Mechanism of drug resistance and reversal with ligustra-zine and cyclosporin A in cisplatin--inducedhuman epithelial ovarian cancer resistant cell line 3Ao/cDDP

Objective: To investigate the mechanism of resistance and reversal effect of ligustrazine and cyclosporin A in cisplatin--induced multidrug resistance ovarian cancer cell line 3Ao/cDDP. Methods: Using the corresponding dose calculated from clinical chemotherapy at 30 mg cisplatin per cycle, we established 3Ao/cDDP with 3Ao exposed at regular intervals and repeatedly to high-level concentration of cisplatin at 10 mg/ml for 24 hours each time. Expressions of LRP, MRP, P-gp, GSTp and TopoII were quantitatively detected with FCM. For drug resistance reversal, cyclosporin A and ligustrazine were administered singly or in combination at the maximal dose without cytotoxicity. Inhibition rates were determined by MTT assay. Results: 3Ao/cDDP was established after 4.5 months, with resistance factor 1.6 which was similar to clinical resistance degree. Low expression levels of MRP and P-gp were found in both 3Ao and 3Ao/cDDP (P>0.05), and LRP and GSTp expression levels in 3Ao/cDDP were significantly higher than those in 3Ao (P<0.005 and P<0.05, respectively), and TopoII in 3Ao/cDDP was significantly lower vs 3Ao (P<0.05). The inhibition rate of cDDP was 20.807±0.015%, cDDP plus ligustrazine 27.421±0.07% (P>0.05 vs cDDP), cDDP plus cyclosporin A 49.635±0.021% (P<0.01 vs cDDP), and cDDP plus ligustrazine and cyclosporin A 58.861±0.014% (P<0.01 vs cDDP). Conclusions: 3Ao/cDDP, induced by cisplatin and established by imitating the characteristics of clinical chemotherapy for epithelial ovarian cancer, was an ideal model for investigation of cisplatin resistance in vitro. Cisplatin resistance in 3Ao/cDDP could be accounted for by higher LRP, GSTp and lower TopoII expression and was not associated with MRP or P-gp. Ligustrazine had no significant reversal effect on cisplatin resistance, but cyclosporin A could reverse the resistance effectively.

基于表型聚类和CDDP标记的牡丹花瓣色斑遗传多样性分析

【目的】采用色斑表型性状分析和保守DNA序列多态性(conserved DNA-derived polymorphism,CDDP)分子标记技术相结合的方法,揭示牡丹花瓣基部色斑的遗传起源。【方法】利用19个色斑表型性状和CDDP分子标记对191份牡丹材料的花瓣色斑进行遗传多样性分析,利用Origin软件进行表型性状变异分析和系统聚类,采用PopGene 2.4软件计算分子标记多样性指数和多态性位点率等,利用NTSYS软件非加权组平均法(UPGMA)绘制聚类树状图,并进行一致检测和Mantel检测。【结果】牡丹色斑表型变异分析结果表明:牡丹花瓣色斑性状发生了强变异,尤其是色斑颜色变异系数较大。表型性状聚类结果显示,紫斑牡丹与其他种或品种牡丹交集较多,且与西北牡丹品种关系最为密切。利用17条CDDP引物扩增191份牡丹材料的花瓣DNA,共扩增出401条条带,多态性位点率达到96.91%。在色斑群体水平上,有效等位基因数为1.3759,Nei’s基因多样性指数为0.2122,Shannon-Wiener信息指数为0.3324,说明牡丹花瓣色斑在分子水平上具有丰富的遗传多样性。聚类结果显示,紫斑牡丹和卵叶牡丹、四川牡丹聚在一起,三者亲缘关系较近,紫斑牡丹对现有牡丹栽培品种的色斑性状产生了较大影响,可能是牡丹品种色斑的主要来源。将表型性状聚类和CDDP分子标记聚类的遗传矩阵进行Mantel检验,得出相关系数为0.55,表明两种聚类结果有相似之处,均能很好地体现牡丹花瓣色斑的遗传来源。【结论】紫斑牡丹是牡丹品种色斑的主要来源,卵叶牡丹和四川牡丹也对牡丹品种色斑的形成有影响。

Cisplatin-induced activation of TGF-βsignaling contributes to drug resistance

Growing evidence suggests an association between epithelial-mesenchymal transition(EMT),a hallmark of tumor malignancy,and chemoresistance to a number of anti-cancer drugs.However,the mechanism of EMT induction in the process of acquiring anti-cancer drug resistance remains unclear.To address this issue,we obtained a number of cisplatin-resistant clones from LoVo cells and found that almost all of them lost cell-cell contacts.In these clones,the epithelial marker E-cadherin was downregulated,whereas the mesenchymal marker N-cadherin was upregulated.Moreover,the expression of EMT-related transcription factors,including Slug,was elevated.On the other hand,the upregulation of other mesenchymal marker Vimentin was weak,suggesting that the mesenchymal-like phenotypic changes occurred in these cisplatin-resistant clones.These mesenchymal-like features of cisplatin-resistant clones were partially reversed to parental epithelial-like features by treatment with transforming growth factor-β(TGF-β)receptor kinase inhibitors,indicating that TGF-βsignaling is involved in cisplatin-induced the mesenchymallike phenotypic changes.Moreover,cisplatin was observed to enhance the secretion of TGF-βinto the culture media without influencing TGF-βgene transcription.These results suggest that cisplatin may induce the mesenchymal-like phenotypic changes by enhancing TGF-βsecretion,ultimately resulting in drug resistance.

miR-125b reverses cisplatin resistance by regulating autophagy via targeting RORA/BNIP3L axis in lung adenocarcinoma

The platinum-based chemotherapy is one of the most frequently used treatment protocols for lung adenocarcinoma(LUAD),and chemoresistance,however,usually results in treatment failure and limits its application in the clinic.It has been shown that microRNAs(miRNAs)play a significant role in tumor chemoresistance.In this study,miR-125b was identified as a specific cisplatin(DDP)-resistant gene in LUAD,as indicated by the bioinformatics analysis and the real-time quantitative PCR assay.The decreased serum level of miR-125b in LUAD patients was correlated with the poor treatment response rate and short survival time.MiR-125b decreased the A549/DDP proliferation,and the multiple drug resistance-and autophagy-related protein expression levels,which were all reversed by the inhibition of miR-125b.In addition,xenografts of human tumors in nude mice were suppressed by miR-125b,demonstrating that through autophagy regulation,miR-125b could reverse the DDP resistance in LUAD cells,both in vitro and in vivo.Further mechanistic studies indicated that miR-125b directly repressed the expression levels of RORA and its downstream BNIP3L,which in turn inhibited autophagy and reversed chemoresistance.Based on these findings,miR-125b in combination with DDP might be an effective treatment option to overcome DDP resistance in LUAD.

Loss of Fascin2 increases susceptibility to cisplatin-induced hearing impairment and cochlear cell apoptosis in mice

Objectives:Deletion of Fscn2 gene in mice has been linked to progressive hearing loss and degeneration of cochlear cells.Cisplatin,an antitumor drug,can cause various side effects,including ototoxicity.The aim of this study was to investigate the effects of Fscn2 on cisplatin-induced hearing impairment in mice and to explore the possible mechanism.Methods:Two-week-old Fscn2+/+mice and Fscn2−/−mice were treated with two doses of cisplatin,with a 3-day recovery period in between.ABR(auditory evoked brain stem response)thresholds were measured and cochlear pathology was observed at 3 weeks of age.Results:Both Fscn2+/+and Fscn2−/−mice showed hearing loss under the effect of cisplatin,but the impairment was more severe in Fscn2−/−mice.Further experiments showed that the percentages of outer hair cell(OHC)and spiral ganglion neuron(SGN)loss were significantly higher in cisplatin-treated Fscn2−/−mice compared to Fscn2+/+mice.Additionally,knockdown of Fscn2 in HEI-OC1 cells worsened cisplatin-induced cell apoptosis.Conclusion:FSCN2 mediates reduction of CDDP induced ototoxicity by inhibiting cell apoptosis.

TGF-β-regulated different iron metabolism processes in the development and cisplatin resistance of ovarian cancer

The impact of different iron metabolism processes(DIMP)on ovarian cancer remains unclear.In this study,we employed various gene chips and databases to investigate the role of DIMP in the initiation and development of ovarian cancer.cBioPortal was used to determine mutations in DIMP-associated genes in ovarian cancer.Kaplan-Meier plotter was used to examine the influence of DIMP on the prognosis of ovarian cancer.By analyzing 1669 serous ovarian cancer cases,we identified a range of mutations in iron metabolism genes,notably in those coding for the transferrin receptor(19%),melanotransferrin(19%),and ceruloplasmin(10%)in the iron import process,and glucose-6-phosphate isomerase(9%),hepcidin antimicrobial peptide(9%),metal regulatory transcription factor 1(8%),and bone morphogenetic protein 6(8%)in the iron regulation process.Compared to the unaltered group,the group with gene alterations exhibited a higher tumor mutation burden count(43 vs.54)and more advanced histologic grade(78.19%vs.87.90%).Compared to the normal ovarian counterparts,a reduction in expression was observed in 9 out of the 14 genes involved in iron utilization and 4 out of the 5 genes involved in iron export in ovarian cancer;in contrast,an increase in expression was observed in 2 out of the 3 genes involved in iron storage in ovarian cancer.Furthermore,in cisplatin-resistant cells compared to cisplatin-sensitive ones,the expression of all genes in iron storage and 13 out of 14 genes in iron import was decreased,while that of 8 out of the 10 genes in iron utilization was increased.In addition,survival curve analysis indicated that a higher expression in the majority of genes in the iron import process(12/21),or a reduced expression in most genes in the iron export process(4/5)correlated with poor progression-free survival.Additionally,TGF-βcould regulate the expression of most iron metabolism-associated genes;particularly,expression of genes involved in the iron storage process(2/2)was inhibited after TGF-β1 or TGF-β2 treatment.In conclusion,DIMP plays multifaceted roles in the initiation,chemo-resistance,and prognosis of ovarian cancer.Therapeutically targeting DIMP may pave the way for more tailored treatment approaches for ovarian cancer.

Ganoboninketal C from Ganoderma boninense improves the efficacy of CDDP-based chemotherapy through inhibiting translesion DNA synthesis

Translesion DNA synthesis(TLS)can bypass DNA lesions caused by chemotherapeutic drugs,which usually result in drug resistance.Given its key role in mutagenesis and cell survival after DNA damage,inhibition of the TLS pathway has emerged as a potential target for improving the efficacy of DNA-damaging agents such as cisplatin(CDDP),a widely used anticancer agent.Unfortunately,few suitable natural TLS inhibitors have been reported.Here,we found that a triterpenoid compound Ganoboninketal C(26-3)from Ganoderma boninense,a traditional Chinese medicine,can impair CDDP-induced TLS polymerase eta(Polη)focus formation,PCNA monoubiquitination as well as mutagenesis.Moreover,26-3 can significantly sensitize tumor cells to CDDP killing and reduce the proportion of cancer stem cells in AGS and promote apoptosis after CDDP exposure.Interestingly,26-3 can also sensitize tumor cells to Gefitinib therapy.Mechanistically,through RNA-seq analysis,we found that 26-3 could abrogate the CDDP-induced upregulation of Polηand PIDD(p53-induced protein with a death domain),2 known factors promoting TLS pathway.Furthermore,we found that activating transcription factor 3 is a potential novel TLS modulator.Taken together,we have identified a natural TLS inhibitor 26-3,which can be potentially used as an adjuvant to improve clinical efficacy.

Celecoxib enhances the response of tumor cells to cisplatin through upregulating PUMA in non–small cell lung cancer carrying wild-type p53

Celecoxib,a cyclooxygenase-2 inhibitor,can enhance the efficacy of chemotherapy;however,its effect seems inconsistent.In this study,we investigated whether celecoxib would increase the antiproliferative effects of cisplatin in human lung cancer cells.Our data demonstrated the synergistic effects of celecoxib with cisplatin in wild-type p53 cells and their antagonistic effects inmutated or deleted p53 cells.Combination indices of 0.82 to 0.93 reflected a synergistic effect between celecoxib and cisplatin in lung cancer cells with wild-type p53.Combination indices of 1.63 to 3.00 reflected antagonism between celecoxib and cisplatin in lung cancer cells with mutated or deleted p53.Compared with that in cells with mutated or deleted p53,apoptosis significantly increased with the addition of celecoxib and cisplatin in wild-type p53 cells(P<0.05).Moreover,the results in vivo were similar to those in vitro:celecoxib combinedwith cisplatin slowed tumor growth in wild-type p53 groups and not in mutated or deleted p53 groups.In addition,celecoxib promoted p53 translocation into the nucleus and upregulated active p53 expression in wild-type p53 cells.Celecoxib combined with cisplatin upregulated PUMA(PUMA is a downstream gene of p53)after active p53 increased in wild-type p53 cells.In summary,the combination of celecoxib and cisplatin demonstrates clear synergistic effects in wild-type p53 cells and antagonistic effects inmutated or deleted p53 cells.The synergistic effect was achieved by apoptosis,induced by upregulating PUMA.Our results will provide a new treatment strategy for patients carrying wild-type p53,insensitive to cisplatin.

菊花品种的遗传多样性分析及CDDP指纹图谱构建

利用来源保守DNA序列多态性（CDDP）标记技术，探讨50个不同花径、瓣型、花色的菊花品种的遗传多样性。筛选的19条CDDP引物，共产生234个条带，平均每条引物产生12．32个条带，其中211个（90．17％）为多态性条带。菊花品种间的SM相似系数变化范围为0．6170～0．9447，平均0．7330。至少需要2条引物组合（WRKY-R2和WRKY-R3）可以完全区分50个品种。UPGMA聚类结果表明，所选的菊花品种基本按花径聚类，与瓣型和花色无直接关系。研究表明CDDP技术可有效用于菊花遗传多样性分析和品种鉴定研究。

大豆CDDP分子标记技术体系的优化、验证及引物筛选

CDDP分子标记是一种新型目的基因分子标记技术。采用L16(45)正交试验设计对影响大豆CDDP-PCR反应的Mg2+浓度、Taq DNA聚合酶用量、引物浓度、dNTPs浓度和模板DNA用量等因素进行优化。优化后的大豆CDDP-PCR体系为:Mg2+浓度2.0 mmol.L-1、Taq聚合酶用量1.5 U、引物浓度0.375μmol.L-1、dNTPs浓度0.3 mmol.L-1、DNA模板用量40 ng。该反应体系在16个大豆品种的验证中表现稳定可靠。利用大豆品种吉育75、本地黑豆及其9株F2代对该反应体系进行了初步的遗传验证,结果显示,杂交后代植株中出现了双亲的位点及亲本位点的缺失。并从21条引物中筛选出条带清晰、多态性较好的13条引物。该反应体系的建立为大豆种质遗传多样性分析、遗传连锁图谱构建及分子标记辅助育种奠定了基础。

利用CDDP标记的菏泽牡丹品种资源的遗传多样性

【目的】在品种群水平和花色群体水平上分析菏泽牡丹资源的遗传多样性和遗传分化,为该资源的保护和利用提供理论依据与技术支持。【方法】利用CDDP分子标记技术,对白、粉、黑、红、黄、蓝、绿、紫红、紫和复色系等10个花色群体构成的299份菏泽牡丹品种资源的基因组DNA进行扩增分析。【结果】用18条CDDP引物对10个花色群体共299份样品进行扩增,共检测到385条扩增带,其中多态性条带368条,特异条带23条,分别占总条带的95.58%和5.97%。在品种群水平上,Nei’s基因多样性指数、有效等位基因数和Shannon信息指数分别为0.1648、1.2569和0.2695;在花色群体水平上,上述指标依次为0.1451、1.2313和0.2306。综合分析各项指标得出,红色系和紫色系具有较高的遗传多样性,复色系和绿色系牡丹的遗传多样性较低。花色群体间的遗传距离较近,平均为0.0271;遗传一致度较高,平均为0.9735;遗传分化系数为0.1252,表明只有12.52%的遗传分化存在于群体间;群体间还具有较大基因流值(3.4939)。遗传多样性分析和UPGMA聚类结果在分子水平上验证了牡丹品种资源的花色演化趋势:以粉色系和红色系为中心,渐渐演化出紫红、紫、蓝和白色系,再进化为黄色系和黑色系,绿色系和复色系属于退化的色系。【结论】CDDP技术可有效揭示牡丹种质资源的遗传多样性。在品种群水平上,菏泽牡丹品种资源遗传多样性高于花色群体水平。花色群体间存在一定程度的遗传分化。聚类结果揭示了牡丹花色的演化趋势。

5-Aza-CdR与低浓度CDDP联合用药对胃癌细胞系生长及DAPK1的影响

目的研究5-Aza-CdR与低浓度CDDP联合用药对胃癌细胞系生长及DAPK1的影响。方法选择CDDP(1×10-6 mol/L)与1×10-6 mol/L的5-Aza-CdR分别处理体外培养的BGC823细胞与SCG7901细胞,5-Aza-CdR与CDDP联合处理体外培养的细胞后,用MTT法检测药物处理后的细胞增殖活性;RT-PCR法检测用药前后细胞中DAPK1的mRNA表达的变化。结果与单独用药组比较,胃癌细胞在药物联合作用组生长增殖活性明显被抑制。联合用药组DAPK-1基因的mRNA表达明显增加。结论 5-Aza-CdR与CDDP联用对胃癌细胞的生长抑制具有协同作用。

miRNA765高表达对胃癌耐药细胞株BGC-823/CDDP耐药性的影响

目的观察miRNA765高表达对胃癌顺铂(CDDP)耐药细胞株BGC-823/CDDP耐药性的影响。方法将PCR扩增的包含miRNA765前体的基因序列克隆至真核表达载体,构建miRNA重组表达载体;阳离子脂质体转染重组质粒到BGC-823/CDDP细胞。转染后48 h,Real-Time PCR和Western blotting法分别检测细胞中miRNA765和细胞因子诱导的凋亡抑制因子1(CIAPIN1)蛋白的相对表达量;采用不同浓度CDDP处理转染后48 h的BGC-823/CDDP细胞,24和48 h后MTT法检测细胞活性并计算细胞对于CDDP的半抑制浓度(IC50)。采用终质量浓度为1μg/mL的CDDP处理基因干预后的BGC-823/CDDP细胞,双染法检测细胞凋亡率。结果 BGC-823/CDDP细胞内miRNA765的相对表达量明显低于其亲本细胞BGC-823,CIAPIN1蛋白相对表达量则明显高于其亲本细胞株(均P<0.01)。在BGC-823/CDDP细胞内高表达miRNA765可明显抑制CIAPIN1蛋白的表达,转染后48 h的CIAPIN1蛋白表达量明显低于未转染组(P<0.01);miRNA765高表达可明显降低BGC-823/CDDP细胞的耐药能力,48 h后IC50值从(18.27±3.92)μg/mL降至(1.50±0.43)μg/mL(P<0.05)。转染48 h后,BGC-823/CDDP细胞的凋亡率从(10.1±1.7)%上升至(53.4±7.9)%(P<0.01)。结论 miRNA765高表达可以明显降低胃癌耐药细胞株BGC-823/CDDP的耐药能力。

芒果CDDP分子标记正交优化设计及引物筛选

以芒果基因组DNA为模板,选择正交设计试验对控制DNA保守序列多态性——聚合酶链式反应(CDDP-PCR)的4个因素(模板DNA浓度、dNTPs浓度、引物浓度、Mg^(2+)DNA聚合酶用量)进行正交试验,构建了较佳的芒果CDDP-PCR反应体系,含0.50 U Mg2+DNA聚合酶、0.40 mmol·L^(-1)d NTPs、1.00μmol·L^(-1)引物、0.50 ng·μL^(-1)模板DNA,加双蒸水使得总体积达20.00μL.对比四因子对PCR反应的影响,影响最强的因素是含Mg2+的DNA聚合酶,影响最弱的因素是模板DNA.利用供试的20个芒果品种验证了该体系的稳定性和可行性,21条CDDP引物均可扩增出明晰整齐的条带.

莪术油含药血清逆转胃癌SGC7901/CDDP多药耐药的研究

目的探讨莪术油含药血清对胃癌耐药细胞株SGC7901/CDDP的耐药逆转作用。方法血清药理法制备莪术油含药血清;MTT法检测莪术油含药血清对SGC7901/CDDP细胞的生长抑制作用;MTT法检测莪术油含药血清作用下化疗药对SGC7901/CDDP细胞生长抑制作用的变化,计算出莪术油含药血清的耐药逆转倍数。结果莪术油高、中剂量含药血清均可逆转SGC7901/CDDP细胞的耐药性(P<0.05),逆转倍数分别为6.06,2.61。结论莪术油含药血清可逆转胃癌耐药细胞株SGC7901/CDDP的耐药性,高剂量组莪术油含药血清的耐药逆转效果明显高于中剂量组,提示制备动物含药血清时,加大动物给药剂量可以增加逆转效果。

托瑞米芬逆转肺癌耐药细胞株A549/cDDP耐药性的研究

目的:探讨托瑞米芬(TOR)对耐顺铂(cDDP)细胞株A549的逆转作用,为临床应用提供实验数据。方法:用不同浓度的托瑞米芬单独及与cDDP联合与耐药细胞A549共同培养,通过MTT法和流式细胞仪法检测其对A549/cDDP的逆转及增敏效果。结果:经不同浓度的托瑞米芬单独及与cDDP联合与耐药细胞A549共同培养后,单独TOR(5μmol/L、10μmol/L)对A549/cDDP细胞的增殖均无明显影响,各组间数据无明显差异(P>0.05)。当cDDP与TOR联合作用时无论TOR终浓度5μmol/L或10μmol/L,均能明显增加cDDP对A549/cDDP细胞的敏感性(P<0.05,P<0.001)。其IC50值分别为39.06μmol/L和30.64μmol/L,逆转倍数分别为2.05倍和2.65倍。cDDP+TOR终浓度5μmol/L与cDDP+TOR终浓度10μmol/L之间除了在cDDP浓度为200μmol/L时两者有差异(P<0.05)外其它均无明显差异。结论:托瑞米芬与DDP联合应用可以提高A549/cDDP的逆转及治疗效果。

人肺腺癌耐药细胞株A549/CDDP中相关泛素化蛋白质研究

目的研究肺腺癌中与耐药相关的泛素化或类泛素化蛋白质及其与耐药的关系。方法从经顺铂处理和未处理的A549细胞及其耐顺铂细胞株中分离泛素化、类泛素化蛋白质,通过1D SDS-PAGE和Chip HPLC-MS/MS分析鉴别蛋白,Western blot法验证质谱结果;MTT法检测细胞对顺铂的耐药性。结果鉴定出发生类泛素化修饰蛋白质-PKM2,并发现其在耐药细胞株中低表达;以蛋白酶体抑制剂MG132干预细胞后,PKM2表达上调;CDDP和MG132联合作用细胞后,细胞耐药性下降。结论细胞中PKM2表达水平与肿瘤细胞耐药程度呈负相关,PKM2受蛋白质类泛素化修饰-SUMO化修饰调节,提示PKM2可能与肿瘤耐药的发生密切相关。

杧果品种亲缘关系的CDDP分析

利用保守DNA衍生多态性(CDDP)分子标记技术,对广西亚热带作物研究所保存的31个杧果品种进行遗传多样性分析,为杧果种质资源的鉴定及分子辅助育种提供理论依据。筛选出8条CDDP引物对供试的杧果品种进行PCR扩增,分析电泳图,并进行聚类分析和主成分分析。从31个杧果品种中共扩增出107条清晰条带,其中多态性条带(NPB)100条,多态性比率(PPB)达到93.57%。平均每条引物可扩增出13条带和12条多态性带。每个位点的平均等位基因数(Na)、有效等位基因数(Ne)、Nei's基因多样性(H)、Shannon信息指数(I)分别为1.8471、1.6368、0.4108、0.84,表明杧果品种间具有丰富的遗传多样性。供试杧果品种间相似性系数范围为0.6206~0.9208。UPGMA聚类结果表明,在遗传相似系数0.6906处可以将供试杧果划分为7类,主成分分析结果与聚类分析结果基本一致,划分结果与杧果来源地无密切关系。筛选获得的CDDP引物对杧果种质资源有较高的多态性检测率,适用于资源鉴别及亲缘关系分析。

沉默GST-π基因表达对EC9706/cDDP细胞顺铂耐药性的影响

目的:观察沉默谷胱甘肽S转移酶-π(GST-π)基因的表达对食管鳞状细胞癌顺铂耐药细胞系EC9706/cDDP细胞耐药性的影响。方法:构建靶向GST-π基因的siRNA重组慢病毒GSTsi1、GSTsi2和无义对照GSTsiC,转染EC9706/cDDP细胞。通过RT-PCR及Western blot法检测GSTsi1、GSTsi2和GSTsiC感染前后EC9706/cDDP细胞中GST-πmRNA和蛋白的表达;MTT法检测感染GSTsi2、GSTsiC与未感染的EC9706/cDDP细胞对顺铂敏感性的变化。结果:感染GSTsi1、GSTsi2后EC9706/cDDP细胞GST-πmRNA的表达下调(F=3.490,P<0.001),其蛋白表达也减弱。感染GSTsi2的EC9706/cDDP细胞对顺铂的耐药指数较感染GSTsiC和未感染的EC9706/cDDP细胞降低(F=50.510,P<0.001)。结论:沉默GST-π基因的表达可降低EC9706/cDDP细胞的顺铂耐药性。

肺癌细胞株中GEM和CDDP药物敏感性相关基因的研究

背景与目的筛选小细胞肺癌(small cell lung cancer,SCLC)和非小细胞肺癌(non-small cell lung cancer,NSCLC)细胞株中与健择(gemcitabine hydrochloride,GEM)和顺铂(cisplatin,CDDP)药物敏感性相关的基因,有助于进一步阐明抗癌药物作用机制,为克服抗癌药物的耐药性、研制开发新的抗癌药物提供新线索,同时也将为临床的个体化治疗提供理论依据。方法采用MTT比色分析法测定4株SCLC细胞株和6株NSCLC细胞株对CDDP和GEM的药物敏感性,同时应用cDNA macroarray技术检测10株肺癌细胞株中1291个药物敏感性相关基因的表达状态,分析二者之间的相关性。结果与GEM药物敏感性呈明显正相关(r≥0.632,P<0.05)的基因有6个;与CDDP药物敏感性关联的基因共有45个;与GEM、CDDP敏感性关联(r≥±0.4)的基因有41个;肺癌细胞系中与GEM和CDDP两类药物敏感性呈明显相关的基因是Metallothinein(信号转导分子)、CathepsinB(组织蛋白酶B)和TIMP1(生长因子);肺癌细胞系中与GEM、CDDP药物敏感性相关联的基因主要分布于Metallothinein、Cathepsin B、生长因子TIMP1等类别。结论SCLC和NSCLC细胞株中GEM、CDDP存在药物敏感性相关基因,其中Metallothinein、Cathepsin B和TIMP1基因与GEM药物敏感性呈正相关,与CDDP药物敏感性呈负相关。