光照对姜黄素诱导人乳腺癌MCF-7细胞凋亡的影响

目的 研究光照对姜黄素诱导人乳腺癌MCF-7细胞凋亡的影响,探讨其作为肿瘤光动力学治疗新型光敏剂的可能性.方法 体外培养的MCF-7细胞加姜黄素后进行光照及避光处理24h,MTT法测细胞生长抑制率,Giemsa、Hoechst33258染色观察形态变化,流式细胞术检测凋亡率和细胞周期分布.结果 单纯光照对MCF-7细胞无生长抑制及诱导凋亡作用,光照及避光条件下姜黄素对MCF-7细胞生长抑制的IC50分别为2.68、13.44 μmol/L;细胞在光照条件下经5μmol/L姜黄素处理24h即呈现典型的凋亡形态;光照条件下1、2.5、3、5 10 μmol/L姜黄素及避光条件下5、10、15、20、30μmol/L姜黄素处理细胞24h,凋亡率分别为4.06%、16.79%、19.46%、35.97%、59.27及5.71%、8.88%、12.51%、38.04%、26.60%;姜黄素在光照及避光条件下均可引起细胞周期分布发生改变.结论 光照对姜黄素抑制MCF-7细胞生长及诱导凋亡具有增敏作用.     

A novel nuclear form of estradiol receptor in MCF-7 human breast cancer cells

Nuclear estrogen receptor from MCF-7 cells undergoes a time-dependent, hormone-inducible transformation to a form that is less extractable from nuclei and less exchangeable with ligand. This receptor-modifying, intranuclear event is independent of receptor loss (processing) and appears associated with hormone responsiveness (progesterone-receptor induction) in these cells. The magnitude of receptor loss, however, is variable and apparently not a prerequisite for hormone action to induce progesterone receptor.     

二甲双胍、罗格列酮或联合应用对乳腺癌MCF-7细胞周期和凋亡的影响

目的 观察二甲双胍单药、罗格列酮或联合应用对乳腺癌MCF-7细胞周期和凋亡的影响.方法 用浓度为20 mmol/L二甲双胍(二甲双胍组)、100 μmol/L罗格列酮(罗格列酮)及二甲双胍联合罗格列酮(联合用药组)处理MCF-7细胞48h,分别采用MTT法、流式细胞术、Hoechst33258染色法观察细胞增殖、周期、凋亡情况.结果 二甲双胍组、联合用药组的MCF-7细胞增殖被显著抑制,二甲双胍组、罗格列酮组、联合用药组阻滞MCF-7细胞于G0/G1期比例增加,S、G2/M期比例减少,二甲双胍组、罗格列酮组、联合用药组的细胞早期凋亡率分别为(15.3±1.09)％、(12.4±1.73)％、(17.2±1.63)％,与对照组比较差异有统计学意义(P＜0.01).结论 单用二甲双胍或联合罗格列酮均能抑制MCF-7细胞的增殖,诱导其细胞周期停滞和凋亡.     

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.     

重组质粒pDsRed1-C1-PinX1的建立及其在乳腺癌MCF-7细胞中的表达

目的构建PinX1真核表达载体,观察PinX1基因对乳腺癌MCF-7细胞生长和增殖的影响。方法重组质粒转染MCF-7细胞并筛选稳定表达系;用Real-timePCR检测PinX1基因mRNA的表达;MTT法检测转染前后细胞生长变化;平板克隆形成试验检测PinX1对MCF-7集落形成能力的影响。结果构建了真核表达载体PDsRed1-C1-PinX1的稳定表达系;转染后乳腺癌MCF-7细胞生长明显减缓,集落形成能力降低。结论 PinX1基因可抑制乳腺癌MCF-7细胞的生长和增殖。     

抗癌肽改造及其对人乳腺癌MCF7作用的评估

为了探讨不同净电荷及疏水度对天然多肽CMAP-8衍生物抗人乳腺癌细胞MCF7增殖抑制作用的影响,分别采用带正电荷的K和疏水性的F两种氨基酸对天然多肽CMAP-8进行设计改造,得到系列衍生物。其净电荷数为0~8,疏水度为42%~57%,采用MTT法检测所得多肽衍生物对人乳腺癌细胞MCF7的增殖抑制率,Anti CP对多肽抗癌活性的预测。结果表明,净电荷为0的多肽均没有预测抗肿瘤活性,可能是因为多肽的净电荷对其预测活性有一定的影响。体外抗乳腺活性结果表明,CMAP-L-20、CMAP-L-23、CMAP-L-24和CMAP-L-25对MCF7细胞的抑制率与CMAP-8相比,差异达到了极显著水平(Duncan-test,P0.01)。所筛选的4条多肽净电荷数为6~8,疏水度均为46%,而天然多肽CMAP-8净电荷为0,疏水度为42%。多肽活性预测结果与体外抗乳腺癌检测结果一致,共同表明了净电荷的改变对多肽抗乳腺癌活性的影响更大,而疏水度并非越大越好,应该处在合适的范围内。     

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。     

Sequence and expression of human estrogen receptor complementary DNA

The mechanism by which the estrogen receptor and other steroid hormone receptors regulate gene expression in eukaryotic cells is not well understood. In this study, a complementary DNA clone containing the entire translated portion of the messenger RNA for the estrogen receptor from MCF-7 human breast cancer cells was sequenced and then expressed in Chinese hamster ovary (CHO-K1) cells to give a functional protein. An open reading frame of 1785 nucleotides in the complementary DNA corresponded to a polypeptide of 595 amino acids and a molecular weight of 66,200, which is in good agreement with published molecular weight values of 65,000 to 70,000 for the estrogen receptor. Homogenates of transformed Chinese hamster ovary cells containing a protein that bound [3H]estradiol and sedimented as a 4S complex in salt-containing sucrose gradients and as an 8 to 9S complex in the absence of salt. Interaction of this receptor-[3H]estradiol complex with a monoclonal antibody that is specific for primate ER confirms the identity of the expressed complementary DNA as human estrogen receptor. Amino acid sequence comparisons revealed significant regional homology among the human estrogen receptor, the human glucocorticoid receptor, and the putative v-erbA oncogene product. This suggests that steroid receptor genes and the avian erythroblastosis viral oncogene are derived from a common primordial gene. The homologous region, which is rich in cysteine, lysine, and arginine, may represent the DNA-binding domain of these proteins.     

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。     

Recognition of HLA-A2 by cytotoxic T lymphocytes after DNA transfer into human and murine cells

A gene coding for the major histocompatibility antigen HLA-A2 was transferred into human HLA-A2 negative M1 cells and murine L cells. Following transfection, these cells expressed molecules at the cell surface that are biochemically indistinguishable from HLA-A2 antigens on the human cell line JY from which the HLA-A2 gene was isolated. The M1A2 cells were recognized and lysed by a cytolytic T-cell clone specific for HLA-A2. The transfected L cells which express HLA-A2 in association with human beta 2-microglobulin were not lysed by this T-cell clone. The specific cytolysis of M1A2 cells could be inhibited by monoclonal antibodies to HLA-A2, and monoclonal antibodies to T3, T8, and LFA-1 on cytotoxic T lymphocytes. These results suggest that killing by allospecific T cells requires HLA-A2 antigens as well as other species-specific structures on the target cell surface.     

Growth arrest and morphological change of human breast cancer cells by dibutyryl cyclic AMP and L-arginine

The growth in vitro of human breast cancer cells, line MCF-7, was inhibited by a daily supplement of L-arginine (1 milligram per milliliter). Arginine acted synergistically with dibutyryl adenosine 3',5'-monophosphate (cyclic AMP) (10(-6) molar) to enhance the growth inhibitory effect: the cell replication ceased completely within 2 days after treatment. The growth arrest accompanied a change in cell morphology and was preceded by increases in the cellular concentration of cyclic AMP, adenylate cyclase, and type II cyclic AMP-dependent protein kinase activities as well as a decrease of estrogen binding activity. The results suggest that growth of human breast cancer cells is subject to cyclic AMP-mediated regulation and that arginine may play a specific role in this process.     

Formaldehyde damage to DNA and inhibition of DNA repair in human bronchial cells

Cultured bronchial epithelial and fibroblastic cells from humans were used to study DNA damage and toxicity caused by formaldehyde. Formaldehyde caused the formation of cross-links between DNA and proteins, caused single-strand breaks in DNA, and inhibited the resealing of single-strand breaks produced by ionizing radiation. Formaldehyde also inhibited the unscheduled DNA synthesis that occurs after exposure of cells to ultraviolet irradiation or to benzo[a]pyrene diolexpoxide but at doses substantially higher than those required to inhibit the resealing of x-ray-induced single-strand breaks. Therefore, formaldehyde could exert its mutagenic and carcinogenic effects by both damaging DNA and inhibiting DNA repair.     

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。     

Loss of radioactivity from labeled DNA of primary human amnion cells

Primary human amnion cultures labeled with glycine-2-C(14) or thymidine-2-C(14) released more radioactivity into the media than could be accounted for by cell replacement. This is interpreted as degradation of acid-insoluble polydeoxynucleotides in a living human cell.     

阳和汤对裸鼠移植性乳腺癌骨转移模型作用机制的探讨

目的探讨阳和汤对裸鼠移植性人乳腺癌骨转移模型的作用及其相关调节因子的影响。方法股骨接种人 乳腺癌细胞建立裸鼠乳腺癌骨转移模型。随机分为阳和汤高、低剂量组、唑来磷酸组、模型组、假手术组,动态观察各组 裸鼠骨转移癌的生长情况, 测量骨转移癌体积, 绘制生长曲线; 给药20 d 后处死动物, 测取瘤质量, 计算抑瘤率; ELISA 法检测裸鼠血清中相关调节因子PTHrP、RANKL、OPG 含量的变化。结果1.阳和汤高、低剂量组、唑来磷酸组的 骨转移癌灶体积均小于模型组,差异有统计学意义（P＜0.05）;2.阳和汤高、低剂量组、唑来磷酸组PTHrP 和RANKL 含 量明显低于模型组,差异有统计学意义（P＜0.05）,而OPG 含量水平增加,RANKL/OPG 的比率下降,差异有统计学意义 （P＜0.05）。结论1.阳和汤有抗移植性人乳腺癌骨转移作用;2.阳和汤下调PTHrP、RANKL 的含量、增加OPG 的含量, 抑制RANKL/OPG 比率可能是其抑制乳腺癌骨转移的作用机制之一。     

多种含硒复合物对犬乳腺癌细胞CTM1211的抑制作用及其机制

研究不同剂量、形式、配伍的含硒复合物对犬乳腺癌细胞CTM1211的影响,以探究硒抗癌的有效剂量、形式和机制。用低、中、高剂量的CTX(环磷酰胺,1、2、4mg/mL)、SSE(亚硒酸钠,10、20、40μmol/L)、MSA(甲亚硒酸,10、20、40μmol/L)、MSC(硒代半胱氨酸,200、400、800μmol/L)、CTX+SSE(0.5 mg/mL+5μmol/L、1mg/mL+10μmol/L、2mg/mL+20μmol/L)、CTX+MSA(0.5mg/mL+5μmol/L、1mg/mL+10μmol/L、2mg/mL+20μmol/L)、CTX+MSC(0.5mg/mL+100μmol/L、1mg/mL+200μmol/L、2mg/mL+400μmol/L)分别作用CTM1211细胞24、48、72h,MTT法检测以上各组细胞存活率;用CTX(2 mg/mL)、SSE(40μmol/L)、MSA(20μmol/L)、MSC(400μmol/L)、CTX+MSA(2 mg/mL+20μmol/L)分别作用CTM1211细胞48h,流式细胞仪检测各组细胞凋亡率,免疫组化法及RT-qPCR法分别检测VEGF-a(血管内皮生长因子a)、PTEN(磷酸酯酶与张力蛋白同源物)、Ang-2(血管生成素2)、HIF-1a(缺氧诱导因子1a)蛋白和mRNA的表达。与对照组比较,各硒作用组的细胞存活率在48h/72h时显著降低(P0.01或P0.05)、凋亡率显著增高(P0.01),其中CTX+MSA组效果最显著;VEGF-a、Ang-2和HIF-1a蛋白及mRNA的表达在整体上被显著下调,PTEN蛋白及mRNA的表达在整体上被显著上调。结果表明,硒尤其是MSA能显著抑制犬乳腺癌细胞CTM1211,其作用机制与诱导凋亡和调节肿瘤血管生长相关因子VEGF-a、PTEN、Ang-2、HIF-1a有关。     

局部晚期乳癌术前动脉灌注化疗与非化疗的术后疗效比较

比较局晚期乳癌术前动脉灌注化疗与非化疗的术后疗效。方法经病理确诊的按国际抗癌联盟标准ＴＮＭ分期的ⅢＡ、ⅢＢ期乳癌４８例,分为试验组３３例,对照组３５例。结果试验组术前动脉灌注化疗总有效率４７．７％,术后３ａ,５ａ生存率比对照组分别提高３９．０％和２９．０％,两组术后疗效比较差异有显著性。     

转染抑癌基因PTEN对人乳腺癌ZR-75-1细胞的细胞周期和增殖能力的影响

目的：观察PTEN（phosphatase and tensin homology deleted on chromosome ten，第10号染色体上磷酸酶和张力蛋白同源缺失的基因）对人乳腺癌细胞ZR-75-1细胞增殖和细胞周期的影响。方法；利用脂质体介导法将携带有野生型和突变型PTEN cDNA的真核表达载体pBP—wt—PTEN和pBP—G129R—PTEN导八人乳腺癌ZR-75-1细胞（质粒转染成功后实验分为C—WT—PTEN组、CG129R—PTEN组和未转染质粒组即对照组）后，以RT—PCR、Western blot分析目的基因的表达，并采用MTT法和流式细胞术检测细胞增殖和细胞周期。结果：C—WT—PTEN组、C—G129R—PTEN组细胞PTEN mRNA及PTEN蛋白出现明显的高表达。C—WT—PTEN组细胞生长的抑制率可高达42．7％，与对照组比较．差异有显著性（P〈0．05）。但C—G129R—PTEN组细胞生长的抑制率与对照组比较，差异无显著性（P〉0．05）。流式细胞术显示C—WT—PTEN组细胞周期从G1期到S期已发生抑制。结论：野生型PTEN可依赖其磷酸酶活性抑制肿瘤细胞的增殖,并最终诱导细胞凋亡。     

黄芩苷对人结肠癌HCT-116细胞增殖和凋亡的影响

目的 观察黄芩苷对人结肠癌HCT-116细胞增殖和凋亡的影响.方法 用不同浓度黄芩苷(6.25、12.5、25、50、100、200 μmol/L)处理HCT-116细胞,分别用MTT、流式细胞术、实时荧光定量PCR观察细胞增殖、凋亡及Caspase-3、Survivin表达.结果 黄芩苷以剂量、时间依赖方式抑制HCT-116细胞增殖、促进细胞凋亡(P＜0.01或0.05).Caspase-3表达随黄芩苷浓度增高而上调,而Survivin表达下调.结论 黄芩苷可能通过调控Caspase-3、Survivin表达,抑制HCT-116细胞增殖并诱导凋亡.