茶多酚对膀胱癌细胞株T24和SCaBER体外生长抑制的实验研究

目的 研究茶多酚对膀胱癌细胞株生长的抑制作用及其可能的分子机制。方法 采用MTT法和流式细胞术 ,分析膀胱癌细胞株 (T2 4及SCaBER )经不同浓度的的茶多酚作用前后 ,细胞生长抑制率、细胞凋亡率、细胞周期以及细胞PTEN蛋白表达变化的影响。结果 培养液中加入 0、5 0、10 0、2 0 0、40 0 μg·ml-1茶多酚 ,T2 4细胞和SCaBER细胞的生长抑制率分别为 0、11.2 %、3 3 .4%、3 6.9%、67.5 %和 0、16.5 %、19.1%、3 0 .3 %、3 1.4%。流式细胞仪直方图上见亚二倍体峰 ,2株癌细胞均出现凋亡 ,凋亡率分别为 6.8%、2 5 .1%、2 8.6%、3 6.6%、41.1%和 2 1.4%、2 7.2 %、2 8.5 %、3 6.8%、47.7% ;同时 ,随茶多酚作用浓度的提高 ,阻滞于G1期的 2株癌细胞均明显增加 ,细胞分裂增殖指数 (PI)均降低 ;而细胞PTEN蛋白表达水平分别由 ( 3 7.66± 0 .49)、( 3 8.2 8± 0 .61) (TP ,0 μg·ml-1)增加至 ( 163 .92± 3 .3 6)、( 177.3 6± 10 .79) (TP ,40 0 μg·ml-1) (P均 <0 .0 1)。结论 茶多酚对T2 4及SCaBER细胞生长具有抑制作用 ,其机制之一可能是通过上调PTEN蛋白表达阻滞细胞由G1期进入S期和诱导细胞凋亡。TP抑制T2

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。

Inhibition effects of parathyroid hormone on human medullary thyroid carcinoma cells

Objective： The purpose of the study was to investigate the effects of parathyroid hormone and parathyroid hormone receptor monoclonal antibody on in vitro growth and proliferation of human medullary thyroid carcinoma cell lines. Methods： The medullary thyroid carcinoma cell line was cultured in vitro, with parathyroid hormone and parathyroid hormone receptor monoclonal antibody treatment intervention, the growth of the cells was observed under an inverted contrast micro scope, the MTT assay was used to detect the cell growth inhibition rate. Results： Under the inverted contrast microscope, the cells changed significantly, the parathyroid hormone and parathyroid hormone receptor monoclonal antibodies can effectively inhibit the proliferation of medullary thyroid cancer cells in a time and dose dependent. When parathyroid hormone concentra tion reached a concentration of 2.0 IJmol/L, the parathyroid hormone receptor monoclonal antibody reached a concentration of 1.0 μmol/L, the cell growth was most significantly inhibited （P 〈 0.05）. Conclusion： Parathyroid hormone and parathyroid hormone receptor monoclonal antibody were able to inhibit the proliferation of medullary thyroid carcinoma cells and signifi cantly reduce the proliferation index.

The Inhibitory Effect of Oridonin on the Growth of Fifteen Human Cancer Cell Lines

OBJECTIVE To study the inhibitory effect of oridonin on the growth of cancer cells. METHODS Fifteen human cancer cell lines were subjected to various concentrations of oridonin in culture medium. The inhibitory rate of cell growth was measured by the MTT assay, and compared with a negative control and 5-Fu-positive control. RESULTS The 50% inhibiting concentration （IC50） and maximal inhibition （Imax） of oridonin shown by studying the growth of the cancer cell lines were as follows： leukemias （HL60 cells： 3.9 μg/ml and 73.8%, K562 cells： 4.3 μg/ml and 76.2%）; esophageal cancers（SHEEC cells： 15.4 μg/ml and 99.2%, Eca109 cells： 15.1 μg/ml and 84.6%, TEl cells： 4.0 μg/ml and 70.2%）; gastric cancers （BGC823 cells： 7.6 μg/ml and 98.7%, SGC7901 cells： 12.3 μg/ml and 85.7%）; colon cancers （HT29 cells： 13.6 μg/ml and 97.2%, HCT cells： 14.5 μg/ml and 96.5%）; liver cancers （Bel7402 cells： 15.2 μg/ml and 89.2%, HepG2 cells： 7.1 μg/ml and 88.3%）; pancreatic cancer （PC3 cells： 11.3 μg/ml and 68.4%）; lung cancer （A549 cells： 18.6 μg/ml and 98.0% ）; breast cancer （MCF7 cells： 18.4 μg/ml and 84.7%）; uterine cervix cancer （Hela cells： 13.7 μg/ml and 98.5%）. CONCLUSION Oridonin had a relatively wide anti-tumor spectrum, and a relatively strong inhibitory effect on the growth of the 15 human cancer cells. Inhibitory effects were concentration dependent.

Antisense EGFR sequence reverses the growth properties of human liver carcinoma cell line BEL-7404 in vitro

A recombinant plasmid containing a full length human epidermal growth factor receptor (EGFR) cDNA sequence in antisense orientation was transferred into cells of a human liver carcinoma cell line BEL-7404. Compared with the control cell clone JX-0 transferred with the vector plasmid and the parent BEL-7404 cells, the antisense EGFR transferred cell clone JX-1 showed a decreased EGFR gene expression and reduced significantly the growth potential either in anchorage-dependent or anchorage-independent growth. Furthermore. JX-1 cells appeared to be distinctly dependent on serum concentration for monolayer growth. The results suggested that antisense EGFR could partly block the EGFR gene ex-pression and reverse the malignant growth properties of human liver carcinoma cells in vitro.

rmhTNF-α Combined with Cisplatin Inhibits Proliferation of A549 Cell Line In Vitro

Objective To explore the inhibitory effect of recombinant mutant human tumor necrosis factor-α(rmhTNF-α) in combination with cisplatin on human lung adenocarcinoma cell line A549. Methods Human lung adenocarcinoma cell line A549 was treated with varying concentrations of rmhTNF-α(0.38, 0.75, 1.50, 6.00 and 12.00 IU/ml) or cisplatin(3.91, 7.81, 15.63, 31.25 and 62.50 μg/ml) for 24 hours. Viable cell number was analyzed by using crystal violet staining. The inhibitory rates of A549 cells growth by the two drugs were calculated. For analyzing whether there was a synergistic effect of rmhTNF-α with cisplatin, A549 cells were treated with 0.75 IU/ml rmhTNF-α and increased concentrations of cisplatin. Results rmhTNF-α or cisplatin inhibited the growth of A549 cell lines in a dose-dependent manner. The inhibitory effect of rmhTNF-α combined with cisplatin was significantly greater than cisplatin alone at the same concentration(all P<0.01). Conclusion rmhTNF-α combined with cisplatin might have synergistic inhibitory effect on human lung adenocarcinoma cell line A549.

The use of suicide gene systems in vascular cells in vitro

To investigate the efficiency of suicide gene systems on vascular cells, HSV-tk/GCV and EC-CD/5-FC systems were established on vascular endothelial cells in vitro by retroviral transduction. Both modified cell lines were highly sensitive to prodrugs, the IC50 for GCV was less than 0.4 μM, and IC50 for 5-FC was less than 75 μM,while the parental endothelial cells were insensitive even at the highest concentrations of prodrugs in this experiment. Mixed cellular assay showed that significant bystander effect was exhibited in modified endothelial cells.When only 10% or 30% of the mixed cells were tk positive and exposed to 20 μM GCV for 6 days, more than 60% or 90% of the whole population was killed. Similar result was also found in CD positive cells. These results indicated that both HSV-tk/GCV and EC-CD/5-FC systems could efficiently suppress endothelial cell growth in vitro.

In Vitro Hyphal Growth Inhibition of Plant Pathogenic Fungi by Corrigiola Telephiifolia Extracts

The sugar beet root rot and Bayoud disease, respectively caused by Sclerotium rolfsii and Fusarium oxysporum albedinis, are major agricultural problems in Morocco, affecting its economical and social conditions. As of now, no effective control method of these phytopathogens is available. Therefore the search for new efficient and ecologically undamaging fungicides was essential. The present study reports the antifungal activity of five organic extracts of Corrigiola telephiifolia Pourr., a Moroccan medicinal plant, against these fungi using mycelial growth inhibition assays （in vitro）. The extracts concentration varied from 0.01 to 1 mg.mlt. Also, preliminary information on the chemical composition of the extracts is included. The results showed a difference in sensitivity of both fungi toward the plant extracts. The mycelia growth of Sclerotium rolfsii was concentration and time-dependant. It was markedly inhibited by the polar extracts especially at high dose （p〈 0.001）. While Fusarium oxysporum f. sp. albedinis was much less sensitive.