CIK细胞对乳腺癌细胞株ZK-75-1的杀伤作用及其机制

目的：研究多种细胞因子诱导的杀伤细胞（cytokine-induced killing cells,CIK）对乳腺癌细胞株ZK-75-1的杀伤作用,并探讨其作用机制.方法：通过HE染色观察凋亡细胞ZK-75-1的形态学改变.应用TUNEL（TdT-mediated dUTPnick end labeling）法检测CIK细胞的凋亡.通过免疫细胞化学染色法检测ZK-75-1细胞中p53、p16、C-myc、Bcl-2及Bax的表达率.结果：HE染色显示,CIK细胞向ZK-75-1细胞靠近,形成典型的玫瑰花环状;肿瘤细胞的胞浆中出现颗粒状物,有的肿瘤细胞只见颗粒状碎片;而作为对照的乳腺癌细胞生长良好.TUNEL法检测显示,对照组细胞未染色或染呈均匀的淡蓝色;实验组凋亡的细胞缩小,核或核周染呈深蓝色.CIK细胞作用4～12 h ZK-75-1细胞的凋亡率上升,作用12～24h细胞的凋亡率下降,与对照组相比较有统计学意义（P＜0.01）.免疫细胞化学染色的结果表明,CIK细胞实验组p53、pi6、C-myc及Bcl-2蛋白随作用时间的延长均下降,Bax蛋白的表达上调,与对照组相比较均有统计学意义（P＜0.01）.结论：CIK细胞对乳腺癌细胞ZK-75-1杀伤作用的机制之一,可能与p53、p16、C-myc、Bcl-2蛋白表达的下调及Bax蛋白表达的上调有关,并与CIK细胞作用的时间关系密切.

Angiotensin-(1-7)Changes Apoptosis-Related Genes Expression in Human Breast Cancer Cell Line T47D

Angiotensin-(1-7) [Ang-(1-7)] is a heptapeptide of the renin-angiotensin system with vasodilator and anti-proliferative properties. In the present study, we aim to investigate whether Ang-(1-7) induces apoptosis in breast cancer cells and whether the altered expression of apoptosis-related genes is involved in this process. Human breast cell line T47D was treated with angiotensin-(1-7) and angiotensin II (Ang II). Cell proliferation and apoptosis were quantified using hemocytometer and flow cytometry, respectively. The expression of 84 apoptosis-related genes was evaluated through qPCR array. Ang-(1-7), as opposed to Ang II, decreased proliferation and increased apoptosis in T47D cells. Moreover, many pro-apoptotic genes were up-regulated, such as BAK1, BAX, BCL2L1, BID and BIK. In addition, some anti-apoptotic genes as AKT1 and XIAP were down-regulated by heptapeptide. Although a deeper study should be performed, our results support the hypothesis that Ang-(1-7) could change the expression of several genes related to apoptosis, interfering directly in the molecular pathways associated with the survival of breast cancer cells.

Angiotensin-(1-7)and Human Chorionic Gonadotropin(hCG)Modulate the Nuclear Transcription Factors or Nuclear Receptors Genes in the Tumorigenic Undifferentiated Breast Cancer Cell Line SKBR3

Breast cancer is the most common cancer among women. Angiotensin-(1 - 7) [Ang-(1 - 7)] has been correlated with cancer antiproliferative and apoptotic effects, similar properties of the human Chorionic Gonadotrofin (hCG). The aims of this work are to evaluate the role of Ang-(1 - 7) and of hCG in modulating the expression of Nuclear Receptors and Coregulators related genes in the tumorigenic breast cell line SK-BR3. Three experimental groups were created: control, hCG and hCG + Ang-(1 - 7). Cells were treated for 11 days and then had their RNA extracted. Samples were loaded into PCR Array plates containing 84 genes relate to Nuclear Receptors and Coregulators pathways. Gene expression data were used to construct canonical pathways (MetacoreTM). hCG and hCG + Ang-(1 - 7) treatments markedly modulate the expression of Nuclear Receptors and Coregulators related genes. hCG differentially expressed 17% of the genes, being 29% upregulated and 71% downregulated. Meanwhile, hCG + Ang-(1 - 7) changed the expression of 30% of the genes on the plate, among these genes 56% were upregulated and 44% downregulated. Among these differentially expressed genes, we highlight Esr1, Nr2f2, and Nr2f1, Esr1, Hdac5, and Nr4A1 (>4 fold). Finally MetaCore analysis based on Gene Ontology (GO) generated six networks for hCG and ten networks for the combined treatment. All generated networks are related to regulation of apoptosis or to Programmed Cell Death processes. In summary, our results herein demonstrate that the modulation of sexual hormones and of other nuclear factor genes expression might underlie the tumorigenic protection effect and the induction of cell differentiation caused by the hormones hCG and Ang-(1 - 7), especially in Cancer Stem Cells.

PTEN磷酸酶活性对乳腺癌细胞ZR-75-1迁移能力的影响

目的:探求PTEN蛋白的磷酸酶活性对乳腺癌细胞ZR-75-1转移能力的影响。方法:采用脂质体介导法分别将野生型PTEN质粒(wt-PTEN)、磷酸酶失活的PTEN质粒(G129R-PTEN)和只具有蛋白磷酸酶活性的PTEN质粒(G129E-PTEN)转染PTEN基因缺失的人乳腺癌细胞株ZR-75-1,Western印迹法检测PTEN蛋白及P397-FAK的表达水平,体外细胞划痕实验观察PTEN磷酸酶活性对ZR-75-1细胞迁移能力的影响,细胞基质黏附试验和人工重组基底膜侵袭试验测定PTEN质粒转染和未转染的ZR-75-1细胞的黏附抑制率和侵袭抑制率,免疫组化法检测MMP-2的水平。结果:wt-PTEN、G129R-PTEN及G129E-PTEN3种质粒均成功转染ZR-75-1细胞并有PTEN蛋白的表达,其中wt-PTEN、G129E-PTEN均能抑制ZR-75-1细胞迁移;wt-PTEN和G129E-PTEN转染细胞之间的黏附抑制率和侵袭抑制率或侵袭细胞相对数均无显著性差异,但与G129R-PTEN转染的和未经转染的ZR-75-1细胞相比有显著性差异(P<0.01)。wt-PTEN和G129E-PTEN质粒转染的ZR-75-1细胞其P397-FAK水平均显著低于G129R-PTEN质粒转染的ZR-75-1细胞;wt-PTEN与G129E-PTEN质粒转染的ZR-75-1细胞MMP-2水平对比于G129R-PTEN质粒转染的和未经质粒转染的ZR-75-1细胞有显著性差异(P<0.01)。结论:具有双特异磷酸酶活性的野生型PTEN基因和只具蛋白磷酸酶活性的PTEN基因均能抑制乳腺癌细胞ZR-75-1的迁移,而磷酸酶失活的PTEN基因则无此作用。

抑癌基因PTEN抑制乳腺癌ZR-75-1细胞转移作用机制的探讨

目的探讨抑癌基因PTEN抑制乳腺癌细胞ZR-75-1转移的作用机制。方法用脂质体介导法分别将野生型PTEN质粒(wt)、磷酸酶活性缺失的PTEN质粒(G129R)和只具蛋白磷酸酶活性的PTEN质粒(G129E)转染PTEN基因缺失的乳腺癌细胞ZR-75-1。转染细胞以嘌呤霉素筛选后,用PCR和Western-blot分别检测PTEN基因及其蛋白;通过黏附、侵袭实验,比较3种质粒转染细胞和未转染细胞之间的黏附、侵袭能力的差异;用Western-blot法检测各组转染细胞总的黏着斑激酶(FAK)和磷酸化黏着斑激酶(P397-FAK)的表达水平;以免疫组化法检测基质金属蛋白酶-2(MMP-2)和E-钙连素(E-Cd)的表达,并用RT-PCR检测各组转染细胞的p53 mRNA水平。结果3种质粒均成功转染ZR-75-1细胞,并证实3种转染细胞内均有PTEN基因存在及PTEN蛋白表达;wt、G129R、G129E等3种质粒转染的细胞黏附抑制率分别为65.7%、8.8%和43.5%;侵袭抑制率分别为70.4%、6.9%和63.5%。将wt或G129E转染细胞的黏附抑制率及侵袭抑制率与G129R转染细胞的比较,均有显著性差异(P<0.05);但wt与G129E转染细胞比较,均无显著性差异(P>0.05)。3种转染细胞总FAK水平虽无显著性差异(P>0.05),但wt和G129E转染细胞其P397-FAK和MMP-2水平都显著低于G129R转染细胞(P<0.05)。3种转染细胞间的E-Cd水平未见显著差异。RT-PCR分析显示,wt、G129E和G129R3种转染细胞p53 mRNA水平无显著性差异,但均显著高于未转染细胞。结论野生型PTEN基因所表达的蛋白具脂质和蛋白双特异磷酸酶活性,对乳腺癌细胞ZR-75-1的转移具有抑制作用,其机制与磷酸酶活性有关,其中蛋白磷酸酶活性可能起主要作用。

MiR-142-3p enhances chemosensitivity of breast cancer cells and inhibits autophagy by targeting HMGB1

MiR-142-3p has been reported to act as a tumor suppressor in breast cancer.However,the regulatory effect of miR-142-3p on drug resistance of breast cancer cells and its underlying mechanism remain unknown.Here,we found that miR-142-3p was significantly downregulated in the doxorubicin(DOX)-resistant MCF-7 cell line(MCF-7/DOX).MiR-142-3p overexpression increased DOX sensitivity and enhanced DOXinduced apoptosis in breast cancer cells.High-mobility group box 1(HMGB1)is a direct functional target of miR-142-3p in breast cancer cells and miR-142-3p negatively regulated HMGB1 expression.Moreover,overexpres sion of HMGB1 dramatically reversed the promotion of apoptosis and inhibition of autophagy mediated by miR-142-3p up-regulation.In conclusion,miR-142-3p overexpression may inhibit autophagy and promote the drug sensitivity of breast cancer cells to DOX by targeting HMGB 1.The miR-142-3 p/HMGB1 axis might be a novel target to regulate the drug resistance of breast cancer patients.

CIK细胞对乳腺癌细胞株抗增殖及诱导凋亡的作用

目的研究多种细胞因子诱导的杀伤细胞(Cytokine-inducedkillcells,CIK)对ZK-75-1乳腺癌细胞株的抗增殖和诱导凋亡作用,并探讨其作用机制。方法应用MTT法检测CIK细胞对ZK-75-1乳腺癌细胞株的抗增殖作用的影响及细胞毒活性;通过倒置显微镜、HE染色、透射电镜观察凋亡细胞的形态学改变。结果MTT比色法表明随着CIK细胞与乳腺癌细胞效靶比增加及作用时间延长,抑制率明显增强(P<0.01)。CIK细胞作用于乳腺癌细胞24h后,形态学观察乳腺癌细胞发生凋亡或坏死。结论CIK细胞是一种新型高效具有较强杀伤体外乳腺癌细胞的免疫活性细胞。

小分子RNA干扰MTA1基因对乳腺癌MDA-MB-231细胞生物活性及相关蛋白表达的影响

目的:采用短发夹状RNA(short hairpin RNA,shRNA)干扰技术沉默乳腺癌细胞MDA-MB-231中转移相关基因(metastasis-associated gene 1,MTA1)的表达,并观察其对15-脂氧合酶-2(15-lipoxygenase-2,15-LOX-2)、p53及bcl-2表达的影响。方法:将shRNA-MTA1载体质粒稳定转染MDA-MB-231细胞,MTT法检测细胞增殖抑制情况,FCM法检测细胞周期及凋亡情况,RT-PCR和Western印迹法检测MTAl、15-LOX-2、p53及bcl-2 mRNA和蛋白表达情况。结果:shRNA-MTA1能明显降低MTA1基因在MDA-MB-231细胞中的表达量;抑制MDA-MB-231细胞的增殖,诱导其凋亡,并使细胞被阻滞在G1期,与对照组相比,差异有统计学意义(P<0.01)。转染shRNA-MTA1可使MDA-MB-231细胞中15-LOX-2和p53 mRNA及蛋白的表达明显增强(P<0.01),而MTA1和bcl-2 mRNA表达明显减弱(P<0.01)。结论:MTA1基因可抑制乳腺癌MDA-MB-231细胞的增殖,诱导其凋亡,该作用可能与上调细胞中15-LOX-2和p53的表达,下调bcl-2的表达有关。