灵芝多糖对顺铂诱导卵巢癌细胞耐药株的逆转

目的 探讨灵芝多糖对卵巢癌耐药细胞SKOV-3/DDP耐药逆转的作用及机制.方法 (1)采用浓度递增法建立人卵巢癌DDP耐药细胞系SKOV-3/DDP,用MTT法、光学显微镜和透射电子显微镜验证实验结果.(2)采用MTT比色法检测灵芝多糖和顺铂连续用药(灵芝多糖作用12 h后,加入顺铂作用12 h)及灵芝多糖和顺铂联合用药对SKOV-3/DDP细胞的生长抑制作用.结果 成功建立了SKOV-3/DDP耐药株,其耐药指数为6.02.灵芝多糖和顺铂连续用药对SKOV-3/DDP细胞的抑制率为32.3%,灵芝多糖和顺铂联合用药对SKOV-3/DDP细胞的抑制率为23.1%.结论 灵芝多糖不仅均有抗肿瘤的作用,还能改善肿瘤细胞的耐药性,增强其对化疗药物的敏感性.     

香菇多糖加顺铂治疗恶性胸腔积液疗效观察

近年来，我们采用香菇多糖、顺铂治疗恶性胸腔积液，取得较好疗效。现报告如下。     

胸腔内注射顺铂及香菇多糖治疗老年恶性胸腔积液的临床观察

目的观察胸腔内置管注入顺铂和香菇多糖治疗老年恶性胸腔积液的疗效。方法老年恶性胸腔积液68例,随机分为两组,治疗组经皮胸腔内置管引流尽胸液后,胸腔内注入顺铂和香菇多糖,对照组予顺铂注入胸腔。每周复查胸水情况,观察疗效及不良反应。结果治疗组总有效率为73.5%,高于对照组52.9%,差异有统计学意义（P〈0.05）。两组均有发热、恶心、呕吐、外周血白细胞减少等不良反应,但差异无统计学意义。结论胸腔内注入顺铂和香菇多糖治疗老年恶性胸腔积液疗效好且安全。     

胸腔内注射香菇多糖联合顺铂治疗肺癌并发恶性胸腔积液的观察

目的 观察香菇多糖联合顺铂胸腔内注射治疗肺癌并发恶性胸腔积液的疗效和不良反应.方法 选择肺癌并发恶性胸腔积液行胸腔闭式引流患者52例,观察组24例行胸腔内注射顺铂和香菇多糖,对照组28例单用顺铂,每周1次.结果 观察组有效率为75.0％,高于对照组的53.6％,两组比较差异有统计学意义(P＜0.05);观察组生活质量改善率为66.7％,高于对照组的50.0％,两组比较差异有统计学意义(P＜0.05).观察组不良反应较对照组轻.结论 香菇多糖联合顺铂胸腔内注射治疗肺癌并发恶性胸腔积液,疗效肯定,不良反应轻.     

顺铂联合香菇多糖胸腔内注射对老年肺癌伴胸腔积液的疗效分析

目的 观察顺铂联合香菇多糖胸腔内注射对老年肺癌伴胸腔积液的疗效.方法 选择老年肺癌性胸腔积液患者80例,随机分成观察组（顺铂联合香菇多糖）和对照组（顺铂）各40例.在经皮胸腔内置管引流尽胸液之后,进行胸腔内注药,观察疗效.结果 观察组和对照组的总有效率分别为92.50%和62.50%,生活质量改善率分别为87.50%和65.00%,P〈0.05.结论 顺铂联合香菇多糖胸腔内注射对老年肺癌伴胸腔积液具有较好疗效,不良反应少.     

五味子粗多糖与顺铂抑制脑胶质瘤细胞增殖的作用

目的研究五味子粗多糖(FSP)单独或与顺铂联合抑制脑胶质瘤细胞增殖的作用。方法培养脑胶质瘤(SHG-44)细胞,应用四甲基偶氮唑(MTT)法检测FSP单独及联合顺铂抑制细胞增殖的情况。结果脑胶质瘤SHG-44细胞在FSP浓度200、400、800μg/ml时,均可以抑制细胞的增殖(P<0.05或P<0.01),且有浓度依赖性。FSP与顺铂联合作用时可以明显地抑制细胞的生长(P<0.01)。结论 FSP可以抑制胶质瘤SHG-44细胞的增殖,联合顺铂时可发挥协同作用。     

抑制端粒酶活性能增加胃癌细胞对顺铂的敏感性

肿瘤细胞存在多药耐药现象和化疗药物的毒副作用是影响肿瘤化疗效果的主要原因。新近研究表明 ,表达于绝大多数肿瘤细胞而不表达于正常体细胞的端粒酶与化疗敏感性有关[1,2 ] 。在我们既往研究工作的基础上 ,我们观察了反义人端粒酶ＲＮＡ(ｈＴＲ)转染的ＳＧＣ 790 1胃癌细胞在端粒酶活性受抑制后对常用化疗药物顺铂敏感性的变化 ,探索胃癌联合化疗的新途径。一、材料与方法1 细胞培养 :人胃癌细胞系ＳＧＣ 790 1和反义人端粒酶ＲＮＡ转染的ＳＧＣ 790 1细胞 (790 1 ａｈＴＲ) [3] 均培养于含 10 %灭活的小牛血清、10 0 μｇ/ｍｌ链霉素、10…     

顺铂,5-FU联合香菇多糖心包腔灌注治疗恶性心包积液的疗效评价

目的观察顺铂、5-FU联合香菇多糖心包腔灌注治疗恶性心包积液的毒副反应和疗效。方法恶性心包积液患者40例,用一次性中心静脉导管行心包腔置管闭式引流心包腔积液,引流后腔内每次注入DDP 60 mg、5-FU 1000 mg、香菇多糖6mg治疗。结果 CR 33例(82.5%);PR 4例(10%);NC 3例(7.5%),总有效率92.5%。副作用主要是胸痛,恶心和呕吐。结论顺铂、5-FU联合香菇多糖治疗恶性心包积液的疗效显著,可明显改善患者的生活质量,毒副反应轻微,可耐受。     

低浓度顺铂诱导胃癌原代细胞耐药的研究

近年来，5-FU与顺铂（DDP）已成为治疗消化道肿瘤的基本用药。肿瘤对药物的原发性耐药及获得性耐药已成为导致化学治疗失败的主要原因。DDP呈浓度依赖性细胞毒作用，但因毒性大且有体内蓄积现象，故应用剂量受到限制。有研究提出采用小剂量分次用药方式。但有学者认为该种给药方式可能疗效不佳又易诱发耐药，存在较多争议。     

顺铂、香菇多糖联合治疗恶性心包积液疗效观察

2003年9月～2006年2月，我科采用经皮心包腔置管引流术并交替注射顺铂、香菇多糖治疗恶性心包积液患者17例，临床疗效较好。现报告如下。     

阿司匹林对胃癌细胞株7901增殖和凋亡的影响

目的 体外观察阿司匹林（ASA）对胃癌细胞株SGC-7901细胞平殖的影响,并探讨其可能的作用机制。方法 采用噻唑蓝（MTT）法、流式细胞仪（FCM）、电镜和^3h-TdR核素标记等技术,研究ASA和SGC-7901细胞增殖的抑制和可能的机制。结果 MTT显示体外ASA对SGC-7901有细胞毒作用,与浓度和作用时间有相关性,^3H-TdR实验表明,ASA对细胞DNA合成有抑制制作。FCM显示,DNA直方图上出现典型的亚二倍体“凋亡峰”,凋亡率在7.8%-34.4%。使S期、G2/M期细胞比例升高,G1期比例下降,呈一定剂量效应关系。电镜下见典型的细胞凋亡形态学特征：细胞核染色质致密浓缩,凋亡小体形成等。结论 体外ASA对SGC-7901细胞增殖有抑制作用,可能与诱导细胞凋亡和阻止细胞周期的进展有关。     

高温对SGC7901/ADM细胞多药耐药蛋白表达的影响和意义

目的:研究高温43℃对多药耐药基因表达产物P-gp、MRP、LRP在蛋白水平上的影响及其生物学意义,更深入地了解热效应逆转耐药的机制.方法:采用免疫细胞化学染色法、RT-PCR以及Western blot方法,检测在不同温度和不同药物作用下,人胃癌耐药细胞株SGC7901/ADM和对照的人胃癌敏感细胞SGC7901株中,与人胃癌多药耐药相关的分子MDR1、P-gp、MRP、LRP在蛋白水平上的表达差异.结果:采用免疫细胞化学染色法检测人胃癌耐药株SGC7901/ADM细胞,发现高温43℃60 min处理可使P-gp蛋白表达下调率(down-regulated rate,DRR)31.78%(P=0.016),而MRP表达DRR为20.22%(P=0.037),差异有统计学意义,LRP未表达.采用Western blot法在SGC7901细胞中未检测出P-gp蛋白表达,而SGC7901/ADM细胞中P-gp高表达;在ADM和CDDP处理组细胞中,高温43℃时P-gp的表达量较37℃时DRR分别为45.65%(P=0.007)、17.95%(P=0.021),差异有显著学意义;TAX处理组DRR为11.90%,差异无显著学意义(P=0.065).结论:高温43℃的短期处理对人胃癌SGC7901/ADM细胞中P-gp和MRP多药耐药蛋白的表达有一定的抑制作用,可能是逆转耐药的机制之一.     

Bax基因对人胃癌耐药细胞多药耐药性的逆转作用

目的 研究凋亡相关基因Ｂax对胃癌多药耐药细胞的多药耐药性的逆转作用。方法 构建含有人Ｂax cＤＮＡ全长的真核表达载体pＢＫ－Ｂax,经脂质体导入缺乏Ｂax蛋白表达的人 胃癌多药耐药细胞系ＳＧＣ７９０１/ＶＣＲ中。Ｗestern印迹观察Ｂax基因在转导细胞中的表达,ＭＴＴ法检测Ｂax转导细胞与空载体转导细胞对化疗药物的敏感性。结果 成功构建了Ｂax的真核表达载体,Ｂav转导细胞能稳定表达Ｂax蛋白,与空载体转导细胞相比。Ｂ     

人端粒保护蛋白反义核酸抑制SGC7901胃癌细胞增殖

目的 研究人端粒保护蛋白（human protection of telomeres,hPOT1）对胃癌细胞生长增殖的作用.方法 利用本课题组先前所构建的hPOT1正、反义核酸真核表达载体,转染SGC7901胃癌细胞,G418筛选阳性克隆,用Western印迹法、MTT法、流式细胞仪、透射电镜等技术观察基因转染后SGC7901细胞hPOT1蛋白的表达、细胞生长曲线、细胞周期、细胞凋亡及细胞形态学的变化.结果 转染了hPOT1反义核酸真核表达载体（pcDNA-as-hPOT1）的SGC7901胃癌细胞hPOT1表达降低,生长减慢,阻滞于G2/M期,细胞凋亡增加.结论hPOT1反义核酸真核表达载体能显著抑制hPOT1蛋白的表达,hPOT1蛋白可能参与胃癌细胞的周期调控,并与细胞的生长增殖有关.     

Reversal of multidrug resistance in vincristine-resistant human gastric cancer cell line SGC7901/VCR by LY980503

AIM： To investigate the reversal effect of LY980503, a benflumetol derivative, on multidrug resistance in vincristine （VCR） -resistant human gastric carcinoma cell line SGC7901/VCR.
METHODS： Cells of a human gastric cancer cell line, SGC7901, and its VCR-resistant variant, SGC7901/VCR, were cultivated with LY980503 and/or doxorubicin （DOX）. The cytotoxicity of drugs in vitro was assayed by M-IF method. Based on the flow cytometric technology, the uptake of DOX was detected in these cells by measuring DOX -associated mean fluorescence intensity （MFI）.
RESULTS： SGC7901/VCR cells were 23.5 times more resistant to DOX in comparison with 5GC7901 cells. LY980503 at the concentrations of 2.0 μmol/L -10 μmol/ L had no obvious cytotoxicity to SGC7901 and SGC7901/ VCR cells. After simultaneous treatment with LY980503 at the concentrations of 2.0, 4.0 and 10 μmol/L, the ICso of DOX to SGC7901/VCR cells decreased from 1.6 ± 0.12 μmol/L to 0.55 ± 0.024, 0.25 ± 0.032 and 0.11 ± 0.015 μmol/L, respectively, thus, increasing the DOX sensitivity by 2.9-fold （P 〈 0. 05）, 6.4-fold （P 〈 0. 01） and 14.5-fold （P 〈 0. 01）, respectively. In the uptake study of DOX, simultaneous incubation of SGC7901/VCR cells with LY980503 significantly increased the DOX -associated MFI in SGC7901/VCR cells. No such results were found in parental SGC7901 cells.
CONCLUSION： LY980503 at non-cytotoxic concentrations can effectively circumvent resistance of SGC7901/VCR cells to DOX by increasing intracellular DOX accumulation.     

Localization and translocation of RhoA protein in the human gastric cancer cell line SGC-7901

AIM： To elucidate the localization of RhoA in gastric SGC-7901 cancer cells and its translocation by lysophosphatidic acid （LPA） and/or 8-chlorophenylthio- cAMP （CPT-cAMP）.
METHODS： Immunofluorescence microscopy was used to determine the localization of RhoA. Western blotting was used to detect both endogenous and exogenous RhoA in different cellular compartments （membrane, cytosol, nucleus） and the translocation of RhoA following treatment with LPA, CPT-cAMP, or CPT-cAMP ＋ LPA.
RESULTS： Immunofluorescence staining revealed endogenous RhoA to be localized in the membrane, the cytosol, and the nucleus, and its precise localization within the nucleus to be the nucleolus. Western blotting identified both endogenous and exogenous RhoA within different cellular compartments （membrane, oltosol, nucleus, nucleolus）. After stimulation with LPA, the amount of RhoA within membrane and nuclear extracts increased, while it decreased in the cytosol fractions. After treatment with CPT-cAMP the amount of RhoA within the membrane and the nuclear extracts decreased, while it increased within the cytosol fraction. Treatment with a combination of both substances led to a decrease in RhoA in the membrane and the nucleus but to an increase in the cytosol.
CONCLUSION： In SGC-7901 cells RhoA was found to be localized within the membrane, the cytosol, and the nucleus. Within the nucleus its precise localization could be demonstrated to be the nucleolus. Stimulation with LPA caused a translocation of RhoA from the cytosol towards the membrane and the nucleus; treatment with CPT-cAMP caused the opposite effect. Furthermore, pre-treatment with CPT-cAMP was found to block the effect of LPA.     

Heat shock protein 70 antisense oligonucleotide inhibits cell growth and induces apoptosis in human gastric cancer cell line SGC-7901

AIM: Heat shock protein (HSP)70 is over-expressed in human gastric cancer and plays an important role in the progression of this cancer. We investigated the effects of antisense HSP70 oligomer on human gastric cancer cell line SGC-7901, and its potential role in gene therapy for this cancer. METHODS: Human gastric cancer cell line SGC-7901 was treated in vitro with various concentrations of antisense HSP70 oligonucleotides at different intervals. Growth inhibition was determined as percentage by trypan blue dye exclusion test. Extracted DNA was electrophoresed on agarose gel, and distribution of cell cycle and kinetics of apoptosis induction were analyzed by propidium iodide DNA incorporation using flow cytometry, which was also used to detect the effects of antisense oligomer pretreatment on the subsequent apoptosis induced by heat shock in SGC-7901 cells. Proteins were extracted for simultaneous measurement of HSP70 expression level by SDS-PAGE Western blotting. RESULTS: The number of viable cells decreased in a dose-and time-dependent manner, and ladder-like patterns of DNA fragments were observed in SGC-7901 cells treated with antisense HSP70 oligomers at a concentration of 10μmol/L for 48 h or 8μmol/L for 72 h, which were consistent with inter-nucleosomal DNA fragmentation. Flow cytometric analysis showed a dose- and time-dependent increase in apoptotic rate by HSP70 antisense oligomers. This response was accompanied with a decrease in the percentage of cells in the G_1 and S phases of the cell cycle, suggesting inhibition of cell proliferation. In addition, flow cytometry also showed that pretreatment of SGC-7901 cells with HSP70 antisense oligomers enhanced the subsequent apoptosis induced by heat shock treatment. Western blotting demonstrated that HSP70 antisense oligomers inhibited HSP70 expression, which preceded apoptosis, and HSP70 was undetectable at the concentration of 10 μmol/L for 48 h or 8 μmol/L for 72 h. CONCLUSION: Antisense HSP70 oligomers can abrogate HSP70 expression in SGC-7901 cells, which may in turn induce apoptosis and inhibit cell proliferation, conversely suggesting that HSP70 is required for the proliferation and survival of human gastric cancer cells under normal conditions.