茶氨酸衍生物茶溴香酰胺脂质体对人肺癌细胞 生长和迁移的抑制作用

为了探索研究茶氨酸衍生物茶溴香酰胺制备的脂质体(TBrC-L)对人非小细胞肺癌A549细胞生长和迁移的抑制作用与其分子机制,采用薄膜分散法制备了TBrC-L,通过MTT法检测不同浓度的TBrC-L对人肺癌A549细胞生长的抑制作用;使用流式细胞术检测TBrC-L对人肺癌A549细胞凋亡的诱导作用;利用Transwell chamber法观察TBrC-L对人肺癌A549细胞迁移作用的影响;应用蛋白质印迹法检测人肺癌A549细胞中与凋亡和生长密切相关蛋白的表达和药物可能的作用靶点。实验结果显示,TBrC-L对人肺癌A549细胞生长和迁移有显著的抑制作用,促进肿瘤细胞凋亡、抑制肿瘤细胞生长和迁移可能是其抗人肺癌作用的重要机制,其作用的分子机制涉及到抑制EGFR、VEGFR1、VEGFR~2和Met受体介导的Akt和NF-κB信号传导通路,本研究结果提示,TBrC-L具有应用于临床治疗和(或)辅助治疗人肺癌的潜力。     

茶氨酸和其衍生物茶氨酸氯香酰胺对高转移的 人乳腺癌细胞生长的抑制作用

旨在评估茶氨酸（T）和本实验室合成的新颖的茶氨酸衍生物-茶氨酸氯香酰胺（TClC）对高转移的人乳腺癌MDA-MB-231细胞生长的抑制作用,并对其作用的机制进行初步探究。采用MTT法检测不同浓度的T和TClC对MDA-MB-231细胞体外生长的影响,采用Western blotting对MDA-MB-231细胞中与癌细胞凋亡相关蛋白的表达以及药物作用可能的分子靶点进行检测。结果显示,随着浓度的增高,T和TClC对人乳腺癌MDA-MB-231细胞体外生长的抑制作用逐渐增强, TClC的抑制作用要明显强于T;T和TClC均能够下调抗凋亡蛋白Bcl-2的表达水平,同时上调促凋亡蛋白Bax的表达水平,使Bcl-2/Bax比率减少。此外,T和TClC均能抑制血管内皮生长因子受体VEGFR1和核转录因子NF-κB的表达, 而TClC的抑制作用要明显强于T。T和TClC对这些蛋白水平的调节作用可能是抑制MDA-MB-231细胞生长的重要机制之一。这些结果表明,T和TClC对治疗高转移的人乳腺癌可能具有广阔的应用前景。     

茶双溴香酰胺对人宫颈癌细胞生长的抑制 与其作用的分子机制

以茶氨酸为对照,探索研究以茶氨酸为原料合成的新的衍生物茶双溴香酰胺(DTBrC)对高转移的人宫颈癌细胞生长的抑制作用与其分子机制。采用MTT法检测不同浓度的DTBrC对人宫颈癌细胞生长的影响;应用蛋白质印迹法检测这些人宫颈癌细胞中与凋亡和生长密切相关蛋白的表达和药物可能的作用靶点。结果显示,DTBrC抑制人宫颈癌细胞生长的活性超过其母体化合物茶氨酸7倍;DTBrC明显抑制血管内皮生长因子受体VEGFR2和转录因子NF-κB蛋白的表达,显著减少蛋白激酶Akt的表达和磷酸化水平,降低抗凋亡蛋白Bcl-2水平,提高促凋亡蛋白Bax表达,从而减少Bcl-2/Bax比率。DTBrC作用的分子机制可能与抑制VEGFR2-Akt/NF-κB信号传导通路相关。本研究结果提示,DTBrC具有应用于临床治疗和(或)辅助治疗高转移人宫颈癌的潜力。     

合成的新茶氨酸衍生物茶双溴香酰胺 对人乳腺癌细胞生长的抑制作用

为提高茶氨酸的活性,开发新型抗肿瘤药物,合成了新的茶氨酸衍生物茶双溴香酰胺(DTBr C),比较茶氨酸和茶双溴香酰胺对高转移的人乳腺癌MDA-MB-231细胞生长的抑制作用与其分子机制。采用MTT方法检测不同浓度的DTBr C对MDA-MB-231细胞生长的影响,应用蛋白质印迹法检测解析MDA-MB-231细胞中与凋亡和生长密切相关蛋白的表达和药物可能的作用靶点。结果表明,DTBr C抑制MDA-MB-231细胞生长的活性超过其母体化合物茶氨酸多倍;DTBr C显著减少抗凋亡蛋白Bcl-2水平,大大提高促凋亡蛋白Bax表达,从而减少Bcl-2/Bax比率;此外,DTBr C明显抑制血管内皮生长因子受体VEGFR2和蛋白激酶Akt的表达及磷酸化,DTBr C对这些蛋白的作用活性强于茶氨酸。DTBr C作用机制可能与抑制MDA-MB-231细胞VEGFR2-Akt信号传导通路相关。本研究结果提示,DTBr C可能具有广泛应用于临床治疗和(或)辅助治疗高转移乳腺癌的潜力。     

MTT法检测灰直纹螟-青钱柳虫茶对肿瘤细胞体外增殖抑制作用

为了获得优质的灰直纹螟-青钱柳虫茶以及明确其对人乳腺癌细胞MCF-7、胃癌细胞SGC-7901增殖抑制作用。用青钱柳叶片饲养灰直纹螟后,将其幼虫所排出的代谢物经过不同规格筛网筛选分离和紫外杀菌后获得优质虫茶,将获得的虫茶制备成不同浓度去处理体外培养的MCF-7和SGC-7901癌细胞,采用MTT法检测虫茶体外对MCF-7和SGC-7901癌细胞的增殖抑制作用。结果表明,灰直纹螟-青钱柳虫茶对人乳腺癌细胞MCF-7和胃癌细胞SGC-7901具有明显的抑制作用,但抑制效果并不完全相同,处理24 h后虫茶对人乳腺癌细胞MCF-7的增殖抑制效果更好。虫茶对人乳腺癌细胞MCF-7、胃癌细胞SGC-7901具有明显的抑制作用,其抑制率与浓度及处理时间呈正相关。     

紫草素诱导乳腺癌细胞凋亡的研究

以MTT法测定紫草素对乳腺癌细胞株MCF-7等的生长抑制作用,并通过形态学分析、Hoechst荧光染色、流式细胞术及免疫印迹等观察紫草素诱导乳腺癌细胞凋亡的形态学、生化特征改变及凋亡的可能机制.结果表明:紫草素对乳腺癌细胞株有显著抑制生长作用,效应呈时间和剂量的依赖性,24h半数抑制浓度(IC50)均在10μmol·L-1以下.紫草素诱导MCF-7等乳腺癌细胞发生典型的细胞凋亡,细胞周期阻滞于S期,凋亡过程中产生了85ku大小的PARP裂解片段,此效应可被广谱caspase抑制剂抑制,表明紫草素可能经caspase途径诱导MCF-7细胞发生凋亡.     

牡丹种皮乙酸乙酯提取物抗癌活性研究

研究了牡丹种皮乙酸乙酯提取物对人源性乳腺癌细胞株(MCF-7)的增殖抑制率及细胞活性的影响。制备不同浓度梯度的牡丹种皮乙酸乙酯提物作用于MCF-7细胞,通过细胞形态学分析,AO/PI双染色,MTT法和线粒体膜电位法检测MCF-7细胞的生长活力,增殖抑制能力和线粒体膜电位变化。研究结果表明,当牡丹种皮乙酸乙酯提物质量浓度为5 mg/mL时,对MCF-7细胞的抑制效果最佳,细胞抑制率可达89.67%,并且在药物作用下,细胞活性和线粒体膜电位均明显下降。牡丹种皮乙酸乙酯提取物对乳腺癌细胞MCF-7的生长有抑制作用,能够降低细胞活性,促使MCF-7细胞线粒体膜电位降低,诱导细胞产生凋亡现象。     

茶氨酸溴香酰胺对人肝癌细胞体内外生长的抑制作用

以L-茶氨酸作对照,评估本实验室合成的新颖的茶氨酸衍生物-茶氨酸溴香酰胺（TBrC）对人肝癌HepG2细胞系体内外生长的抑制作用,并初步探究其作用的分子机制。采用MTT法检测不同浓度的TBrC对HepG2细胞体外生长的影响,应用蛋白质印迹法检测解析HepG2细胞中与癌细胞凋亡和生长密切相关蛋白的表达和药物可能作用的分子靶点。此外,建立动物肿瘤模型,与对照组茶氨酸和临床常用抗癌药物五氟尿嘧啶组相比较,评价TBrC对荷瘤裸鼠人肝癌HepG2肿瘤生长的抑制效果。实验结果显示,TBrC抑制人肝癌细胞体内外生长的活性超过其母体化合物茶氨酸分别为3倍和4倍以上,对小鼠生长无明显毒性。TBrC比茶氨酸更显著地抑制肝癌细胞生长因子受体c-Met和抗凋亡的Bcl-2等蛋白的表达;此外,TBrC大大上调促进凋亡的Bax蛋白的表达。TBrC抑制c-Met信号传导通路,下调Bcl-2/Bax蛋白比率可能是其作用的分子机制之一。这些结果提示,TBrC具有广泛应用于临床治疗和（或）辅助治疗人肝癌和其他癌症的潜力。     

中药防风对胃癌SGC-7901细胞生长及基因表达的研究

目的研究中药防风对胃癌SGC-7901细胞生长及基因表达的影响．方法应用集落形成实验、MTT实验及电子显微镜技术观察了防风对SGC-7901细胞生长的影响;应用免疫组织化学染色技术研究防风对SGC-7901细胞基因表达的影响．结果防风对SGC-7901细胞的生长曲线、集落形成有明显的抑制作用,其抑制作用与防风的浓度和时间呈正相关关系,其IC50值为24g／mL．防风能使SGC-7901细胞p16和p21编码基因的蛋白表达上调,PCNA,C—Met编码基因的蛋白表达下调．结论防风能抑制SGC-7901细胞生长;防风可使SGC-7901细胞的p16,p21,PCNA,C—Met表达改变．这些结果为防风在临床上的进一步应用提供了理论依据．     

女性 母性 人性——莫言长篇小说《蛙》中“姑姑”的性属隐喻

为了更好地理解镉对人体的健康效应以保障人体健康，以典型天然雌激素雌二醇(E2)为代表，研究了E2与Cd的共同作用效应.主要研究了人体乳腺癌细胞MCF-7增殖、周期分析、雌激素活性作用途径等.结果发现Cd具有雌激素活性，但与E2共存时发生拮抗作用，雌激素活性明显下降.细胞周期研究表明，E2，Cd及两者混合物均能提高DNA合成期细胞比例，促进细胞增殖.增殖途径分析表明，E2，Cd及其混合物使细胞内雌激素受体α(ERα)蛋白的表达量明显降低，拮抗作用的发生主要来自丝裂原活化蛋白激酶(MAPK)信号转导通路.E2和Cd可以诱导增殖相关蛋白Ki67的表达，促进细胞增殖，而E2与Cd联合使Ki67的表达极大地降低.     

Transfection of v-rasH DNA into MCF-7 human breast cancer cells bypasses dependence on estrogen for tumorigenicity

The natural history of estrogen-responsive breast cancers often involves a phenotypic change to an estrogen-unresponsive, more aggressive tumor. The human breast cancer cell line, MCF-7, which requires estradiol for tumor formation in vivo and shows growth stimulation in response to estradiol in vitro, is a model for hormone-responsive tumors. The v-rasH onc gene was transfected into MCF-7 cells. The cloned MCF-7ras transfectants, which expressed the v-rasH messenger RNA and v-rasH p21 protein (21,000 daltons), were characterized. In contrast to the parental cell line, MCF-7ras cells no longer responded to exogenous estrogen in culture and their growth was minimally inhibited by exogenous antiestrogens. When tested in the nude mouse, the MCF-7ras cells were fully tumorigenic in the absence of estrogen supplementation. Thus, cells acquiring an activated onc gene can bypass the hormonal regulatory signals that trigger the neoplastic growth of a human breast cancer cell line.     

Lactic Acid Reduces LPS-Induced TNF-α and IL-6 mRNA Levels Through Decreasing IKBα Phosphorylation

This study explored the effects over time of lactic acid (LA) on I _κBα phosphorylation and nuclear factor-kappa B (NF-κB) p65 protein expression, and on tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) mRNA levels in rat intestinal mucosa microvascular endothelial cells (RIMMVECs) stimulated by lipopolysaccharide (LPS). IκBα, phosphorylated IκBα (ρ-I _κBα) and p65 protein levels were monitored by Western blot analysis, and TNF-α and IL-6 mRNA levels were analyzed using real-time PCR. LA treatment reduced TNF-α and IL-6 mRNA levels in LPS-stimulated RIMMVECs, with the greatest effect being after 3 h. The highest inhibitory effect of LA on I _κBα phosphorylation to prevent activation of NF- _κB was after 6 h. These results suggest that LA reduces TNF-α and IL-6 mRNA levels through decreasing IκBα phosphorylation and blocking the dissociation of IKK complex, which prevents activation of NF- _κB.     

N-乙酰半胱氨酸对双酚A诱导的猪肾细胞凋亡和炎症反应的抑制作用

【背景】双酚A(BPA)广泛应用于塑料材料工业制造,其从塑料制品中渗出,暴露在食物、水、土壤和空气等多种环境介质中,导致动物长期接触,并经过胎盘和母乳传递给后代,干扰动物生长和发育,对动物生长性能和生产效率产生不利影响。N-乙酰半胱氨酸（NAC）作为公认的强效抗氧化剂,能够调节氧化应激、细胞凋亡、炎症等多种病理生理过程。然而,NAC对BPA诱导的猪肾细胞损伤的调节作用尚不清楚。【目的】探究抗氧化剂NAC在BPA诱导的PK15细胞凋亡和炎症反应中的潜在作用,为NAC在对抗BPA诱导的猪肾细胞损伤中的应用研究提供科学依据。【方法】选取PK15细胞为试验材料,采用相应的抗氧化检测试剂盒分别测定细胞内过氧化氢酶（CAT）、总超氧化物歧化酶（T-SOD）和谷胱甘肽过氧化物酶（GSH-Px）活性变化;设置不同浓度NAC(0、2、5和10 mmol·L-1)预处理,并与BPA共处理PK15细胞,CCK-8检测细胞活力以筛选最佳的NAC作用浓度;实时荧光定量PCR(qRT-PCR)检测凋亡相关基因（BAX、BCL-2和Caspase3）表达和炎症相关基因（IL-8、IL-6、IL-1β和TNF-α）m...     

人乳腺癌细胞、结肠癌细胞和宫颈癌细胞生长曲线测定

为检测比较人乳腺细胞(MDA-MB-231、MCF-7、HBL-100)、人结肠癌细胞(HCT-8)和人宫颈癌细胞(HeLa)生长曲线的差异性.本实验首先常规培养MDA-MB-231、MCF-7、HBL-100、HCT-8和HeLa细胞,然后应用MTT方法测定这几种细胞的生长曲线.在本实验条件下,这几种细胞生长速度从高...     

Estrogen-induced factors of breast cancer cells partially replace estrogen to promote tumor growth

The hormone 17 beta-estradiol acts through its receptor system to induce MCF-7 human breast cancer cells to form tumors in athymic mice. In vitro studies have identified the production of estrogen-induced growth factors from MCF-7 cells that may have a role in growth control. These induced growth factors were sufficient to stimulate MCF-7 tumor growth in ovariectomized athymic mice, thus partially replacing estradiol. Growth factors may act as estrogen-induced "second messengers" in estrogen-responsive growth of human breast cancer.     

Changes of NF-κB,Bax and Caspase 3 in Apoptosis Induced by Ligustrazine Combined with Cis-dichlorodiamine Platinum in Human Gastric Carcinoma SGC-7901 Cell Lines

[Objective] This study aimed to investigate the mechanism of apoptosis induced by ligustrazine(TMP) and cis-dichlorodiamine platinum(DDP) in SGC-7901 cell lines in vitro. [Methods] SGC-7901 cell lines were treated with ligustrazine and DDP alone or combined for 48 h for Western blot analysis, respectively. Western blot analysis was used to determine the expression of proteins involved in apoptosis including NF-κB p65, bax and caspase-3. [Results] The viability of SGC-7901 cells was inhibited after treated with ligustrazine and/or combined with DDP. The expression of NF-κB P65 protein decreased after treated with drugs, in which the protein decreased significantly in 1.2 mg/ml of TMP combined with 2 μg/ml of DDP group.Meanwhile, we investigated the protein expression of bax and caspase-3. The results showed that the expression of the two proteins increased following with the increasing concentration of TMP. [Conclusion] All the results indicated that ligustrazine combined with DDP could induce the apoptosis of SGC-7901 cell lines, and NF-κB maybe the possible way to induce the cell apoptosis.     

无刺蜂蜂胶乙醇提取物的体外抗氧化及抗炎活性

【目的】 无刺蜂(stingless bees)是热带和亚热带地区重要的授粉昆虫之一,以尾部无蛰针为典型特征,其蜂胶采集量较意大利蜜蜂（ Apis mellifera ligustica ）更多,然而其蜂胶活性研究却相对匮乏。本文以来源于马来西亚无刺蜂 ( Heterotrigona itama )采集蜂胶的乙醇提取物(ethanol extract of H. itama propolis, EEHI)为研究对象,旨在探究其体外抗氧化和抗炎活性。【方法】 采用福林酚法和硝酸铝法测定EEHI中总酚酸和总黄酮含量,并采用DPPH和ABTS ^+·自由基清除能力评价EEHI的体外抗氧化能力;在此基础上,采用细菌脂多糖(LPS)诱导小鼠巨噬细胞RAW 264.7炎症模型,通过CCK-8法检测EEHI对细胞相对存活率的影响,在保证EEHI对细胞无细胞毒性作用基础上,分别采用Griess法和实时荧光定量PCR（RT-qPCR）技术评估EEHI对LPS诱导的RAW 264.7细胞中炎症介质一氧化氮（NO）释放量的影响以及其对炎症因子（ IL-1β 、 IL-10 和 INOS ）和抗氧化基因（ HO-1 ）信使RNA表达的影响;进一步利用免疫印迹和免疫荧光方法,以NF-κB炎症信号通路为切入点,研究EEHI对LPS诱导巨噬细胞中p-IκΒ α 和IκΒ α 蛋白表达以及NF-κB-p65蛋白移位的影响,从而探究EEHI潜在的抗炎机理。 【结果】 EEHI中总酚酸和总黄酮含量分别为54.70 mg GAE·g^-1和116.20 mg QE·g^-1;DPPH和ABTS^+·自由基清除能力IC₅₀值分别为275.60和 284.00 μg·mL^-1。EEHI对RAW 264.7细胞的安全浓度为0—40 μg·mL^-1。在LPS诱导的Raw 264.7细胞炎症模型中,相对于LPS刺激组,0—40 μg·mL^-1的EEHI以浓度依赖方式显著地抑制了LPS诱导的RAW 264.7细胞中NO的释放量,且降低了细胞中炎症因子 IL-1β 、 IL-10 和 INOS 的基因表达量,并增强了抗氧化基因 HO-1 的表达。进一步研究发现,0—40 μg·mL^-1的EEHI以浓度依赖方式显著抑制了LPS诱导的RAW 264.7细胞IκΒ α 蛋白的磷酸化,且40 μg·mL^-1的EEHI显著降低了NF-κB-p65蛋白的核移位现象,因此推测EEHI可能是通过抑制LPS诱导的NF-κB信号通路的激活进而发挥了体外抗炎活性。 【结论】 无刺蜂蜂胶乙醇提取物中含有大量多酚类化合物,具有较好的抗炎和抗氧化效果,极具开发利用价值。     

Lactic Acid Inhibits NF-κB Activation by Lipopolysaccharide in Rat Intestinal Mucosa Microvascular Endothelial Cells

To investigate whether lactic acid could inhibit the LPS-activation of NF-κB p65 in rat intestinal mucosa microvascular endothelial cells (RIMMVECs), RIMMVECs, cultured in vitro, were pretreated with different concentrations of lactic acid and then exposed to lipopolysaccharide (LPS). Cells and cell culture media were then collected at different time intervals. Production of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) was examined at the protein level by enzyme-linked immunosorbent assay. The influence of lactic acid on the LPS-activation of NF-κB was examined at mRNA and protein levels by real-time quantitative PCR and Western blot analysis, respectively. TNF-α and IL-6 protein levels were significantly decreased after pretreatment with lactic acid compared with cells exposed to LPS only. After pretreatment with 7.5, 5.0, and 2.5 μL mL-1 lactic acid, NF-κB mRNA levels were increased by 1.51-, 2.62- and 3.00-fold, respectively, compared with levels in control cells without LPS treatment. Western blot analysis indicated that the level of NF-κB p65 in the lactic acidpretreated group was significantly lower than that in the group treated with LPS only (positive control) and was unchanged compared with the group without LPS treatment (blank control). These results suggest that lactic acid may inhibit LPSactivation of NF-κB, leading to the down-regulation of TNF-α and IL-6.     

Human breast cancer: androgen action mediated by estrogen receptor

Growth of the human breast cancer cell line MCF-7 is enhanced by androgens, but only at pharmacological concentrations. Although physiological concentrations of androgens translocate the androgen receptor into the nucleus, no mitogenic effects are observed. By contrast, pharmacological androgens translocate not only the androgen receptor but also the estrogen receptor, and at these high doses significantly increase both DNA and estrogen-dependent protein synthesis. We therefore propose that androgens stimulate MCF-7 cell growth not through the androgen receptor but rather through the estrogen receptor.