1α,25（OH）2D3通过阻滞细胞周期抑制胃癌细胞系增殖简

 目的 研究1α,25(OH) 2D3对胃癌细胞增殖和细胞周期的影响,并探讨其相关的作用机制。方法 BGC-823和SGC-7901胃癌细胞株分别给予终浓度为10-10~10-7mol/L的1α,25(OH) 2D3处理72h,用MTT法检测细胞抑制率;用流式细胞仪检测细胞周期;用RT-qPCR技术检测细胞周期相关基因P21、cyclinD1、cyclinE1和CDK6 mRNA表达。 结果1α,25(OH) 2D3对胃癌细胞的增殖抑制率具有浓度依赖性, 1α,25(OH) 2D3干预导致BGC-823和SGC-7901细胞株G1期细胞比例升高,S期细胞比例降低 (P<0.05); 1α,25(OH) 2D3干预后,BGC-823和SGC-7901胃癌细胞P21 mRNA表达升高(P<0.01),而cyclinD1、cyclinE1和CDK6 mRNA表达降低(P<0.01)。结论 1α,25(OH) 2D3抑制胃癌细胞增殖,诱导细胞周期阻滞,可能与上调P21,下调cyclinD1、cyclinE1和CDK6的表达有关。     

小分子化合物P-275抑制胃癌细胞增殖及机制研究

目的研究小分子化合物P-275对人胃癌细胞BGC823、SGC7901、MKN-45增殖的抑制作用及其机制。方法分别用不同浓度的化合物P-275处理人胃癌细胞BGC823、SGC7901和MKN-45,MTT法检测化合物对细胞增殖的影响,流式细胞术检测化合物对细胞周期的影响,Western Blot检测化合物对周期调控蛋白Cyclin D1、CDK4表达的影响。结果化合物P-275能够以剂量依赖的方式抑制人胃癌细胞BGC823、SGC7901及MKN-45的增殖,同时能够抑制上述细胞G1期向S期的转化。Western Blot结果显示P-275能够以剂量依赖的方式下调胃癌细胞SGC7901中周期调控蛋白Cyclin D1、CDK4的表达。结论化合物P-275能够通过下调胃癌细胞中周期调控蛋白Cyclin D1、CDK4的表达,从而抑制胃癌细胞G1期向S期的转化,进而抑制胃癌细胞的增殖。     

小分子化合物H-131抑制胃癌细胞增殖及机制

目的研究小分子化合物H-131对人胃癌细胞SGC7901、BGC823、MKN-45增殖的抑制作用及其相关机制。方法应用不同浓度的化合物H-131处理人胃癌细胞SGC7901、BGC823和MKN-45,采用MTT法检测该化合物对细胞增殖的影响,流式细胞术检测其对细胞周期的影响,Westernblot检测化合物对周期调控蛋白CyclinD1和CDK4表达的影响。结果化合物H-131能够以剂量依赖的方式抑制人胃癌细胞SGC7901、BGC823及MKN-45的增殖,并且能够抑制上述细胞G_1期向S期的转化。Westernblot结果显示H-131能够以剂量依赖的方式下调胃癌细胞SGC7901中CyclinD1和CDK4的蛋白表达水平。结论化合物H-131能够通过下调胃癌细胞中CyclinD1和CDK4的表达水平,抑制胃癌细胞G_1期向S期的转化,进而抑制胃癌细胞增殖。     

Bmi-1 基因过表达对人正常胃黏膜上皮细胞株GES-1增殖的影响

目的: 探讨原癌基因B淋巴瘤莫洛尼鼠白血病病毒插入区1( Bmi-1 )过表达对人正常胃黏膜上皮细胞株GES-1增殖的影响。方法: 采用逆转录病毒介导转染方法将携带原癌基因 Bmi-1 的质粒或空质粒稳定转染GES-1细胞,通过real-time PCR及Western blotting在mRNA及蛋白水平鉴定转染效果。流式细胞术检测过表达 Bmi-1 对GES-1细胞周期的影响。应用CCK-8(Cell Counting Kit-8)试剂盒检测稳定转染 Bmi-1 对GES-1细胞增殖的影响。结果: Real-time PCR及Western blotting结果均表明成功建立稳定转染 Bmi-1 基因的GES-1细胞株。流式细胞术结果表明,过表达 Bmi-1 基因使GES-1细胞G₀/G₁期减少,G₂/M期和S期细胞增多。生长曲线显示,过表达 Bmi-1 基因使GES-1细胞增殖速度明显提高。结论: 过表达 Bmi-1 基因能调控GES-1细胞的细胞周期,促进GES-1细胞的增殖。     

9-顺式维甲酸对甲状腺鳞癌细胞周期及CyclinD1、CDK4表达的影响

 摘 要：目的 探讨9-顺式维甲酸（9-cisRA）对甲状腺鳞癌细胞株SW579细胞周期及周期因子表达的影响。方法以终浓度分别为为10-7 mol/L、10-6 mol/L、5×10-6 mol/L、10-5 mol/L 的9-cisRA处理SW579细胞株，采用MTT比色法测定细胞增殖活性；流式细胞仪检测细胞周期；用RT-PCR方法检测SW579细胞CDK4、CyclinD1mRNA的表达水平；用Western blotting检测SW579细胞CDK4、CyclinD1的蛋白表达。结果 9-cisRA作用后，MTT结果显示，各组细胞均出现显著的生长抑制作用，生长抑制率明显升高，并呈剂量依赖性。流式细胞仪分析，各组细胞均随着药物浓度的升高，S期细胞在细胞周期中所占比例逐渐减少，G1期细胞则明显增加（P<0.01）,细胞滞留在G1期。RT-PCR检测结果表明，经不同浓度9-cisRA处理的细胞CDK4 mRNA表达水平没有明显变化；CyclinD1的表达水平明显下调；Western blotting检测结果表明经不同浓度9-cisRA处理的细胞CDK4蛋白表达水平没有明显变化，CyclinD1蛋白表达水平明显下降。结论9-cisRA对SW579细胞有显著的生长抑制作用，可能与抑制CyclinD1的表达，从而将细胞阻滞于G1期有关。     

BMP-4 and Noggin signaling modulate dorsal fin and somite development in the axolotl trunk.

BMP-4, a member of the TGF-beta superfamily of growth factors, is involved in various developmental processes. We investigated the effects of BMP-4 and its antagonist Noggin on axolotl trunk development. Implantation of BMP-4-coated microbeads caused inhibition of muscle and dorsal fin formation in the vicinity of the microbeads. At some distance, myotomes developed with reduced height but increased width, which was accompanied by increased cell proliferation. These effects could be modulated by co-implanting Noggin-coated beads. Immunostaining of Pax7 further revealed that although the dermomyotome was absent in the vicinity of BMP-4-coated beads, at some distance from them, it was thicker than in controls, indicating that moderate amounts of BMP-4 stimulate this layer of undifferentiated cells. In contrast, Noggin generally inhibited the dermomyotome, possibly indicating premature differentiation of dermomyotome cells. We conclude that BMP-4 and Noggin are involved in the regulation of cell proliferation and differentiation during somite development.     

CDK1 siRNA干扰在Taxol诱导细胞凋亡中的作用

目的 研究转染细胞周期依赖性蛋白激酶1(cyclin-dependent kinase 1,CDK1)siRNA、以及转染后进行凋亡刺激对细胞周期和凋亡的影响,探讨CDK1在细胞凋亡中的确切作用,揭示细胞周期与细胞凋亡协调的分子机制.方法 以人宫颈癌细胞株HeLa细胞为研究对象,脂质体转染CDK1 siRNA,转染后48 h加紫杉醇(Taxol) (20 μg/ml)刺激凋亡,Western印迹检测CDK1和抗凋亡蛋白BCL2表达,AnnexinV/PI法检测细胞的凋亡,流式细胞仪分析DNA含量检测细胞周期.结果 转染CDK1 siRNA后,CDK1蛋白的表达下降,细胞周期G2/M期比例增加,细胞凋亡率与对照相比没有明显升高.只加Taxol刺激12 h后细胞凋亡率增加并伴有S期和G2/M期比例增加. 转染CDK1 siRNA后再用Taxol刺激,其细胞凋亡率没有明显改变,G2/M期阻滞效应也没有叠加.BCL2蛋白只在加Taxol刺激组表达下降,与CDK1表达减少没有相关性.结论 siRNA沉默导致的CDK1表达降低只导致细胞周期G2/M期阻滞,没有引起细胞凋亡;CDK1的表达降低对紫杉醇所诱导的细胞周期阻滞和细胞凋亡效应没有明显影响.     

Icariin stimulates MC3T3-E1 cell proliferation and differentiation through up-regulation of bone morphogenetic protein-2

Previous studies suggest that icariin has anabolic effects on bone, but the mechanisms are unknown. We aimed to investigate the osteogenic effects of icariin in an undifferentiated osteoblast cell line by detecting cell morphology, viability, cell cycling and bone morphogenetic protein-2 (BMP-2) expression. We treated pre-osteoblastic MC3T3-E1 cells with different concentrations of icariin [0 (as a control), 10, 20 and 40 ng/ml] for 48, 72 and 96 h. Cell morphology, viability and the cell cycle were examined and measured using microscopy, the MTT assay or flow cytometry, respectively. BMP-2-positive cells and BMP-2 protein expression levels in icariin-treated MC3T3-E1 cells were examined using immunohistochemistry staining with fluorescence optical density analysis and Western blotting. MC3T3-E1 cells showed typical characteristics of osteoblasts in response to treatment with icariin. Cells treated with all concentrations of icariin had increased percentages of S-phase cells and decreased percentages of G1-phase cells, especially in the 10 and 20 ng/ml icariin groups. The number of BMP-2-positive cells and BMP-2 protein expression levels in the 10 and 20 ng/ml icariin treatment groups were greater compared to the 0 and 40 ng/ml groups. Treatment of icariin promotes osteoblast MC3T3-E1 proliferation and differentiation in vitro, potentially owing to its role in increasing BMP-2 protein expression. Icariin potentially can be used as a drug in clinical settings to treat osteoporosis.     

抑制cyclinD1表达对乳腺癌细胞增殖及cyclinE、CDK2和p21cip1转录的影响

目的　分析探讨人乳腺癌细胞中 cyclin D1的表达受到反义 RNA抑制后 ,细胞增殖能力的变化以及cyclin E,CDK2和 p2 1cip1 (cip1/ waf1/ sdi1)基因表达受到的影响。　方法　将表达 cyclin D1反义 RNA的重组质粒转入人乳腺癌细胞 ,由此抑制细胞中 cyclin D1的表达 ,然后分析细胞生长速率和各时相细胞分布比例的变化 ,并通过Northern blot分析有关基因的表达水平。　结果　 cyclin D1表达受到抑制的细胞与对照相比 ,细胞增殖速率明显下降 ,培养至第 6 d时 ,生长抑制率为 5 4%。细胞周期各时相的分布比例也有较大的变化 ,G1期细胞比例上升 ,而 S期及 G2 / M期细胞比例下降。cyclin E和 CDK2的 m RNA水平显示出有不同程度的下降 ,而 p2 1cip1的表达无明显变化。　结论　 cyclin D1表达的抑制可明显减弱人乳腺癌细胞的异常增殖 ,同时表明同为细胞周期调控基因的 cyclin E和CDK2的表达与 cyclin D1的表达密切相关 ,而 p2 1cip1的表达不受 cyclin D1的影响     

尾叶香茶菜二萜类化合物B对小鼠前列腺癌细胞细胞周期的影响及其机制

目的：观察尾叶香茶菜二萜类化合物B(DB)对小鼠前列腺癌细胞株RM-1细胞周期的影响并分析其机制。方法：MTT法观察不同时间、不同剂量的DB对RM-1 细胞增殖率的影响；相差显微镜观察对RM-1细胞形态影响；流式细胞术分析细胞周期变化；RT-PCR和Western blotting分别观察DB作用后RM-1细胞p53、GRIM-19、STAT3 和细胞周期相关因子CHK1、CDK2 mRNA和蛋白水平的表达。结果：（1）MTT结果：DB可抑制RM-1 细胞的增殖，呈时间、剂量依赖性；（2）形态学观察和流式细胞术检测：经DB处理后的RM-1细胞出现生长抑制，细胞主要阻滞在G1期；（3）RT-PCR结果： DB (2 mg/L,4 mg/L,8 mg/L) 分别作用RM-1细胞12 h、24 h、48 h后，p53、CHK1、GRIM-19 mRNA的含量明显高于对照组，CDK2、STAT3 mRNA的含量明显低于对照组（P<0.05）；（4）Western blotting 结果：DB (2 mg/L,4 mg/L,8 mg/L) 分别作用RM-1细胞12 h、24 h、48 h后，P53、GRIM-19 蛋白表达水平高于对照组，而CDK2蛋白表达水平则低于对照组。结论：DB可抑制RM-1细胞增殖，其机制可能是与细胞周期相关基因p53的上调，CDK2表达下降有关，影响了G1期进入S期，同时GRIM-19-STAT3-CDK2途径可能也参与G1期阻滞的过程。     

Benznidazole modulates cell proliferation in acute leukemia cells

Abstract

Context: We have previously reported that benznidazole (BZL), known for its trypanocidal action, has anti-proliferative activity against different cell lines like HeLa and Raw 264.7 among others. At the moment, it has not been reported if the anti-proliferative effect of BZL is similar for non-adherent hematopoietic cells like was reported for adherent cancer cell lines.

Objective: We aimed to investigate the efficacy of BZL on the growth of the leukemic cell lines THP-1 and OCI/AML3.

Materials and methods: We evaluated cell proliferation by [³H]-thymidine incorporation and MTT reduction as well as cell death by lactate dehydrogenase (LDH) activity. We assessed apoptosis by flow cytometry for detection of annexin V-positive and propidium iodide-negative cells, along with nuclear morphology by diamidino-2-phenolindole (DAPI) staining. Western blot studies were performed to evaluate changes in cell cycle proteins in BZL-treated cells.

Results: BZL significantly reduced proliferation of both cell lines without inducing cell death. Likewise it produced no significant differences in apoptosis between treated cells and controls. In addition, flow cytometry analysis indicated that BZL caused a larger number of THP-1 cells in G0/G1 phase and a smaller number of cells in S phase than controls. This was accompanied with an increase in the expression of the CDK inhibitor p27 and of cyclin D1, with no significant differences in the protein levels of CDK1, CDK2, CDK4, cyclins E, A and B as compared to controls.

Conclusion: BZL inhibits the proliferation of leukemic non-adherent cells by controlling cell cycle at G0/G1 cell phase through up-regulation of p27.     

TGF-β1对胃癌细胞增殖、凋亡及miR-302a和AKT通路的影响

目的探究转化生长因子-β1(TGF-β1)对胃癌细胞增殖、凋亡及miR-302a和AKT通路的影响.方法在含有TGF-β1(0、1、5、10 ng/ml)的培养基培养胃癌细胞系BGC-823,MTT法检测细胞增殖情况;平板克隆形成实验检测细胞克隆形成数量;Hoechst33258染色观察细胞形态;流式细胞术检测细胞凋亡以及周期阻滞情况;实时荧光定量PCR(qRT-PCR)检测细胞miR-302a表达;蛋白印迹(WB)法检测p-PI3K、AKT、p-AKT蛋白表达情况.结果与Control组相比,TGF-β1处理组细胞增殖抑制率、细胞凋亡率升高,细胞克隆数量降低,且随着TGF-β1浓度的增加,细胞增殖抑制率、细胞凋亡率逐渐升高,细胞克隆数量逐渐降低(P<0.05).与Control组相比,TGF-β1处理组G1期细胞比例显著增加,G2期细胞比例显著降低,且随着TGF-β1浓度的增加,G1期细胞比例逐渐增加,G2期细胞比例逐渐降低(P<0.05).与Control组相比,TGF-β1处理组miR-302a表达升高,p-PI3K、p-AKT蛋白表达水平均显著降低,且随着TGF-β1浓度的增加,miR-302a表达逐渐升高,p-PI3K、p-AKT蛋白表达逐渐降低(P<0.05).结论TGF-β1可能通过上调miR-302a表达、抑制AKT通路,使细胞G1期阻滞,从而抑制胃癌细胞增殖,促进其凋亡.     

Bone morphogenetic protein-2 induces hypophosphorylation of Rb protein and repression of E2F in androgen-treated LNCaP human prostate cancer cells

Bone morphogenetic protein-2 (BMP-2), a multifunctional member of the transforming growth factor (TGF)-beta, superfamily, has powerful osteoinductive effects and causes cell cycle arrest in a variety of transformed cell lines. We have observed BMP-2-induced inhibition of cell proliferation in an androgen-dependent human prostate cancer cell line (LNCaP). To investigate the mechanism of inhibition of androgen-dependent growth by BMP-2, we examined the effect of dihydrotestosterone (DHT) and/or BMP-2 on cell cycle-related proteins in LNCaP cells. BMP-2 decreased the phosphorylation of retinoblastoma (Rb) protein induced by treatment with DHT. DHT-induced expression of cyclin A and cyclin-dependent kinase 2 (CDK2) protein was also inhibited by co-treatment with BMP-2. Furthermore, BMP-2 induced expression of p21(WAF1/CIP1), a CDK inhibitor. These results indicate that changes in expression of these proteins lead to modulation of the phosphorylation state of Rb. DHT-induced E2F-1 protein and mRNA expressions was also inhibited by BMP-2, suggesting that BMP-2 inhibits DHT-induced growth of LNCaP cells through a decrease in E2F protein expression and suppression of E2F activity by hypophosphorylation of Rb.     

氯喹对人肺癌A549细胞周期阻滞及增殖抑制的机制

目的 探讨氯喹抑制人非小细胞肺癌A549细胞增殖、促进凋亡、阻滞细胞周期的作用及其分子机制。 方法 应用MTT法和流式细胞术分别检测氯喹对A549细胞增殖、细胞凋亡和细胞周期的影响;Western blotting检测氯喹对A549细胞周期蛋白(cyclin E1)和细胞周期蛋白依赖性激酶（CDK2）、肿瘤抑制蛋白PTEN以及细胞周期抑制蛋白P21、P27表达水平的影响。 结果 氯喹能够抑制A549细胞增殖,并且具有时间-剂量依赖性。氯喹可以诱导细胞凋亡,不同浓度的氯喹作用于A549细胞24h后,细胞凋亡率随着作用剂量的增加而升高。进一步的研究发现,氯喹还能够阻滞细胞周期于G₀/G₁期,降低cyclinE1和CDK2表达水平,明显提高PTEN、P21和P27的表达水平。 结论 氯喹具有抑制肺癌细胞增殖、促进其凋亡和阻滞细胞周期的作用,其机制可能与其抑制CyclinE1和CDK2表达,并且上调PTEN、P21和P27蛋白的表达有关。     

ATF4对皮肤癌细胞增殖的影响及相关机制

目的：探讨沉默/过表达ATF4对人皮肤癌细胞增殖的影响及其相关作用机制。方法：Western blot技术检测不同类型皮肤癌细胞中ATF4的蛋白表达水平。构建ATF4沉默/过表达的A431皮肤癌细胞株,采用CCK-8法、克隆形成实验和流式细胞术检测A431细胞增殖能力的变化及细胞周期分布;Western blot技术检测细胞周期调控因子cyclin D1、cyclin E、P21和p-Rb/Rb的蛋白表达水平。结果：ATF4在3种不同类型的皮肤癌细胞中均呈高表达。CCK-8法和克隆形成实验结果显示沉默ATF4的A431细胞存活率和增殖能力均显著降低(P<0.05),而过表达ATF4可促进A431细胞的增殖;流式细胞仪检测结果显示沉默ATF4可明显抑制A431细胞从G0/G1期向S期转换,过表达ATF4则促进其G1/S转换。同时Western blot实验结果显示沉默ATF4后,cyclin D1、cyclin E和p-Rb的蛋白水平均显著降低,而P21的蛋白表达显著增加(P<0.05),过表达ATF4后则cyclin D1、cyclin E和p-Rb的蛋白水平显著增加,而P21的蛋白表达显著降低(P<0.05)。结论：ATF4能够促进人皮肤鳞状细胞癌细胞株A431的增殖,其潜在作用机制可能与促进细胞周期G1/S转换及影响相关周期调控因子的表达有关,提示AT F 4可作为治疗皮肤癌的一个潜在作用靶点。     

DNMT在胃癌中的表达及DNMT抑制剂5-氮杂-2’-脱氧胞苷对胃癌的影响

目的: 研究DNA甲基化转移酶(DNMT)各亚型DNMT1、DNMT2、DNMT3A、DNMT3B和DNMT3L在胃癌与胃黏膜中的表达特点,并分析DNMT抑制剂5-氮杂-2’-脱氧胞苷对胃癌和胃黏膜细胞的影响。方法: 免疫组化法对60例胃癌与癌旁组织行5种DNMT表达研究。免疫荧光法和Western免疫印迹法对SGC-7901、MKN-45(胃癌细胞)和GES-1(胃黏膜细胞)行5种DNMT表达研究。噻唑蓝比色法和流式细胞术分析5-氮杂-2’-脱氧胞苷对SGC-7901、MKN-45和GES-1增殖、细胞周期和凋亡的影响。结果: 胃癌与癌旁组织均有5种DNMT不同程度表达,但胃癌组织DNMT1和DNMT3A表达显著低于癌旁组织(P<0.01),DNMT2和DNMT3L表达也低于癌旁组织(P<0.05),只有DNMT3B在胃癌与癌旁组织中无显著差异(P>0.05)。胃癌细胞(SGC-7901和MKN-45)与胃黏膜细胞(GES-1)亦有部分DNMT表达,除DNMT3B在胃黏膜细胞表达较强外,余DNMT在胃癌与胃黏膜细胞中无显著差异。5-氮杂-2’-脱氧胞苷对胃癌与胃黏膜细胞的增殖率、周期分布和凋亡率并无显著影响。结论: DNMT在胃癌中表达呈降低趋势,抑制DNMT对胃癌细胞的增殖和凋亡无显著影响。