作用于A549/DDP细胞24 h后,随染料木素浓度的增加,停留于G2/M期的细胞数逐渐增多(P<0.05),同时A549/DDP细胞出现凋亡。结论:染料木素可抑制A549/DDP细胞的生长,将细胞阻滞于G2/M期,并诱导细胞凋亡。

EXPRESSION AND REVERSION OF DRUG RESISTANCE-AND APOPTOSIS-RELATED GENES OF A DDP-RESISTANT LUNG ADENOCARCINOMA CELL LINE

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.

Influence of Tamoxifen or the combination of Tamoxifen and Cisplatin on the growth of human lung adenocarcinoma A549 cells

The experiment aims to investigate the influence of Tamoxifen and the combination of Tamoxifen and Cisplatin （DDP） on the growth of human lung adenocarcinoma A549 cells. Methods： We treated human lung adenocarcinoma A549 cells with different concentrations of Tamoxifen, DDP and combination of DDP and Tamoxifen with non-toxicity for 72 h. Then we calculated the inhibition rate through MTT approach and detected the apoptosis rate by flow cytometry. The statistical analysis was performed with SPSS 13.0 software and statistical differences were determined by one-way ANOVA. The data were expressed as the mean ＋ standard deviation and all experiments were performed in three times. The value of P 〈 0.05 was considered to indicate a statistically significant difference. Results： 1. The inhibition rates of Tamoxifen with 2.5 pmol/L, 5 tJmol/L, 10 μmol/L, and 20 μmol/L on the growth of the A549 cells were 18.7%, 25.8%, 54% and 98.8%, respectively （P = 0.000）. Tamoxifen with concentration of 1 μmol/L has no obvious cytoxicity on the A549 cells （P 〉 0.05）. 2. As the increase concentration of Tarnoxifen, the S stage and G2/M of the A549 cells decreased while the G0/G1 increased. The apoptosis rate of Tamoxifen with 0 μmol/L, 0.1 μmol/L, 1 μmol/L and 10 μmol/L on the A549 cells were 6.51%, 8.91%, 17.97% and 42.7%, respectively. 3. The inhibition rates of combination of Tamoxifen with 1 μmol/L and DDP with 1.25 μg/mL, 2.5 μg/mL, 5 μg/mL, 10 μg/mL and 20 μg/mL on the A549 cells were 40.4%, 54.4%, 72.9%, 86.1% and 92.4%, respectively （P 〈 0.05）. Conclusion： Tamoxifen can inhibit the proliferation of human lung adenocarcinoma A549 cells and induce the apoptosis of the A549 cells. The combination of Tamoxifen with non-toxicity and DDP can improve the sensitivity of chemotherapy on the A549 cells.

Empirical studies about quercetin increasing chemosensitivity on human lung adenocarcinoma cell line A549

Objective： The present study was designed to investigate whether quercetin exerts increasing chemosensitivity on human lung adenocarcinoma cells when quercetin combined with cisplatin （DDP） and vincristine （VCR） in vitro respectively and its possible antitumor mechanism. To provide experimental proof for clinical combination application. Methods： Using intermittent administration of high dose VCR, human lung adenocarcinoma sensitive cell line （A549/S） was induced to VCR- resistant human lung adenocarcinoma cell line （A549NCR）. MTT assay was adapted for examing the 50% inhibition （IC50） value of DDP and VCR on A549/S and A549/VCR when quercetin combined with DDP and VCR respectively. Results： IC50 of DDP on A549/S and A549/VCR was 10.18 and 12.35 mg/L, and the IC50 of VCR on the two cell lines was 1.21 and 12.77 rag/L, respectively. The resistance fold of A549/VCR on VCR and DDP was 10.55 and 121, respectively. When quercetin at concentration of 50, 100 and 200 pmol/L in combination with DDP and VCR respectively, the IC50 of DDP and VCR on A549/S and A549/VCR were obvious decreased （P 〈 0.05 - P 〈 0.01）. Conclusion： The experiment results suggested that quercetin could increase the chemosensitivity and partly revise the resistance of A549NCR.

The anti-cancer effect of Huaier aqueous extract with rh-Endostatin and DDP

Objective: The aim of our study was to explore the inhibition and apoptosis-inducing effect of the combination of Huaier aqueous extract with recombinant human Endostatin and DDP in human lung adenocarcinoma A549 cells. We also investigated the reversal effect of Huaier aqueous extract in reversing cisplatin resistance in human lung adenocarcinoma A549/DDP cells. Methods: We treated A549 cells with Huaier aqueous extract and the combination of Huaier aqueous extract and DDP or rh-Endostatin for 24 h, 36 h and 48 h. And then we calculated the inhibition rate through MTT approach and detected the apoptosis rate by flow cytometry. We also treated A549 and A549/DDP cells with DDP, Huaier aqueous extract, DDP and Huaier aqueous extract for 72 h, respectively. Results: Huaier aqueous extract can inhibit the growth of A549 cells and the inhibition rate improved with the increase of the concentration. The inhibition rate of the combination of rh-Endostatin and 4 mg/mL of Huaier aqueous extract in three time points and the combination of rh-Endostatin and 2 mg/mL of Huaier aqueous extract in the time point of 48 h on the growth of A549 cells all improved(P < 0.005). The inhibition rate of the combination of DDP and Huaier aqueous extract with the concentration of 2 mg/mL or 4 mg/mL on the growth of A549 cells all improved(P < 0.005). The combination of Huaier aqueous extract and DDP and the combination of Huaier aqueous extract with rh-Endostatin and DDP can improve the inhibition on the growth of A549 cells(P < 0.005). Conclusion: Huaier aqueous extract has the inhibition and apoptosis-inducing effects on the A549 cells. And the combination of Huaier aqueous extract and rh-Endostatin or DDP has the synergistic effects on the inhibition of A549 cells. The combination of Huaier aqueous extract with rh-Endostatin and DDP has the synergistic effects on the inhibition of A549 cells. Huaier aqueous extract can reverse the cisplatin resistance in human lung adenocarcinoma A549/DDP cells.

IDENTIFICATION OF DRUG RESISTANT RELATED cDNA IN LUNG ADENOCARCINOMA CELL LINES

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.

补中益气汤含药血清逆转人肺腺癌耐药细胞株A549/DDP耐顺铂作用及对Survivin表达的影响

目的研究补中益气汤含药血清逆转人肺腺癌耐药细胞株A549/DDP耐顺铂作用及对Survivin表达的影响。方法采用随机对照法将24只SD大鼠分为高、中、低剂量组和空白对照组,制备补中益气汤高剂量(补中益气汤1.134 g/mL,2 mL)、中剂量(补中益气汤0.576 g/mL,2 mL)、低剂量(补中益气汤0.284 g/mL,2 mL)含药血清,采用MTT法检测不同剂量和浓度的补中益气汤含药血清对A549及A549/DDP细胞的增殖抑制效应,计算耐药逆转倍数;采用免疫细胞化学法、Western blot技术、免疫荧光三种方法检测Survivin在两细胞株中的表达。结果补中益气汤含药血清对A549和A549/DDP细胞有明显抑制作用,10%各剂量组抑制率均高于5%相应剂量组,且随着剂量浓度的升高,抑制率也逐渐升高;与10%空白组比较,10%中、低剂量组抑制率升高(P<0.05);10%中剂量含药血清作用后,A549和A549/DDP IC50均降低(P<0.05),逆转倍数均升高,对A549/DDP细胞的逆转倍数达到2.46,使A549/DDP对顺铂的耐药性下降;与本组A549比较,免疫细胞化学法、Western blot法、免疫荧光法均检测到A549/DDP细胞中Survivin的表达量均降低(P<0.05),与10%空白组比较,10%中剂量组A549/DDP均降低(P<0.05)。结论 10%中剂量补中益气汤含药血清对A549及A549/DDP细胞都有抑制作用,并可逆转A549/DDP细胞的顺铂耐药,其逆转机制可能与减少细胞内Survivin的表达,增强A549/DDP对化疗药物的敏感性有关。

伊立替康及联合5-氟尿嘧啶、顺铂对人肝癌细胞株的细胞毒作用实验研究

[目的]探讨伊立替康(CPT-11)及联合5-氟尿嘧啶(5-FU)、顺铂(DDP)对人肝癌细胞株的细胞毒性作用。[方法]利用MTT比色法检测CPT-11,5-FU,DDP 3种药物对人肝癌HepG2细胞株的抑制率,进一步测定3种药物单药及联合用药对细胞生长抑制的情况并进行比较。[结果]不同浓度CPT-11,5-FU,DDP作用细胞后,细胞生长受到不同程度的抑制,这一抑制作用随药物浓度的升高而增强(P<0.01),单药对肝癌细胞株抑制作用最强的为CPT-11,其次为DDP,5-FU(三药作用于相同起始浓度的肝癌细胞株48、72、96、120 h后细胞数量分别为4.70±0.25、12.71±0.23、20.30±1.59、24.20±2.31;6.50±0.81、16.25±0.72、24.60±0.65、31.30±2.31;9.50±0.06、17.75±0.19、30.00±0.41、38.40±1.01;单位为1×104个/孔,与对照组比较P<0.01)。联合用药时抑制作用最强的为CPT-11、DDP、5-FU联合用药组,后依次为CPT-11、DDP联合、CPT-11、5-FU联合、5-FU、DDP联合(四组药物作用于相同起始浓度的肝癌细胞株48、72、96、120 h后细胞数量分别为6.30±0.79、9.50±0.66、14.50±0.03、21.40±0.66;6.60±0.54、12.20±0.71、20.90±0.45、28.80±0.36;9.00±0.61、16.40±0.29、30.40±0.37、37.30±0.25;12.00±0.02、18.80±0.39、30.70±0.07、35.40±0.08;单位为1×104个/孔,与对照组比较P<0.01)。[结论]CPT-11对肝癌细胞株具有一定的细胞毒性作用,并强于目前肝癌临床常规用药5-FU、DDP,CPT-11可与DDP、5-FU联合应用于原发性肝癌的治疗。

奥美拉唑逆转人肺腺癌耐顺铂细胞株A549/DDP耐药性的研究

目的:探讨液泡ATPase[vacuolar(H+)-ATPase,V-ATPase]非特异性抑制剂奥美拉唑(omeprazole,OME)逆转人肺腺癌耐药细胞株A549/DDP的耐药性及可能的作用机制。方法:以非细胞毒性浓度4μg/mL的OME预处理A549/DDP细胞24 h,再用2μg/mL顺铂(cisplatin,DDP)处理A549/DDP细胞。MTT法检测细胞的增殖抑制率,激光扫描共聚焦显微镜(laser scanning confocal microscope,LSCM)法间接检测细胞内pH值的变化,FCM法检测凋亡相关蛋白Bcl-2和PTEN的表达,RT-PCR法检测VATPase、Bcl-2和PTEN mRNA的表达。结果:OME具有逆转A549/DDP细胞耐药性的作用,逆转倍数为1.45(P<0.01);OME预处理后A549/DDP细胞内pH值明显降低,Bcl-2蛋白表达下降,PTEN蛋白表达增加(P<0.01)。V-ATPase在亲本A549及A549/DDP细胞中相对表达量分别为0.88±0.00和0.99±0.00(P<0.01);A549/DDP细胞中V-ATPase在有无OME预处理的情况下的相对表达量分别为1.09±0.00和1.05±0.02,差异无统计学意义。Bcl-2 mRNA相对表达量下降(P<0.01),PTEN mRNA相对表达量增加(P<0.01)。结论:V-ATPase在A549/DDP细胞中高表达,OME能部分逆转A549/DDP耐药性,其作用机制可能与上调PTEN和下调Bcl-2表达有关。

Co-transfection of MRP and bcl-2 antisense S-oligodeoxynucleotides reduces drug resistance in cisplatin-resistant lung cancer cells

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

肺腺癌细胞系耐药及凋亡相关基因的表达和逆转

目的 探讨顺铂耐药肺腺癌细胞系A549DDP的耐药、凋亡相关基因的表达及其与亲代细胞A549 的差异,观察差异表达基因的反义寡核苷酸的逆转作用。方法 将人工合成的反义、正义硫代脱氧寡核苷酸(Soligodleoxynucleotide ,SODN) 经脂质体包裹后转染A549DDP细胞,应用RTPCR 检测耐药及凋亡相关基因mRNA 水平,免疫细胞化学及流式细胞抗体(FCMIg) 检测相应蛋白及核增殖抗原Ki67 表达,MTT检测其耐药性改变,TUNEL、DNA 电泳检测细胞凋亡。结果 A549DDP细胞多药耐药基因( MDR1) 、拓朴异构酶Ⅱ(TOPOⅡ) 、cmyc mRNA 及蛋白表达水平接近A549 ,二者cerbB2 均阴性。A549DDPbcl2 阳性,且MRP mRNA 及蛋白水平较A549 高。bcl2 、MRP 反义SODN 可相应地抑制bcl2 、MRP、cmyc 表达,降低A549DDP耐药性,抑制其生长与增殖,促进细胞凋亡。结论 肺腺癌A549 细胞获得顺铂抗药性,与bcl2 和MRP基因高表达有密切关系。

组蛋白去乙酰化酶抑制剂联合顺铂对宫颈癌细胞凋亡作用的体外研究

目的:观察组蛋白去乙酰化酶抑制剂(SAHA)联合顺铂(DDP)对宫颈癌SiHa细胞生长抑制和促凋亡的效果。方法:以1μmol/L SAHA、2μmol/L SAHA、4μmol/L SAHA和1μg/ml、2μg/ml、4μg/ml DDP分别组成单药组和不同SA-HA+DDP联合用药组,分别应用MTT方法检测细胞增殖抑制率,应用流式细胞术检测SiHa细胞早期凋亡的情况。结果:联合用药组肿瘤细胞大量坏死明显,对细胞增殖的抑制率明显高于相应单药组(P<0.05);SAHA与中低剂量的DDP联合给药表现为协同作用,而与较高剂量的DDP联合用药表现为单纯相加作用;联合作用较二者单独用药细胞凋亡率明显增加(P<0.05)。结论:SAHA对宫颈癌细胞具有抑制增殖和促进凋亡的作用,SAHA联合DDP有协同增敏作用。