孕激素对乳腺癌细胞中雌激素代谢酶的影响

目的:选取5种常用于激素替代治疗(HRT)的孕激素,体外检测其不同类型、不同浓度、不同用药方式对乳腺癌细胞中雌激素代谢酶的影响。方法:培养人乳腺癌细胞T47D,MCF-7和MCF-7/aro,经E2和不同类型、不同浓度孕激素(P)作用后,Northern Blotting或RT-PCR技术检测雌激素代谢酶的mRNA表达,同位素标记的底物用于酶的活性测定。进一步模拟活体HRT,建立序贯治疗(SCR)和连续联合用药(CCR)的体外细胞模型。结果:与单用E2组相比,安宫黄体酮(MPA,10-8M-10-6M)与E2(10-8M)共同作用后,可上调雌激素活化酶芳香化酶、17β羟基甾醇脱氢酶Ⅰ型(17β-HSD1)、硫酸酯酶(STS)的活性并使mRNA表达升高。黄体酮(P4)也有上述作用,但是影响较小。左炔诺孕酮(LNG)、炔诺酮(NET)和地诺孕酮(DNG)对酶没有刺激作用。未见孕激素对雌激素抑制酶17β羟基甾醇脱氢酶Ⅱ型(17β-HSD2)和硫酸酯转移酶具有刺激作用。CCR体外细胞模型中检测到芳香化酶和17β-HSD1活性增加,而SCR模型中没有明显的酶刺激反应。结论:孕激素不同类型、不同用药方式对乳腺癌细胞中的雌激素代谢酶产生不同的作用,与其他孕激素相比,MPA对酶的刺激作用最强,其用于HRT是否通过上调酶的活性增加乳腺癌发病风险,尚有待研究。     

17β-雌二醇对乳腺癌细胞的增殖作用及其对雌激素受体相关受体的调控作用

目的 研究17β-雌二醇(17β-E2)对乳腺癌细胞MCF-7增殖作用及其对雌激素受体相关受体(ERRα)的调控作用.方法 分别用10-12、10-11、10-10、10-9、10-8、10-7、10-6mol/L的17β-E2作用于MCF-7细胞24h,以DMSO作为溶剂对照,采用MTr法测定细胞增殖情况.分别用10-10、10-9、10-8、10-7mol/L 17β-E2作用于MCF-7细胞24 h后,采用RT-PCR法检测ERRa表达水平的变化.结果 10-12、10-11、10-10、10-9、10-8、10-7mol/L剂量17β-E2作用于MCF-7细胞24h后,对细胞的增殖率分别为112.09%,122.09%,123.42%,120.46%,124.60%,109.23%,均能促进细胞生长,并且随着受试物浓度的增加,细胞增殖效应增加,在10-6mol/L剂量时达到最大,而10-6 mol/L剂量的17β-E2作用于MCF-7细胞24 h后,其增殖率为67.97%,对细胞生长的产生抑制.10-10、10-9、10-8、10-7 mol/L 17β-E2作用于MCF-7细胞24 h后,ERRa的表达水平上调.结论 一定剂量范围内17β-雌二醇对MCF-7细胞有增殖作用,并且可以上调ERRα表达,提示ERRα在调节乳腺癌细胞生长中可能发挥着重要作用.     

开环异落叶松树脂酚对乳腺癌MCF-7细胞增殖的影响

目的研究开环异落叶松树脂酚(SECO)及其代谢产物肠内酯(ENL)、肠二醇(END)对人乳腺癌MCF-7细胞株增殖的影响,揭示其可能的作用机制。方法采用四甲基偶氮唑盐(MTT)比色法测定SECO、END与ENL对MCF-7细胞增殖的影响,并与染料木黄酮(GEN)进行对比。采用光学显微镜与流式细胞仪(FCM)检测了MCF-7细胞生长过程中受到的影响,分析了SECO抗乳腺癌的作用机制。结果低浓度SECO对MCF-7细胞增殖起促进作用,高浓度SECO对MCF-7细胞增殖起明显的抑制作用;呈现G2/M期阻滞。光学显微镜观察到细胞凋亡的形态。ENL与END则在不同浓度下均表现出抑制作用。结论SECO对MCF-7细胞的增殖具有浓度依赖效应,其抑制MCF-7细胞增殖作用可能与其代谢产物有关。     

环境雌激素辛基酚对人MCF-7细胞凋亡调控基因bcl-2mRNA表达的影响

目的 研究具有雌激素活性的环境污染辛基酚对雌激素受体阳性的乳腺癌细胞MCF-7凋亡调控基因bcl-2mRNA表达的影响及与对雌二醇作用的异同。方法 分别以不同浓度的17β-雌二醇和辛基酚刺激体外培养的MCF-7细胞12～120h，用RT-PCR方法测定细胞bcl-2mRNA的表达量。结果 17β-雌二醇和辛基酚作用MCF-7细胞24h后bcl-2mRNA表达量显著升高，持续至120h,较宽浓度范围的辛基酚均可引起bcl-2表达增高向，以10^-6mol/L作用最强。结论 辛基酚具有类似雌二醇的刺激PCF-7细胞bcl-2表达的作用，但作用强度不如雌二醇。     

狼毒大戟总提取物对乳腺癌细胞增殖及周期的影响

目的:观察狼毒总提取物对乳腺癌细胞增殖及周期影响。方法:CCK-8法测定该药对MCF-7、MDAMB-231、SK-Br-3细胞株增殖影响,流式细胞术检测狼毒总提取物对MCF-7细胞周期影响。结果:狼毒总提取物对细胞IC50浓度分别为227ug/ml、793ug/ml、1034ug/ml。药物作用随着药物浓度提高。MCF-7周期检测,G0/G1期期比例下降、S期比例上升。结论:狼毒提取物对MCF-7、MDA-MB-231、SK-Br-3细胞生长均有抑制作用。主要研究了MCF-7细胞抑制机制,提示狼毒大戟总提取物抑制MCF-7细胞G_2/M期到G_0/G_1其转换。     

二氯二苯二氯乙烯的类雌激素活性的实验研究

目的研究二氯二苯二氯乙烯(DDE)的类雌激素活性对人乳腺癌细胞株MCF-7增殖的影响。方法采用了体外MCF-7细胞增殖试验检测了DDE(3×10-5、3×10-6、3×10-7、3×10-8、3×10-9 mol/L)的类雌激素活性,并用生长曲线分析对其作用机制进行了初步探讨。结果3×10-6 mol/LDDE染毒组吸光度值高于溶剂对照组且MST-7细胞增殖的生长曲线与10-9 mol/L17β-雌二醇染毒组相似。结论DDE具有刺激MCF-7细胞增殖的类雌激素活性,其机制可能与17β-雌二醇相同。     

P,P’-DDD对人乳腺癌细胞的增殖作用

[目的]观察对,对-二氯二苯基二氯乙烷（P,P’-DDD）对人乳腺癌（MCF-7）细胞增殖的影响。[方法]采用体外培养MCF-7细胞增殖试验检测DDD的类雌激素活性,并用生长曲线对其作用机制进行初步探讨。[结果]DDD染毒剂量在3×10^-7mol／L、3×10^-6mol／L时,存在刺激MCF-7细胞增殖的类雌激素活性（P〈0．05）,在3×10^-6mol／L剂量时其增殖效应最大。细胞生长曲线方面,DDD组在第3、5、7天各时间段细胞数均明显高于溶剂对照组（P〈0．05）。[结论]DDD在3×10^-7mol／L、3×10^-6mol／L具有刺激MCF．7细胞增殖的类雌激素活性。     

洛伐他汀对转染乳腺癌细胞增殖功能的影响

目的探讨胆固醇合成抑制洛伐他汀(Lovastatin，LOV)对人乳腺癌易感基因1(Breast cancer1，BRCA1)转染的密西根癌症基金会-7乳腺癌细胞(Michigan Cancer Foundation-7 breast cancer cell，MCF-7)增殖功能的影响。方法应用基因转染技术获得BRCA1高表达的MCF-7乳腺癌细胞(MCF-7^BRCA1)，经8μmol／L LOV处理未转染组(MCF-7)与转染组(MCF-7^BRCA1)细胞1～3d后，通过生长曲线、二甲基偶氮唑蓝(MTT)染色和透射电镜等方法．观察LOV对MCF-7及MCF-7^BRCA1乳腺癌细胞增殖功能的影响。结果LOV处理乳腺癌细胞均能抑制未转染组和转染组细胞的增殖，以MCF-7^BRCA1细胞的变化更为显著。透射电镜结果显示，LOV能明显诱导MCF-7^BRCA1转染组细胞向正常细胞的分化。结论乳腺癌细胞BRCA1基因的高表达可增强LOV对细胞的增殖抑制作用．     

氯化汞雌激素样作用及其机制的实验研究

目的评价氯化汞(HgCl2)的雌激素样作用及其作用机制.方法从体内和体外两个水平,观察不同浓度的HgCl2对MCF-7人乳腺癌细胞增殖作用、去卵巢SD大鼠子宫的诱导增生作用、过氧化物活力的变化及对雌激素结合雌激素受体的影响.结果 10-6～10-9 mol/L的HgCl2均可引起MCF-7人乳腺癌细胞增殖,10-7 mol/L的HgCl2使MCF-7人乳腺癌细胞增殖达最大.每天0.04、0.20及1.00 mg/kg连续3 d腹腔注射HgCl2能刺激大鼠子宫增生和过氧化物酶活力增加;但HgCl2不影响雌二醇(E2)与雌激素受体结合.结论 HgCl2可能通过雌激素受体介导而表现出雌激素样作用,但不与E2竞争结合雌激素受体.     

枸橼酸芬太尼对乳腺癌细胞体外增殖和侵袭的影响

目的:探讨枸橼酸芬太尼对人乳腺癌MCF-7细胞体外增殖和侵袭的影响。方法:分别用0.000 1μmol/L、0.01μmol/L、1μmol/L的枸橼酸芬太尼处理MCF-7细胞,MTT比色法检测MCF-7细胞增殖;流式细胞仪检测MCF-7细胞细胞周期;采用划痕实验及侵袭小室法检测MCF-7细胞侵袭能力。结果:MTT比色法显示不同浓度枸橼酸芬太尼处理的MCF-7细胞的增殖率分别为(58.84±11.31)%、(54.37±9.89)%和(51.83±10.33)%,明显低于对照组;各组MCF-7细胞停滞在G2/M期的比例增加,S期比例减少;各实验组及对照组划痕实验显示48 h时间段的愈合率分别为(70.41±6.86)%、(64.36±3.87)%、(62.52±4.95)%和(83.34±4.59)%;侵袭小室实验显示枸橼酸芬太尼在体外具有抑制MCF-7细胞侵袭转移作用。结论:芬太尼可抑制人乳腺癌MCF-7细胞的增殖、使细胞周期停滞于G2/M期,并且降低其侵袭能力,对MCF-7细胞的生物学性状产生较大的影响。     

Anti-apoptotic action of zearalenone in MCF-7 cells

Zearalenone (ZEA), a nonsteroidal estrogenic mycotoxin, is present in high concentrations in dairy products and cereals. Studies have indicated that ZEA could strongly provoke proliferation in estrogen-dependent breast cancer MCF-7 cells following estrogen ablation. The current study confirmed the previous studies that within the range of concentrations of 2-96nM, like endogenous estradiol, ZEA could stimulate proliferation in MCF-7 cells with inducing a profound increase in S phase and a modest increase in G(2)/M phase that was accompanied by a decrease in G(0)/G(1) phase. The Cell Death Detection ELISA was used to determine whether the robust cell viability retrieved by ZEA was a result of inhibited apoptosis. Data indicated that ZEA-mediated inhibition of apoptosis is significantly evident (P<0.05) and in a dose-dependent manner. Western blot and multiple RT-PCR analysis revealed that the anti-apoptotic bcl-2 was upregulated at both protein and mRNA levels, together with the downregulation of pro-apoptotic bax. In short, the results here showed that ZEA possessed comparative estrogenic activity and could promote the progression of MCF-7 cells through the cell cycle by a decrease in G(0)/G(1) phase and a significant increase in S phase. The pro-proliferative activity of ZEA was due to inhibition of apoptosis through regulation of bax/bcl-2 expression. Therefore, we conclude that contamination of ZEA in food might contribute to the increasing incidence rates of breast cancer.     

植物雌激素对乳腺癌细胞MCF-7增殖的影响

目的 :　探讨植物雌激素大豆异黄酮 (genistein,GS)和玉米赤霉烯酮 (zearalenone,ZEA)对乳腺癌细胞株 MCF- 7增殖的影响。方法 :　雌激素依赖性 MCF- 7细胞在 DMEM培养液(含小牛血清 1 0 % )中采用开放式单层贴壁培养 ,于加受试物前 5 d将细胞用 PBS洗涤后改为无酚红高糖 DMEM(含 5 %经活性碳 -葡聚糖苷处理的胎牛血清 ,CDT- FBS)培养 ,实验设溶剂对照、雌激素对照、抗雌激素对照及两种受试物各四个剂量组 ,采用噻唑蓝 (MTT)法、3H- Td R掺入法及流式细胞术对 MCF- 7细胞的增殖情况进行分析。结果 :　与溶剂对照组相比较 ,GS(96μmol/ L,2 4h)可明显抑制 MCF- 7细胞增殖和细胞 DNA合成 ,并将细胞周期阻滞在 G2 / M;8μmol/ L GS处理96 h也能产生类似的抑制效果。 96 nmol/ L ZEA处理 2 4 h可明显促进 MCF- 7细胞增殖和细胞DNA合成 ,并将细胞周期由 G0 / G1向 S期推进 ,提高细胞分裂增殖指数。结论 :　ZEA和 GS均属环境雌激素 ,但对乳腺癌细胞 MCF- 7增殖产生的影响不同 ,ZEA可促进 MCF- 7增殖 ,而 GS能够抑制 MCF- 7细胞的增殖 ,即 GS具有用于癌症预防及有关保健食品开发的价值     

玉米赤霉烯酮对乳腺癌细胞MCF-7增殖和凋亡的影响

目的 观察真菌雌激素玉米赤霉烯酮（ZEA）对人乳腺癌细胞MCF-7增殖和凋亡的影响,并初步探讨其分子生物学作用机制。方法 用噻唑蓝比色法观察ZEA对MCF-7细胞增殖活力流式细胞术观察ZEA对MCF-7细胞增殖活力和细胞周期分布的影响;用凋亡DNA片段检测试剂盒和流式细胞术从不同方面检测ZEA对细胞凋亡的影响;逆转录聚合酶链反应（RT-PCR）和蛋白印迹技术检测ZEA对bcl-2和bax mRNA和蛋白质表达的影响。结果 MCF-7细胞生长为雌激素依赖性：溶剂对照组（外源性雌激素缺乏且内源性雌激素耗尽的条件下）细胞增殖活力为100％,10nmol／L雌二醇组细胞增殖活力为257．6％;另外,以溶剂对照组发生凋亡率为100％来计,10nmol／L雌二醇组细胞凋亡率只有为10．8％。ZEA对MCF-7细胞生物学效应的影响同雌二醇类似：在2～96nmol／L浓度范围内,ZEA可快速恢复MCF-7细胞增殖活力（96nmol／L组细胞增殖活力为对照组的2．4倍）,提高S期细胞分布比例（96nmol／L组S期细胞分布比例为对照组的2．3倍）,降低凋亡百分率（96nmol／L组细胞细胞凋亡率为对照组的23．7％）,并呈现出良好的剂量-效应关系。RT-PCR和蛋白印迹结果分析显示,ZEA能够促进bcl-2 mRNA和蛋白质表达,对bax的表达则表现出抑制作用。结论 同雌激素类似,ZEA可提高MCF-7细胞增殖活力并促进有丝分裂指数;通过对bcl-2和bax表达的调节作用,ZEA可抑制雌激素耗尽所诱导的MCF-7细胞凋亡。     

Effects of Xenoestrogenic Environmental Pollutants on the Proliferation of a Human Breast Cancer Cell Line (MCF-7)

A human breast cancer cell line (MCF-7) was used to develop an in vitro screening assay for the detection of xenoestrogenic environmental pollutants. MCF-7 cells were cultured in DMEM containing 5% fetal bovine serum (FBS). An estrogenic response was defined as an increase in the frequency of proliferating MCF-7 cells, and was measured using a thymidine analog, bromodeoxyuridine, and flow cytometry. Di-2-ethylhexyl phthalate (DEHP) and 4-n-nonylphenol (4-n-NP) were used as model chemicals. The proliferation rate of S-phase cells after 24 h of exposure to various concentrations of 17β-estradiol and to model compounds was compared with a positive and a negative control, containing 1 nM 17β-estradiol and 0.1% ethanol, respectively. DEHP and 4-n-NP increased the frequency of proliferating MCF-7 cells in a dose-dependent manner. The lowest concentration that significantly increased the proliferation of MCF-7 cells was 10 μM for DEHP and 1 μM for 4-n-NP. The results showed that the assay is accurate and quick to perform. It may prove a valuable tool for screening potential estrogen-mimicking environmental pollutants. Received: 5 May 1997/Accepted: 9 September 1997     

Bleeding patterns of women using Lunelle monthly contraceptive injections (medroxyprogesterone acetate and estradiol cypionate injectable suspension) compared with those of women using Ortho-Novum 7/7/7 (norethindrone/ethinyl estradiol triphasic) or other oral contraceptives

Persistent and/or unpredictable bleeding is a common reason for discontinuation of hormonal contraceptive methods. An open-label, nonrandomized, parallel, controlled study compared the efficacy, safety, and cycle control of the new, highly efficacious monthly injectable contraceptive containing 25 mg medroxyprogesterone acetate (MPA) and 5 mg estradiol cypionate (E₂C) (MPA/E₂C) (Lunelle™ Monthly Contraceptive Injection) with that of the frequently used norethindrone 0.5, 0.75, 1.0 mg/0.035 mg ethinyl estradiol (NET/EE) triphasic oral contraceptive (Ortho-Novum^® 7/7/7). This report directly compares the bleeding patterns of women on MPA/E₂C to those of women on NET/EE and untreated women. Overall, breakthrough bleeding occurred less frequently in women using MPA/E₂C than in women using NET/EE (p ≤0.01). However, more women using MPA/E₂C experienced amenorrhea/missed periods than those on NET/EE (p ≤0.01). In addition, the percentage of women experiencing breakthrough bleeding or amenorrhea while using other oral contraceptives is compared to that of women using MPA/E₂C. A rapidly reversible method, MPA/E₂C, combines the high contraceptive efficacy of surgical sterilization with the convenience of monthly administration. These data suggest that, for a large proportion of women, MPA/E₂C offers predictability in bleeding patterns comparable to or greater than that experienced by ovulatory untreated women or those using combination oral contraceptives.     

Comparative effects of Lunelle monthly contraceptive injection (medroxyprogesterone acetate and estradiol cypionate injectable suspension) and ortho-Novum 7/7/7 oral contraceptive (norethindrone/ethinyl estradiol triphasic) on lipid profiles. Investigators from the Lunelle Study Group

As part of a 60-week, open-label, nonrandomized, parallel, controlled study comparing a monthly contraceptive injection containing medroxyprogesterone acetate (MPA) 25 mg and estradiol cypionate (E(2)C) 5 mg (Lunelle Monthly Contraceptive Injection) and a norethindrone 0.5, 0.75, 1.0 mg/0.035 mg ethinyl estradiol (NET/EE) triphasic oral contraceptive (Ortho-Novum(R) 7/7/7), a longitudinal examination of lipid profiles was conducted. Lipid parameters were assessed at screening and at weeks 20, 40, and 60 (or the final visit) in 114 women using MPA/E(2)C and 93 using NET/EE (lipid analysis population). Extra blood samples were obtained at weeks 21, 22, and 23 in 61 MPA/E(2)C users and 51 NET/EE users (index-cycle analysis population) to investigate lipid changes during one cycle of use.In the index-cycle population, median changes from screening to week 60 showed a decrease in apolipoprotein (apo) A-I and apo A-II in both groups. MPA/E(2)C users had a decrease in total cholesterol (C), total triglycerides, low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C), with maintenance of the total C/HDL-C ratio. NET/EE users showed an increase in total C and LDL-C, with no change in HDL-C or the total C/HDL-C ratio. Within the index cycle (weeks 20 to 23), median changes in lipid values in both MPA/E(2)C and NET/EE users were generally greatest during the first week after the injection or the start of the pill pack.The results of this first longitudinal examination of serum lipids in US women using MPA/E(2)C confirm earlier findings in women in other countries. However, a direct comparison of the effects of MPA/E(2)C and NET/EE on lipid profiles was not possible in this study because of its design and because of the baseline and pharmacokinetic/pharmacodynamic differences between the two contraceptive groups. The results of this analysis showed that, although overall lipid values decreased, including a significant decrease in HDL cholesterol, the maintenance of the total-C/HDL-C ratio suggests that the effect of MPA/E(2)C on lipid parameters may not negatively affect CVD risk over 1 year of use. However, these results warrant further investigation, given the nature of this trial.     

Comparative safety, efficacy, and cycle control of Lunelle monthly contraceptive injection (medroxyprogesterone acetate and estradiol cypionate injectable suspension) and Ortho-Novum 7/7/7 oral contraceptive (norethindrone/ethinyl estradiol triphasic). Lunelle Study Group

An open-label, nonrandomized, parallel, controlled study compared the efficacy, safety, and cycle control of a new monthly injectable contraceptive containing 25 mg of medroxyprogesterone acetate (MPA) and 5 mg of estradiol cypionate (E2C) (MPA/E2C) (Lunelle Monthly Contraceptive Injection) with that of a norethindrone 0.5, 0.75, 1.0 mg/0.035 mg ethinyl estradiol (NET/EE) triphasic oral contraceptive (Ortho-Novum 7/7/7). At study enrollment, women chose either the injections or the oral contraceptive. A higher proportion of women in the NET/EE group (65.1%) than in the MPA/E2C group (48.7%) had used hormonal contraception during the month before the study (p < 0.01). Overall, 55.5% (434/782) of MPA/E2C users and 67.6% (217/321) of NET/EE users completed the 60-week trial. One-year contraceptive efficacy (13 cycles of 28 days) for MPA/E2C and NET/EE was based on 8008 and 3434 woman-cycles of use, respectively. During the first year, one pregnancy occurred in an NET/EE user for a life table rate of 0.3; no pregnancies occurred in users of MPA/E2C. One additional pregnancy in the NET/EE group occurred during the 15th treatment cycle. After the first treatment cycle, women in both groups experienced regular menses, with an average cycle length of 28 days in MPA/E2C users and 27 days in NET/EE users. Although MPA/E2C users were more likely to experience bleeding irregularities, only 2.5% (19/775) cited metrorrhagia as a reason for discontinuing treatment. The adverse events reported in both treatment groups are consistent with those expected with the use of combined hormonal contraceptives. Overall, the results of this first Phase III US clinical trial of MPA/E2C confirm this method's high contraceptive efficacy and safety, as shown in previous studies by the World Health Organization. These results suggest that a monthly combination injectable would represent a welcome new contraceptive option for women in the US.     

三种增塑剂对乳腺癌细胞株MCF-7增殖的影响

目的　观察对 壬基酚 (NP)、双酚A(BisA)和邻苯二甲酸酯二丁酯 (DBP)对乳腺癌细胞株MCF 7增殖的影响。方法　将MCF 7细胞在达尔克 (DMEM)培养液 (含 10 %小牛血清 )中采用开放式单层贴壁培养 ,开始实验前将培养细胞用磷酸盐缓冲液 (PBS)洗涤后改在无酚红DMEM (含 5 %胎牛血清 )中培养继续 4d以耗尽其内源性雌激素。实验设溶剂对照、雌激素对照、抗雌激素对照及 3种受试物各 4个剂量组 ,采用噻唑蓝 (MTT)法、3 H TdR掺入法及流式细胞术对MCF 7细胞的增殖情况进行分析。结果　与对照组相比 ,NP、BisA和DBP对细胞处理 2 4h ,分别在 96× 10 -7mol/L、96× 10 -7mol/L、96× 10 -6mol/L可促进MCF 7细胞增殖和细胞DNA合成 ,并推进G0 /G1期细胞进入S期 ,提高细胞增殖指数 ;随着培养时间延长至 96h ,3种化合物在较低浓度条件下也表现促进细胞增殖的效果。结论　对 壬基酚、双酚A和邻苯二甲酸酯二丁酯可促进雌激素依赖性乳腺癌细胞MCF 7的增殖 ,可能具有雌激素样作用。