紫杉醇与吉非替尼对人肺腺癌细胞SPC-A1生长及细胞周期的作用

背景与目的既往研究显示,细胞毒化疗药物与表皮生长因子受体酪氨酸激酶抑制剂(EGFR-TKIs)吉非替尼同时使用治疗晚期非小细胞肺癌无临床获益。本研究观察紫杉醇与吉非替尼序贯应用对人肺腺癌细胞SPC-A1生长及细胞周期的影响,探索二者序贯用药是否比单药更有效及其可能的细胞学机制。方法RT-PCR法及Western blotting法分别检测SPC-A1细胞EGFRmRNA和蛋白表达,MTT法检测细胞增殖,流式细胞术检测细胞周期。结果SPC-A1细胞EGFRmRNA及蛋白呈过表达,在(1×10-14-1×10-6)M范围内,紫杉醇和吉非替尼均明显抑制SPC-A1细胞生长,作用呈浓度和时间依赖性。二者联合作用对细胞生长的影响与给药的次序有关:跟单药组比较,同时给药或先用吉非替尼后用紫杉醇组对抑制细胞生长无显著增强作用,先用紫杉醇后用吉非替尼组对抑制细胞生长有明显增强作用。细胞周期显示:紫杉醇和吉非替尼分别将SPC-A1细胞阻滞于G2期和G1期,同时用药组或先用吉非替尼后用紫杉醇组G1期细胞显著增多而G2期细胞显著减少,先用紫杉醇后用吉非替尼组G2期细胞显著增多而G1期细胞显著减少。结论紫杉醇和吉非替尼都能抑制SPC-A1细胞的生长,二者联合作用对细胞生长的影响与给药次序有关,同时给药或先用吉非替尼后用紫杉醇对抑制细胞生长无显著增强作用可能与它们对细胞周期的影响相关,先用紫杉醇后用吉非替尼对抑制细胞生长的增强作用可能与对细胞周期的影响无关。     

洛伐他汀克服非小细胞肺癌PC9细胞株吉非替尼耐药的体外研究

目的:研究联合洛伐他汀(lovastatin)和吉非替尼(gefi tinib)对体外诱导吉非替尼获得性耐药的非小细胞肺癌细胞株PC9细胞凋亡以及相关蛋白表达的影响,并探讨其可能的机制。方法:应用洛伐他汀联合吉非替尼处理耐吉非替尼的非小细胞肺癌PC9细胞株后,采用WST-1法检测不同药物处理对PC9细胞增殖的影响,Hoechst33342荧光染色法观察细胞凋亡形态,FCM法观察细胞凋亡状况,蛋白质印迹法检测凋亡相关蛋白的表达水平。结果:洛伐他汀联合吉非替尼可在体外诱导耐吉非替尼的PC9细胞凋亡,抑制其细胞增殖;洛伐他汀联合吉非替尼可诱导耐吉非替尼的PC9细胞中磷酸化表皮生长因子受体(phosphorylated epidermal growth factor receptor,p-EGFR)、磷酸化蛋白激酶B(phosphorylated protein kinase B,p-AKT)和磷酸化细胞外调节蛋白激酶1/2(phosphorylated extracellular signal-regulated kinase1/2,p-ERK1/2)蛋白表达水平明显下调。结论:在体外诱导吉非替尼获得性耐药的非小细胞肺癌细胞株PC9中,洛伐他汀可以克服吉非替尼耐药,两者具有良好的协同作用,提示两药联合对于出现吉非替尼耐药的非小细胞肺癌的临床治疗可能具有很大的应用潜力。     

大黄素逆转非小细胞肺癌EGFR-TKI耐药的机制研究

目的 探讨大黄素逆转非小细胞肺癌（NSCLC）表皮生长因子受体酪氨酸激酶抑制剂（EGFR TKI）耐药的作用机制。方法 应用持续诱导的方法构建NSCLC EGFR-TKI耐药细胞株HCC827／GR;应用MTS法检测大黄素（30μmol／L）、吉非替尼（1μmol／L）及两药联合处理HCC827和HCC827／GR细胞48h后细胞增殖能力的变化;应用Western blotting法检测HCC827和 HCC827／GR细胞中p EGFR、p-AKT、p-ERK1／2及p-MET蛋白表达水平的变化。结果 MTS法检测结果显示,经单药吉非替尼或大黄素处理后,HCC827／GR细胞增殖能力未减弱,而两药联合处理组的细胞增殖能力明显下降,差异有统计学意义（P＜0.05）。Western blotting检测结果显示,HCC827、HCC827／GR细胞中p-EGFR、p-ERK1/2明显表达,而p-AKT表达微弱;HCC827／GR 中p-MET表达水平较HCC827明显上调。经单药吉非替尼处理后,HCC827细胞株p-EGFR、p-ERK1/2表达水平下调,HCC827／GR细胞株p-EGFR表达明显下调;大黄素可显著下调HCC827／GR细胞株p-MET表达,但对p-EGFR、p-ERK1/2的表达无影响;而大黄素与吉非替尼两药联用可明显抑制HCC827／GR细胞株p-EGFR、p-ERK1/2以及p-MET的表达。结论 大黄素可以逆转NSCLC EGFR-TKI耐药,可能是通过抑制c-Met的活化来实现。     

吉非替尼联合培美曲塞对EGFR-TKI获得性耐药的非小细胞肺癌细胞的协同效应

目的:探讨培美曲塞联合吉非替尼对体外诱导的表皮生长因子受体-酪氨酸激酶抑制剂(epidermal growth factor receptor-tyrosine kinase inhibitor,EGFR-TKI)获得性耐药的人非小细胞肺癌PC9/吉非替尼耐药(gei tinib resistance,GR)细胞株的效应及其可能的机制。方法:吉非替尼和培美曲塞单药或联合作用于PC9/GR细胞后,MTT法检测各药物处理组细胞的增殖抑制率及药物的联合指数(combination index,CI),FCM法检测各组细胞的凋亡率,蛋白质印迹法检测各组细胞磷酸化AKT和Bcl-2蛋白的表达水平。结果:吉非替尼和培美曲塞联合应用对PC9/GR细胞的增殖抑制作用和促凋亡作用明显强于各单药组(P0.05);吉非替尼和培美曲塞的CI值1,表现出明显的协同效应。与未进行药物处理的对照组比较,培美曲塞联合吉非替尼可明显下调PC9/GR细胞中磷酸化AKT和Bcl-2蛋白的表达水平(P0.01)。结论:培美曲塞联合吉非替尼对PC9/GR细胞具有较好的协同作用,这协同作用可能与诱导细胞凋亡和下调磷酸化AKT蛋白表达有关。     

安罗替尼联合吉非替尼对吉非替尼耐药非小细胞肺癌PC9/GR细胞增殖的影响及其可能的作用机制

目的 探讨安罗替尼联合吉非替尼对吉非替尼耐药的人非小细胞肺癌PC9/GR（gefitinib resistance）细胞增殖的影响及其可能的作用机制。 方法 依据不同给药情况将PC9/GR细胞分为安罗替尼单药组、吉非替尼单药组、安罗替尼和吉非替尼联合用药组及阴性对照组,用MTT法检测各组细胞的增殖情况,流式细胞仪检测细胞的周期分布,Western blot检测p-ERK1/2和p-AKT蛋白的表达水平。 结果 安罗替尼和吉非替尼作用于PC9/GR细胞72 h的半数抑制浓度（half inhibitory concentration,IC₅₀）分别为（1.91±0.18） μmol/L和（4.83±0.15） μmol/L,两药均呈剂量依赖性的抗增殖作用,且两药联合时表现出明显的协同效应,联合指数（combination index,CI）小于1。安罗替尼和吉非替尼单药均可将PC9/GR细胞阻滞于G0/G1期（均P<0.05）。与各单药组比较,联合用药组表现出更明显的G0/G1期阻滞（均P<0.05）,且下调p-ERK1/2和p-AKT蛋白的表达水平（均P<0.05）。 结论 安罗替尼联合吉非替尼对非小细胞肺癌 PC9/GR细胞具有协同抗增殖作用,且可增强吉非替尼敏感性,其协同抗肿瘤机制可能与诱导细胞周期阻滞和下调p-ERK1/2和p-AKT蛋白的表达相关。     

吉非替尼与培美曲塞对人肺腺癌细胞 SPC - A1 生长及细胞周期的作用

目的：探索培美曲塞与表皮生长因子酪氨酸激酶抑制剂（EGFR—TKIs）吉非替尼联合应用对人肺腺癌细胞SPC—A1生长的影响,探索二者序贯用药是否比单药更有效,并从细胞周期角度分析其可能的细胞学机制。方法：RT—PCR法检测人肺腺癌细胞SPC—A1中EGFRmRNA表达,Westernblot法检测SPC—A1细胞中EGFR蛋白表达,四甲基偶氮唑盐[3-（4,5-dimethylthiazol-2-y1）-2,5-diphenyl—tetrazoliumbro—mide,M1Tr]显色分光光度法检测细胞增殖,流式细胞术检测细胞周期。分别观察培美曲塞与吉非替尼单独、同时及间隔24小时序贯作用。结果：SPC—A1细胞中有EGFRmRNA和蛋白的表达,且其表达量为过表达。吉非替尼和培美曲塞分别在0．1pmol/L-1umoL／L和109-10-1g/L浓度范围内明显抑制SPC—A1细胞生长,呈浓度依赖性,IC50分别为：61．2nml/L（吉非替尼）和16．2ug/ml（培美曲塞）,二者在IC50下抑制作用呈时间依赖性,96h时达最大抑制。二者联合作用于细胞时对生长的影响与二者加药的次序有关,跟单药组相比,先用培美曲塞后用吉非替尼组对抑制细胞生长有明显增强作用（P〈0．05）,同时给药或先用吉非替尼后用培美曲塞组对抑制细胞生长无显著增强作用（P〉0．05）。细胞周期研究显示：吉非替尼和培美曲塞作用于不同的细胞周期,分别将SPC—A1细胞阻滞于G,期（G0／G1）和S期,先用吉非替尼后用培美曲塞组G1（G0／G1）期细胞显著增多,G2期（G2／M）细胞显著减少（P〈0．05）。同时用药组G1期（G0／G1）和s期细胞比例无显著变化,G2期（G2／M）细胞显著增多（P〈0．05）。先用培美曲塞后用吉非替尼组G1期（G0／G1）细胞显著减少,s期细胞比例无显著变化,G2期（G2／M）细胞显著增多（P〈0．05）。结论：吉非替尼和培美曲塞都能抑制SPC—A1细胞生长,二者联合作用对细胞生长的影响与给药次序有关,先用吉非替尼后用培美曲塞对抑制细胞生长无显著增强作用,而先用培美曲塞后用EGFR—TKIs则表现有明显的协同性,且这种关系可能与它们对细胞周期的影响相关。     

培美曲塞和吉非替尼不同时序应用对人肺腺癌细胞的作用和机制

目的 探讨培美曲塞与吉非替尼不同时序应用对肺腺癌细胞A549和PC-9生长及凋亡的影响, 并阐述其可能机制。方法 MTT法检测各组细胞的增殖抑制情况,流式细胞仪检测各组细胞凋亡及细胞周期分布,Western印迹法检测对EGFR下游信号通路及TS酶蛋白水平表达的影响。结果 培美曲塞序贯吉非替尼、培美曲塞同步联合吉非替尼对PC-9和A549细胞增殖抑制率及凋亡率较单药组均提高（P<0.05）,培美曲塞可以提高EGFR、AKT 、ERK磷酸化水平,而吉非替尼表现为抑制作用, 同时吉非替尼降低TS酶表达。培美曲塞序贯吉非替尼,培美曲塞同步联合吉非替尼抑制EGFR、AKT 、ERK磷酸化水平较单药更强。吉非替尼主要将PC-9、A549细胞阻滞在G0/G1期;培美曲塞主要将细胞阻滞在S期。培美曲塞序贯吉非替尼、培美曲塞同步联合吉非替尼较其他组G2/M期细胞比例提高（P<0.05）。结论 培美曲赛序贯吉非替尼、培美曲赛同步联合吉非替尼在PC-9、A549细胞中均起到协同增效作用,且培美曲赛序贯吉非替尼协同作用更为显著,可能主要与培美曲赛诱导EGFR、AKT 、ERK磷酸化及吉非替尼降低TS酶作用有关。     

肺岩宁方联合吉非替尼抑制肺癌裸鼠移植瘤细胞H1975生长及其作用机制

目的 观察肺岩宁方联合吉非替尼对肺腺癌裸鼠移植瘤细胞H1975生长的影响并探讨其可能的作用机制。方法 成功建立H1975细胞裸鼠皮下移植瘤模型后,随机分为模型组、吉非替尼组、肺岩宁方组及联合用药组,每组10只,分别用相应药物干预4周,检测肿瘤体积、瘤重、体重等,绘制肿瘤生长曲线,计算肿瘤抑制率;应用TNUEL法检测移植瘤细胞凋亡;应用Westernblot法检测EGFR-PI3K/AKT信号通路相关蛋白表达。结果 各组的抑瘤率模型组为0,吉非替尼组21.91%,肺岩宁方组25.11%,联合用药组53.28%;各组移植瘤组织中肿瘤细胞的凋亡率分别为模型组（15.11±1.6）%,吉非替尼组（26.64±0.69）%,肺岩宁方组（28.88±1.61）%,联合用药组（55.06±2.39）%。联合用药组与模型组及单用吉非替尼、肺岩宁方相比差异有统计学意义（P<0.01）。Western blot结果显示肺岩宁方联合吉非替尼在不影响EGFR、AKT、mTOR总蛋白表达的情况下,可显著下调p-EGFR、p-AKT、p-mTOR水平。结论 肺岩宁方联合吉非替尼可显著抑制H1975肺癌裸鼠移植瘤的生长,促进肿瘤细胞凋亡,其作用机制可能与阻断EGFR-PI3K/AKT信号通路有关。     

吉非替尼联合AG1024抑制结肠癌细胞生长的体外研究

目的:探讨抑制表皮生长因子受体(EGFR)、胰岛素样生长因子1型受体(IGFR-1)活性对不同结肠癌细胞下游信号通路的影响及其产生的细胞生长抑制效应.方法:选择对EGFR抑制剂吉非替尼敏感性不同的结肠癌细胞,给予IGFR-1酪氨酸激酶抑制荆AGl024和吉非替尼单独或联合作用,以蛋白质印迹法检测EGFR、IGFR-1β及其下游信号蛋白AKT、MAPK表达和活性,以MTT法检测细胞增殖率.结果:LOVO细胞(吉非替尼敏感型)在吉非替尼作用下AKT、MAPK活性被抑制,P＜0.05,而不论是否与AG1024联合;HT29细胞(吉非替尼中度敏感型)在吉非替尼和AG1024单独作用下AKT、MAPK活性均抑制不明显,而联合作用则其活性显著被抑制,P＜0.05;HCT116细胞在AG1024作用下AKT、MAPK活性被抑制,P＜0.05,而不论是否与吉非替尼联合.细胞增殖率显著降低见于吉非替尼作用下的LOVO细胞、吉非替尼联合AG1024作用下的HT29细胞以及AG1024作用下的HCT116细胞(P＜0.05).结论:吉非替尼联合AG1024可阻断下游信号通路的持续活化,在一定程度上可以改善结肠癌细胞对吉非替尼生长抑制作用的耐受.     

IGF-1R抑制剂联用可增强人非小细胞肺癌PC9/G细胞对吉非替尼的敏感性

目的:观察单用表皮生长因子受体(epidermal growth factor receptor, EGFR)的酪氨酸激酶抑制剂吉非替尼 (ge? tinib) 或联合胰岛素生长因子-1受体(insulin-like growth factor-1 receptor,IGF-1R)的酪氨酸激酶抑制剂AG1024作用于人非小细胞肺癌耐药株PC9/G细胞后,该细胞对吉非替尼耐药性的影响,并探讨IGF-1R与肿瘤细胞耐药的相关机制。方法:用吉非替尼和AG1024单独或联合作用于PC9/G细胞后,采用MTT法分别检测各组细胞的增殖情况,并利用中效原理判断两药联用的效果;FCM法检测各组细胞的凋亡情况;Western印迹法检测各组细胞的磷酸化EGFR(phosphorylated EGFR, p-EGFR)、磷酸化Akt(phosphorylated Akt,p-Akt)和磷酸化细胞外信号调节激酶(phosphorylated extracellular signal-regulated kinase,p-ERK)的表达水平。结果:吉非替尼和AG1024单独作用于PC9/G细胞后,均出现不同程度的细胞增殖抑制作用和细胞凋亡促进作用;而吉非替尼和AG1024联合作用,能更显著地抑制细胞增殖,且凋亡细胞显著增加(P<0.05)。 Western印迹法检测发现,联合用药组的p-EGFR、p-Akt和p-ERK蛋白表达量明显减少。结论:IGF-1R抑制剂AG1024和EGFR抑制剂吉非替尼联用具有较好的协同作用,可能通过抑制细胞增殖和促进细胞凋亡,提高耐药细胞对吉非替尼的敏感性。     

Gefitinib inhibits the growth and invasion of urothelial carcinoma cell lines in which Akt and MAPK activation is dependent on constitutive epidermal growth factor receptor activation.

PURPOSE: Abnormally high levels of epidermal growth factor receptor (EGFR) protein are associated with advanced tumor stage/grade. The objective of this study was to evaluate the effects of the specific EGFR tyrosine kinase inhibitor gefitinib on activation of the Akt and mitogen-activated protein kinase (MAPK) pathways in human urothelial cell carcinoma (UCC) cell lines and to identify potential markers of gefitinib responsiveness in biopsy samples of UCC. EXPERIMENTAL DESIGN: Changes in markers of UCC growth and invasion after exposure to gefitinib were studied in six human UCC cell lines expressing various levels of EGFR. The findings were related to activation of Akt and MAPK. We studied the influence of gefitinib on intraepithelial expansion of the responsive 1207 cell line. EGFR, Akt, and MAPK activation was studied by Western blot analysis of a panel of 57 human UCC. RESULTS: Gefitinib had a growth-inhibitory and anti-invasive effect in two of six UCC cell lines (i.e., 647V and 1207). Gefitinib was also able to block the expansion of 1207 at the expense of normal urothelial cells. These effects did not depend on the level of expression of EGFR but they were associated with the down-regulation of MAPK and Akt activity; in 1207 cells, gefitinib activity was associated with p27 up-regulation and p21 and matrix metalloproteinase-9 down-regulation. Similarly, the Akt and MAPK pathways were found to be strongly phosphorylated in association with EGFR activation in a subset of human UCC specimens. CONCLUSIONS: Activation of EGFR, Akt, and MAPK defines a subset of UCC which might provide information for the identification of gefitinib responders.     

The Effect of the EGFR - Targeting Compound 3-[(4-Phenylpyrimidin-2-yl) Amino] Benzene-1-Sulfonamide (13f) against Cholangiocarcinoma Cell Lines

Objective: Cholangiocarcinoma (CCA) is a noxious malignancy of epithelium of the bile duct with a low response rate to chemotherapy. The epidermal growth factor receptor (EGFR) signaling pathway is implicated in the development of cancerous cells, especially CCA. In this study, we report detailed biological profiling of 13f identified from our earlier hit expansion studies. The aim of this work was to expand our understanding of 13f via more detailed investigations of its mechanism of action against KKU-100, KKU-452 and KKU-M156 CCA cells, as well as in comparison to the EGFR inhibitor Gefitinib and non-specific chemotherapeutic agents such as Cisplatin. Methods: Inhibiting EGFR-Kinase, cytotoxicity, clonogenic assay, wound healing and apoptosis were performed. Levels of total expression of EGFR and EGFR phosphorylation proteins were detected. Results: 13f was confirmed as an inhibitor of EGFR with an IC50 value against the tyrosine kinase of EGFR of 22 nM and IC50 values for 48 h incubation period were 1.3 ± 1.9, 1.5 ± 0.4 and 1.7 ± 1.1 µM of KKU-100, KKU-452 and KKU-M156, respectively through dose- and time-dependent induction of early apoptosis of CCA cells. The compound also suppressed the clonogenic ability of KKU-100 and KKU-M156 cells stronger than Gefitinib, while potently inhibiting EGF-stimulated CCA cell migratory activity in KKU-452 cells. It was observed that under normal conditions EGFR was activated in CCA cells. EGF-stimulated basal expression of EGFR in KKU-452 cells was suppressed following 13f treatment, which was significantly greater than that of the marketed EGFR inhibitor Gefitinib. Conclusion: In summary, our study showed that 13f has potent anti-cancer activities including antiproliferation, clonogenic ability and migration through the modulation of EGFR signaling pathway in CCA for the first time. The compound represents an interesting starting point as a potential chemotherapeutic agent in ongoing efforts to improve response rate in CCA patients.     

吉非替尼对胃癌细胞株放射增敏的作用

背景与目的:表皮生长因子受体(epidermal growth factor receptor,EGFR)在绝大部分人类上皮肿瘤中都有表达,其表达高低与放疗抗拒有关.我们检测EGFR酪氨酸激酶抑制剂吉非替尼(gefitinib)对高表达胃癌细胞株放射增敏的作用,并初步探讨其机制.方法:Western blot法测定7株人胃癌细胞株(MKN45、SGC7901、SNU-1、N87、AGS、SNU-16、KATO-Ⅲ)中EGFR蛋白的表达,选取2株EGFR相对高表达的胃癌细胞用于后续实验.采用MTT法测定吉非替尼的半数抑制浓度(50%inhibition concentration,IC50),克隆形成实验计算细胞存活率,拟合生存曲线并计算放射生物学参数,流式细胞仪检测吉非替尼联合放疗的凋亡率及细胞周期分布.结果:选取7株胃癌细胞中EGFR表达最高的MKN45和SGC7901细胞,发现其存活率均随吉非替尼浓度或放射剂量的增加而明显下降(P＜0.05).MTT法检测吉非替尼对MKN45及SGC7901细胞的IC50分别为0.4mmol/L和0.8 mmol/L.MKN45细胞在0.1×IC50及0.2×IC50剂量下的增敏比(SER)分别为1.102和1.154,SGC7901则为1.092和1.176.吉非替尼或照射均可增加凋亡率,减少S期细胞比例及增加G2/M期细胞比例(P＜0.01).结论:吉非替尼序贯照射应用可提高EGFR高表达胃癌细胞的放射敏感性并阻碍细胞增殖、促进凋亡和干扰细胞周期分布.吉非替尼有望成为EGFR高表达胃癌的放射增敏剂.     

BIM induction of apoptosis triggered by EGFR-sensitive and resistance cell lines of non-small-cell lung cancer

We sought to improve the understanding of oncogene-dependent and independent non-small-cell lung cancer (NSCLC), which could provide insight into mechanism of sensitivity and/or resistance to tyrosine kinase inhibitors or chemotherapeutics. NSCLC cell lines with different EGFR genotypes were used in this study; MTT assay and flow cytometry were applied to study the sensitivities of these cell lines to gefitinib and cisplatin. Western blot was performed to determine the expression levels of BIM and other Bcl-2 family proteins pre- and pro-treatment. Gefitinib provoked apoptosis of caspase activation via the intrinsic pathways and significantly up-regulated expression of BIM protein in drug-sensitive PC-9 cell line, but not resistant PC-9/BB4 cell line. The knockdown of BIM expression by RNA interference virtually eliminated gefitinib-induced cell killing in PC-9 cells in vitro. Cisplatin could induce apoptosis of the cell lines, including H1299, A549, PC-9, and PC-9/BB4 cells, but which was not associated with overexpression of BIM. BIM is involved in TKI-induced apoptosis in sensitive EGFR-mutant cell line. Down-regulation of BIM and resistance to gefitinib were both seen in the acquired resistant PC-9/BB4 cell line. The induction of BIM may have a role in the treatment of TKI-resistant tumors.     

Gefitinib (ZD1839) increases the efficacy of cisplatin in ovarian cancer cells

We examined the effect of gefitinib (ZD1839), a selective epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor, on cytotoxicity to cisplatin, EGFR downstream signaling, apoptosis and the association between the inhibition of DNA repair by gefitinib and the expression of DNA-dependent protein kinase (DNA-PK) using three ovarian cancer cell lines. In the presence of gefitinib, cisplatin-induced growth inhibition and apoptosis were significantly enhanced in Caov-3 and RMG-1 cells, which express EGFR, and in A2780, which lacks EGFR but expresses HER-2. Gefitinib significantly inhibited the cisplatin-induced ERK and Akt activation in Caov-3 and RMG-1 cells but not in A2780 cells. In all three cell lines, there was delayed repair of DNA intrastrand cross-links damaged by cisplatin used in combination with gefitinib, compared with cisplatin alone. The reduction in DNA-PK levels persisted when cells were exposed to combinations of cisplatin and gefitinib in all cell lines. Moreover, the delayed repair was cancelled by anti-HER2 small-interfering RNA transfection in A2780 cells. These results suggest that combination therapy with cisplatin and gefitinib may increase the therapeutic efficacy of cisplatin by blocking EGFR downstream signaling and/or inhibiting DNA repair in ovarian cancer.     

ATM蛋白在不同放射敏感性鼻咽癌细胞株中的表达

背景与目的:ATM(Ataxia-telangiectasiamutant)蛋白与细胞放射敏感性密切相关。本研究探讨ATM蛋白在具有不同放射敏感性的鼻咽癌细胞系CNE1,CNE2中的表达。方法:采用免疫荧光标记技术,对CNE1、CNE2中的ATM蛋白进行激光扫描共聚焦显微镜(LSCM)分析。结果:ATM蛋白定位于细胞核及胞浆中,并以细胞核为主,且CNE1细胞核中ATM蛋白阳性细胞的荧光强度较CNE2强;半定量分析,CNE1中ATM蛋白表达的积分吸光度值为9×106,CNE2中为3×106。结论:ATM蛋白的表达在CNE1、CNE2中有差别,这种差别可能与它们所具有的不同放射敏感性有关。     

顺铂对鼻咽癌细胞NKG2D配体表达和NK细胞杀伤活性的增强作用

 目的 研究顺铂(Cisplatin, DDP)作用前后人鼻咽癌细胞CNE2 NKG2D配体和HLA-Ⅰ类分子表达的改变及NK细胞杀伤活性的变化。 方法 MTT法测定DDP对CNE2细胞的50%抑制量（IC₅₀）;以此浓度DDP作用CNE2细胞24h,乳酸脱氢酶释放法检测效靶比20∶1时,NK细胞对DDP作用前后的CNE2细胞的杀伤活性;流式细胞仪检测DDP作用前后的CNE2细胞表面NKG2D配体(MICA/B、ULBP1、ULBP2、 ULBP3)和HLA-Ⅰ类分子表达的变化。 结果 DDP对CNE2细胞的IC₅₀为5mg/L。效靶比20∶1时,NK细胞对5mg/L DDP作用前后的CNE2细胞的杀伤活性分别为 （38.11±1.41）%,（47.71±1.53）%,差异有统计学意义（P＜0.05）,DDP作用后CNE2细胞表面MICA/B、ULBP1、 ULBP3表达显著升高,与作用前相比差异有统计学意义（P＜0.05）。ULBP2、HLA-Ⅰ类分子无明显变化(P＞0.05)。 结论 DDP能提高CNE2细胞NKG2D配体(MICA/B、ULBP1、ULBP3)的表达,从而增强CNE2细胞对NK细胞杀伤的敏感度。     

EB病毒潜伏膜蛋白1对鼻咽癌细胞系CNE1有丝分裂调控机制的影响

EB病毒潜伏膜蛋白(latent membrane protein l,LMPl)是被证实在鼻咽癌中具有癌基因功能的病毒编码基因的表达产物;LMPl参与异常的细胞周期调控,但是否导致有丝分裂检测点调控机制紊乱仍未得到实验证实。本实验观察LMPl对鼻咽癌细胞株CNEl有丝分裂调控的影响,进一步探讨LMPl在鼻咽癌发病机制中的作用。     

EBV-LMP1对鼻咽癌细胞系CNE1细胞转移相关因素的影响

背景与目的:已证实EB病毒(Epstein-Barrvirus,EBV)编码的潜伏膜蛋白1(latentmembraneprotein1,LMP1)能够诱导鼻咽癌细胞中基质金属蛋白酶9(matrixmetalloproteinase-9,MMP-9)的表达。本实验的目的是观察EB病毒潜伏膜蛋白1(EBV-LMP1)对鼻咽癌细胞系CNE1细胞转移相关因素的影响,探讨LMP1在鼻咽癌侵袭、转移过程中的作用。方法:用免疫组化法及Westernblot法检测CNE1-GL(转染LMP1基因的CNE1细胞)和CNE1细胞中MMP-9的表达情况;用细胞-基质粘附实验、细胞运动实验和肿瘤细胞重组基底膜侵袭实验检测LMP1对CNE1细胞粘附、运动及侵袭能力的影响。结果:免疫组化法及Westernblot法结果均显示CNE1-GL细胞中MMP-9的表达明显高于CNE1细胞(P<0.05);肿瘤细胞-基质粘附实验结果显示,CNE1-GL的粘附能力(平均吸光度值为1.2508±0.0711),高于CNE1细胞(平均吸光度值为0.9519±0.068),两者相比差异有显著性(P<0.01)。运动实验及重组基底膜侵袭实验结果均显示,穿过游离的聚乙烯吡咯烷酮膜(polyvinylpyrroli-done-free,PVP-F)的CNE1-GL细胞数明显高于CNE1细胞(P<0.01)。结论:LMP1能够诱导CNE1细胞中MMP-9的表达,且增强CNE1细胞与基底膜的粘附能力、运动能力及侵袭能力。