FFJ-5下调PKM2抑制MCF7生长及逆转MCF7/DOX细胞耐药性的研究

目的探讨FFJ-5对人乳腺癌细胞MCF7及其耐药细胞MCF7/DOX的作用及其机制。方法采用MTT法检测FFJ-5对MCF7及MCF7/DOX细胞的增殖抑制作用及其对柔红霉素(doxorubicin,DOX)在耐药细胞MCF7/DOX中化疗敏感性的影响;Western blot检测FFJ-5对EGFR、p-EGFR、Akt、p-Akt、PKM2、caspase-3、cleaved caspase-3、PARP、cleaved PARP及P-gp蛋白表达的影响;DNA ladder分析检测FFJ-5对细胞基因组DNA的影响;RT-PCR检测低剂量FFJ-5对多药耐药基因MDR1 mRNA水平的影响。结果 FFJ-5抑制了MCF7细胞生长,降低了MCF7细胞中EGFR、Akt的表达及活性,下调了PKM2水平;FFJ-5可激活caspase-3、促使基因组DNA断裂;同时FFJ-5也能抑制耐药细胞MCF7/DOX生长,并增强DOX在MCF7/DOX细胞中的活性,同时降低了MCF7/DOX细胞中EGFR、p-EGFR及PKM2水平,但对MDR1 mRNA水平无影响。结论 FFJ-5可通过抑制EGFRAkt-PKM2通路及激活线粒体凋亡相关因子caspase-3来抑制MCF7细胞生长,并诱导其凋亡,并可逆转MCF7/DOX的耐药性。     

椎茸的乙酸乙脂提取物诱导人乳腺癌MCF-7细胞凋亡的作用

目的观察椎茸的乙酸乙脂提取物对体外培养的人乳腺癌MCF7细胞株诱导凋亡的作用。方法MTT法测定提取物对MCF7细胞生长的影响;AnnexinVFITC和PI染色,采用FCM测定MCF7细胞的凋亡指数;采用FCM分析细胞周期的影响;Westernblot法分析CyclinD1、Cdk4、Bax和p21WAE1/CIP1表达。结果椎茸的乙酸乙脂提取物可以剂量依赖性的抑制乳腺癌细胞株MCF7的生长,使MCF7细胞生长停滞在G0/G1期而诱导MCF7细胞凋亡;通过Bax和p21WAE1/CIP1的表达和降低CyclinD1、Cdk4的表达而诱导MCF7细胞的凋亡。结论椎茸的乙酸乙脂提取物通过诱导细胞凋亡而产生抗乳腺癌的活性。     

隐丹参酮对乳腺癌他莫昔芬耐药细胞的生长抑制作用与机制研究

本研究探讨了隐丹参酮(cryptotanshinone, CPT)对乳腺癌他莫昔芬耐药细胞MCF7-TAMR的抑制作用及机制。采用MTT法检测CPT对MCF7-TAMR细胞的生长抑制作用,发现CPT剂量与时间依赖性抑制MCF7-TAMR细胞的生长, 24 h半数抑制浓度(IC₅₀)为15.14±2.82μmol·L^-1。CPT可阻滞细胞周期于G0/G1期,并通过上调细胞内活性氧(reactive oxygen species, ROS)水平促进细胞凋亡。Transwell结果显示CPT对MCF7-TAMR细胞的迁移有显著抑制作用。此外, CPT降低了MCF7-TAMR细胞来源微球体中CD24^-/lowCD44⁺细胞群。Western blot结果证明, CPT有效抑制雌激素受体-α (estrogen receptor α, ER-α)磷酸化,抑制磷酸肌醇3-激酶(phosphatidylinositol 3-kinase, PI3K-p85)与丝氨酸-苏氨酸激酶(serine-threonine ...     

杠柳苷元抑制人乳腺癌细胞增殖作用的研究

目的 观察杠柳苷元(periplogenin)对人乳腺癌细胞MCF7的抑制作用并考察其抑制作用的机理.方法 使用四氮唑盐(MTT)法测定杠柳苷元对MCF7细胞的增殖抑制效果,并使用蛋白免疫印迹法测定其中凋亡蛋白的表达.结果 杠柳苷元对MCF7细胞起到了明显的抑制作用,其抑制作用呈剂量依赖性,蛋白免疫印迹法也观察到杠柳苷元促进MCF7细胞内凋亡相关蛋白的表达,其表达呈时间依赖性.结论 杠柳苷元具有显著的体外抑制MCF7细胞增殖的作用,其抑制作用是通过促进MCF7细胞凋亡而发挥的.     

人参皂甙-Rh2对人乳腺癌MCF7/AdrR细胞增殖和凋亡的影响

目的 研究人参皂甙-Rh2(GS-Rh2)对乳腺癌MCF7//AdrR细胞增殖和凋亡的影响.方法 以MCF7/AdrR细胞不加药物干预,作为对照组;以Rh2单独作用于MCF7/AdrR细胞,作为Rh2组;以低浓度阿霉素(ADM)单独作用于MCFT/AdrR细胞,作为ADM组;以Rh2和阿霉素联用于MCF7/AdrR细胞,作为Rh2+ADM组.用MTF比色法观察GS-Rh2对体外培养的MCF7//AdrR细胞生长的抑制作用;用荧光显微镜观察用药前后MCF7/AdrR细胞的形态学变化;用流式细胞仪检测凋亡细胞和细胞周期变化;用Western blot的方法检测Fas、Bax、Bcl-2及Bcl-xL蛋白表达的变化.结果 MCF7/AdrR细胞经GS-Rh2作用后,生长受抑制,呈剂量和时间依赖性;显微镜显示,经GS-Rh2作用后,MCF7/AdrR细胞呈较明显的凋亡形态学改变,GS-Rh2能将细胞周期阻滞于G0/G1期,同时可能参与促凋亡蛋白Fas、Bax表达升高及抑制凋亡蛋白Bcl-2表达降低;但在GS-Rh2处理前后Bcl-xL无明显变化.结论 GS-Rh2能抑制体外培养的MCF7/AdrR细胞增殖并诱导其凋亡,且这种作用可能是通过上调Fas、Bax表达、下调Bcl-2表达以及阻滞细胞周期而实现.     

胡椒碱对乳腺癌阿霉素耐药细胞株 MCF -7/ADM 细胞的逆转作用

目的：探讨胡椒碱对人乳腺癌阿霉素（ADM）耐药细胞株 MCF -7/ ADM 的逆转作用及其机制。方法采用 CCK -8法观察胡椒碱联合阿霉素（ADM）对乳腺癌耐药株 MCF -7/ ADM 细胞生长增殖的影响;应用免疫印迹技术（Western - blot）测定胡椒碱联合 ADM 对MCF -7/ ADM 细胞表面 P -糖蛋白（P - gp）表达的影响。结果60,80,100μmol / L 胡椒碱试验组细胞耐药逆转倍数分别为1.62,2.08,3.78倍,差异有统计学意义（ P ﹤0.05）。胡椒碱能显著抑制 MCF -7/ ADM 细胞膜 P - gp 蛋白的表达,其作用随浓度的增加而增强。结论胡椒碱与 ADM 共同作用于 MCF -7/ ADM 细胞,可使细胞对 ADM 的敏感性增强。胡椒碱具有部分逆转 MCF -7/ ADM 细胞耐药的作用,其逆转作用机制可能与通过下调 P - gp 的表达有关。     

人参皂甙Rh_2抗乳腺癌细胞细胞侵袭和转移的实验研究

目的观察人参皂甙Rh2对人乳腺癌MCF7/Adr细胞侵袭和迁移的作用及其机制。方法用MTT比色法,检测人参皂甙Rh2(Rh2)对MCF7/Adr细胞的活力;Transwell小室测定其侵袭力和迁移力;Western blot法检测细胞基质金属蛋白酶2(MMP2)、MMP9和核转录因子KappaB(NF-KB)蛋白水平的变化。结果用人参皂甙Rh2处理后,MCF7/Adr细胞生长受到抑制,且作用呈时效-量效依赖关系;同时细胞侵袭和迁移能力明显降低;MMP2、MMP9和NF-kB蛋白的表达均明显减弱。结论人参皂甙Rh2能够减弱MCF7/Adr细胞侵袭和转移,其机制可能与降低MMP2、MMP9和NF-kB蛋白表达有关。     

阿霉素对人乳腺癌细胞凋亡及去磷酸化RB蛋白表达的影响

目的 :探讨阿霉素 (ADR)体外诱导人乳腺癌化疗敏感细胞 (MCF 7 S)凋亡与去磷酸化RB蛋白表达之间的关系。方法 :应用MTT比色法检测ADR对体外培养的MCF 7 S细胞增殖抑制作用 ,同时应用末端标记 (TUNEL)法观测ADR对MCF 7 S细胞凋亡程度的影响。采用免疫细胞化学法检测去磷酸化RB蛋白的表达水平。结果 :ADR抑制MCF 7 S细胞增殖呈剂量依赖性 ,半数抑制浓度 (IC50 )为0 .12 8mg·L-1;ADR作用组MCF 7 S细胞的凋亡率(apoptoticrate ,AR)为 0 .2 6 1,较对照组 (0 .0 4 5 )明显增高 (P <0 .0 1) ;ADR作用组MCF 7 S细胞的去磷酸化RB蛋白表达量MOD(阳性细胞平均光密度 )×area(阳性面积相对比 )均数是 987± 2 0 7,较对照组132± 32显著增高 (P <0 .0 1) ;ADR能促进MCF 7 S细胞内去磷酸化RB蛋白的表达。在ADR作用组 ,MCF 7 S细胞的凋亡率与去磷酸化RB蛋白表达量呈正相关 (P <0 .0 5 )。结论 :ADR抑制MCF 7 S细胞增殖和诱导MCF 7 S细胞凋亡可能与细胞内去磷酸化RB蛋白表达水平有关。     

复方TH抗肿瘤作用研究

目的研究复方TH体内外抗肿瘤活性,筛选抗肿瘤新复方。方法体外采用噻唑蓝（MTT）法检测复方TH对体外培养的人肺癌细胞A549、人食管癌细胞EC9706、人结肠癌细胞LoVo、人肝癌细胞Hep G2、人乳腺癌细胞MCF 7的生长抑制作用,计算生长抑制率及半数抑制浓度（IC50）。将小鼠接种肝癌H22细胞后随机分成5组：空白对照组（双蒸水）、阳性对照组（顺铂0.005 g&#8226;kg 1）、3个剂量复方TH给药组（0.030,0.060,0.090 g&#8226;kg 1）,复方TH组次日开始灌胃给药0.3 mL,连续8 d。每间隔1 d每只小鼠腹腔注射给药0.2 mL,共3次。末次给药后24 h处死小鼠,计算肿瘤抑制率、胸腺指数、脾脏指数。结果复方TH可以显著抑制人肺癌细胞A549、人食管癌细胞EC9706、人结肠癌细胞LoVo、人肝癌细胞Hep G2、人乳腺癌细胞MCF 7的生长,IC50分别为7.15,5.41,2.49,2.18和1.37 μg&#8226;mL 1;TH复方小、中、高剂量组的肿瘤抑制率分别为52.8%,44.9%和47.9%;与对照组比较均差异有极显著性（均P＜0.01）,脏器指数及质量与对照组比较均差异无显著性,与阳性对照组比较差异有极显著性（P＜0.01）。结论复方TH对体外培养的肿瘤细胞有较强的细胞毒性作用,可显著抑制细胞生长;体内可以明显抑制实体瘤生长。     

阿霉素诱导小鼠MCF-7乳腺癌细胞凋亡和抑制增殖的体内实验研究

目的:探讨阿霉素对荷瘤鼠MCF7乳腺癌细胞凋亡和增殖的影响。方法:建立小鼠MCF7乳腺癌细胞模型,用TUNEL法和免疫组化法检测阿霉素作用下MCF7乳腺癌细胞的凋亡和PCNA表达的变化。结果:1.25mg·kg-1阿霉素的抑瘤率为43%。MCF7乳腺癌细胞的凋亡指数为1.93%,较荷瘤对照组的1.11%明显升高(P<0.05)。增殖指数为35.75%,较荷瘤对照组的56.38%明显下降(P<0.01)。结论:阿霉素有诱导小鼠MCF7乳腺癌细胞凋亡和抑制其增殖的作用。     

p-Hydroxybenzoate esters metabolism in MCF7 breast cancer cells

Parabens are among the most frequently used preservatives to inhibit microbial growth and extend the shelf life of a range of consumer products. The objective of the present study was to gain insight into the metabolism of parabens in breast cancer cells (MCF7) since they have demonstrated estrogenic activity towards these cells and have been detected in breast cancer tissues. The toxicity of parabens to MCF7 cells was determined using MTT assays. Hydrolysis of methyl-, butyl and benzyl-paraben to p-hydroxybenzoic acid was analyzed in cultured MCF7 cells and in cellular homogenates. Glucuronidation and sulfoconjugation were studied in MCF7 homogenates, and parabens were analyzed by HPLC. Methyl-paraben was shown to be far less toxic than butyl and benzyl-paraben. Parabens were completely stable in MCF7 homogenates whereas p-nitrophenyl acetate, a substrate type, underwent hydrolysis. MCF7 cell homogenates did not express glucuronidation and sulfoconjugation activities toward parabens. The higher stability of parabens may explain their accumulation in breast cancer tissue as previously reported in the literature.     

Positional isomers of acetaminophen differentially induce proliferation of cultured breast cancer cells

This study demonstrates that acetaminophen (p-acetamidophenol) stimulates proliferation of estrogen-responsive cultured breast cancer cells and assesses if the proliferative activity of p-acetamidophenol is influenced by the -OH moiety position on the benzene ring. The effects of p-, m-, and o-acetamidophenol on cell number and on percentage cells in S phase of the cell cycle were determined for two estrogen receptor positive, human breast cancer cell lines, T47D and MCF7. Therapeutic concentrations of p-acetamidophenol (0.1 mM) significantly increased breast cancer cell proliferation. The relative order of potency of isomers in stimulating proliferation in both cell types was p- > m- > o-acetamidophenol, indicating the -OH position on the benzene ring influences the proliferation output in cultured breast cancer cells.     

Bcl-2基因反义寡核苷酸对乳腺癌细胞株药物敏感性的影响

目的:探讨bcl-2基因反义寡核苷酸对人乳腺癌细胞株MCF-7的bcl-2蛋白的表达和药物敏感性的影响.方法:用人工合成bcl-2基因反义寡核苷酸预培养人乳腺癌细胞株MCF-7,以免疫组化法检测细胞bcl-2蛋白的表达水平;以MTT法检测bcl-2反义寡核苷酸、阿霉素单独及联合应用对MCF-7细胞生长的抑制情况,比较bcl-2蛋白表达与肿瘤细胞药物敏感性之间的相关性.结果:联合应用bcl-2反义寡核苷酸与阿霉素能够明显增加MCF-7细胞对阿霉素的敏感性,细胞存活率明显下降.免疫组化结果显示MCF-7细胞bcl-2表达水平与细胞药物敏感性有相关性.结论:bcl-2反义寡核苷酸能够抑制MCF-7乳腺癌细胞bcl-2基因的表达,提高MCF-7细胞对阿霉素的敏感性.     

CDK9抑制剂F200对乳腺癌细胞MCF7凋亡的影响

目的研究细胞周期依赖性激酶（cell cycle dependent kinase,CDK）CDK9抑制剂F200对乳腺癌细胞MCF7凋亡的影响。方法 MCF7细胞培养于含0.01 mg·mL^-1人重组胰岛素及10%胎牛血清的RPMI 1640培养液中,待对数生长期时接种细胞进行实验,24 h贴壁后给药：分为阴性对照组（0.5%DMSO）、阳性对照组（R-Roscovitine 5.66μM）及药物组（F200 0.1μM,0.71μM）,给药48 h后利用TUNEL法染色观察细胞凋亡DNA断裂情况及细胞凋亡形态学变化、流式细胞技术检测细胞的凋亡比率、免疫印迹法检测凋亡标志蛋白PARP的表达情况。结果 TUNEL结果显示,随着F200浓度增加,细胞出现明显的固缩变圆,细胞核可见深染致密颗粒,细胞核质分界明显等凋亡表现;流式细胞仪结果显示,0.71μM的F200能够诱导32.6%的细胞凋亡;Western Blot结果显示,随着F200浓度增加,PARP蛋白剪切水平明显增加。结论 F200能有效促进乳腺癌细胞MCF7的凋亡。     

The Role of Waixenicin A as Transient Receptor Potential Melastatin 7 Blocker

Transient receptor potential melastatin 7 (TRPM7) plays a role in a number of physiological and pharmacological functions in variety of cells. The aim of this study was to clarify the role for TRPM7 channels and the effect of waixenicin A on the pacemaking activity of interstitial cells of Cajal (ICCs) and on the cell viability of the human gastric and breast adenocarcinoma cell lines, AGS and MCF‐7, respectively. Waixenicin A decreased the amplitude of pacemaker potentials in cultured ICC clusters and inhibited TRPM7 currents, but had no effect on Ca²⁺‐activated Cl^? conductance (ANO1). Furthermore, waixenicin A was found to inhibit the growth and survival of AGS and MCF‐7 cells. These findings indicate that TRPM7 channel modulates intestinal motility and regulates the pathophysiology of human gastric and breast adenocarcinoma cells. These findings suggest that TRPM7 channel be considered a potential target for the treatment of gut motor disorders and gastric and breast cancer.     

Peroxisome proliferator-activated receptor-beta/delta (PPARbeta/delta) ligands inhibit growth of UACC903 and MCF7 human cancer cell lines

The development of peroxisome proliferator-activated receptor-beta/delta (PPARbeta/delta) ligands for the treatment of diseases including metabolic syndrome, diabetes and obesity has been hampered due to contradictory findings on their potential safety. For example, while some reports show that ligand activation of PPARbeta/delta promotes the induction of terminal differentiation and inhibition of cell growth, other reports suggest that PPARbeta/delta ligands potentiate tumorigenesis by increasing cell proliferation. Some of the contradictory findings could be due in part to differences in the ligand examined, the presence or absence of serum in cell cultures, differences in cell lines or differences in the method used to quantify cell growth. For these reasons, this study examined the effect of ligand activation of PPARbeta/delta on cell growth of two human cancer cell lines, MCF7 (breast cancer) and UACC903 (melanoma) in the presence or absence of serum using two highly specific PPARbeta/delta ligands, GW0742 or GW501516. Culturing cells in the presence of either GW0742 or GW501516 caused upregulation of the known PPARbeta/delta target gene angiopoietin-like protein 4 (ANGPTL4). Inhibition of cell growth was observed in both cell lines cultured in the presence of either GW0742 or GW501516, and the presence or absence of serum had little influence on this inhibition. Results from the present studies demonstrate that ligand activation of PPARbeta/delta inhibits the growth of both MCF7 and UACC903 cell lines and provide further evidence that PPARbeta/delta ligands are not mitogenic in human cancer cell lines.     

The nucleoside antagonist cordycepin causes DNA double strand breaks in breast cancer cells

The fungal drug cordycepin (3-deoxyadenosine) is known to exert anti-tumor activities, preferentially by interfering with RNA synthesis. We have investigated the effect of cordycepin on human breast epithelial cell lines, ranging from non-malignant MCF10A cells to highly de-differentiated MDA-MB-435 cancer cells. Treatment of human breast cancer cells with cordycepin caused either apoptosis or persistent cell cycle arrest that was associated with reduced clonal growth of cordycepin-treated breast cancer cells. Highly de-differentiated breast cancer cell lines, such as MDA-MB-231 and MDA-MB-435, reacted more sensitive to cordycepin than less aggressive breast cancer cell lines (MCF7, T47D) or non-malignant breast epithelial cells (MCF10A), which poorly reacted to cordycepin. In cordycepin-sensitive breast cancer cells, a marked induction of the DNA damage response (DDR), including the phosphorylation of ATM, ATR, and histone γH2AX could be observed. These data indicate that cordycepin, which was believed to cause cancer cell death by inhibition of RNA synthesis, induces DNA double strand breaks in breast cancer cells. The genotoxic effect of cordycepin on breast cancer cells indicates a new mechanism of cordycepin-induced cancer cell death, and its activity against highly undifferentiated breast cancer cells provides a new perspective of how cordycepin may be used in the treatment of advanced breast cancer.     

The predictive value of epidermal growth factor receptor expression for sensitivity to vinorelbine in breast cancer

Abstract: Breast cancer patients with positive epidermal growth factor receptor (EGFR) expression have significantly worse post‐relapse prognosis than patients with negative EGFR expression. Vinorelbine (NVB) is usually reserved as a salvage therapy after anthracyclines and taxanes in patients with breast cancer. To see whether EGFR expression has a predictive value in NVB‐mediated effect on human breast cancer cells, we examined 50 primary breast cancer samples. Of these, 42% were found to be NVB sensitive by ATP‐tumour chemosensitivity assay. Sensitivity was correlated with EGFR expression level (p = 0.001). To dynamically examine EGFR’s effect on NVB sensitivity in breast cancer cells, we used the real‐time cell electronic sensing system with EGFR‐positive and EGFR‐negative breast cancer cell lines, MCF‐7 and MDA‐MB‐435s, respectively. MCF‐7 is NVB sensitive, while MDA‐MB‐435 is NVB resistant. NVB‐induced cytotoxicity to MCF‐7 can be partly reversed with inhibitory anti‐EGFR antibody. NVB up‐regulated EGFR expression in MCF‐7 cells, which affects ERK1/2 phosphorylation. This cellular response mechanism may cause greater input to non‐lethally damaged cells. These data suggest that EGFR expression can be used as a prognostic factor for breast cancer sensitivity to NVB, which could help identify appropriate treatments for breast cancer.