Synergistic Effects of Exemestane and Aspirin on MCF-7 Human Breast Cancer Cells

Objective: The purpose of this study is to investigate the combined effects of exemestane and aspirin on MCF-7 human breast cancer cells. Methods: Antiproliferative effects of exemestane and aspirin, alone and in combination, on growth of MCF-7 human breast cancer cells were assessed using the MTT assay. Synergistic interaction between the two drugs was evaluated in vitro using the combination index (CI) method. The cell cycle distribution was analyzed by flow cytometry and Western blotting was used to investigate the expression of cyclooxygenase-1, cyclooxygenase-2 and Bcl-2. Results: MTT assays indicated that combination treatment obviously decreased the viability of MCF-7 human breast cancer cells compared to individual drug treatment (CI<1). In addition, the combination of exemestane and aspirin exhibited a synergistic inhibition of cell proliferation, significantly arrested the cell cycle in the G0/G1 phase and produced a stronger inhibitory effect on COX-1 and Bcl-2 expression than control or individual drug treatment. Conclusion: These results indicate that the combination of exemestane and aspirin might become a useful method to the treatment of hormonedependent breast cancer. The combination of the two inhibitors significantly increased the response as compared to single agent treatment, suggesting that combination treatment could become a highly effective approach for breast cancer.     

蟾毒灵联合阿霉素对膀胱癌T24细胞生长的影响及机制

目的:观察蟾毒灵联合阿霉素对膀胱癌T24细胞生长的影响，探讨蟾毒灵联合阿霉素抗肿瘤作用的可能机制。方法:用不同浓度的蟾毒灵和阿霉素分别作用于T24细胞，用MTT法检测细胞增殖抑制率，流式细胞仪检测细胞凋亡率，RT-PCR检测凋亡基因Bax及Bcl-2表达水平，再联合使用两组药物作用T24细胞，检测相关凋亡指标。结果:MTT 结果显示，蟾毒灵与阿霉素联合应用比单独应用阿霉素对T24细胞的增殖抑制率要明显提高，差异有统计学意义(P＜0.05)；流式细胞仪结果显示，当蟾毒灵和阿霉素联合应用T24细胞的凋亡率要明显高于单独应用两种药物，差异有统计学意义(P＜0.05)；RT-PCR结果显示，蟾毒灵联合阿霉素能明显下调凋亡抑制基因Bcl-2的表达，上调促凋亡基因Bax的表达，与单独用药相比差异有统计学意义(P＜0.05)。结论:蟾毒灵联合阿霉素可增敏阿霉素对T24细胞的增殖抑制及诱导细胞凋亡的能力;其抗肿瘤活性的机制可能与影响凋亡基因Bax及Bcl-2的表达有关。     

Triptolide induces Bcl-2 cleavage and mitochondria dependent apoptosis in p53-deficient HL-60 cells

Triptolide, a bioactive component of the Chinese medicinal herb Tripterygium wilfordii Hook F., induces p53-mediated apoptosis in cancer cells. This study demonstrated that triptolide activated an alternative p53-independent apoptotic pathway in HL-60 cells. In the absence of an intact p53 and without changing Bax level, at nM range triptolide induced apoptosis with concomitant DNA fragmentation, S phase cell cycle arrest, mitochondrial cytochrome c release and the activation of caspases. Besides, both caspases 8 and 9 were activated and the simultaneous inhibition of both was required to completely block triptolide's apoptotic effect. Importantly, triptolide induced the appearance of a truncated 23kD Bcl-2 which was inhibited by the general caspase inhibitor Z-VAD-FMK. In the MCF-7 cells that possessed the wild type p53 but lacked caspases 3, triptolide induced cell death with an increase in p53 but Bcl-2 remained unaltered. On the other hand, transfected cells overexpressing the 28kD Bcl-2 became more resistant to triptolide and upon triptolide treatment accumulated in the G(1) instead of S phase. After 36h treatment, triptolide activated JNK pathways, at the same time inactivated the ERK and p38 pathways. However, SP600125, a specific JNK inhibitor, could not inhibit the triptolide-mediated cleavage of caspase 3, indicated that activation of JNK might not be related to the apoptotic effects of triptolide. Our data suggest that in the absence of an intact p53 and without altering Bax level triptolide induces apoptosis activates a positive amplification loop involving caspase-mediated Bcl-2 cleavage/activation, mitochondrial cytochrome c release and further activation of caspases.     

Metformin combined with aspirin significantly inhibit pancreatic cancer cell growth in vitro and in vivo by suppressing anti-apoptotic proteins Mcl-1 and Bcl-2

Metformin and aspirin have been studied extensively as cancer preventive or therapeutic agents. However, the effects of their combination on pancreatic cancer cells have not been investigated. Herein, we evaluated the effects of metformin and aspirin, alone or in combination, on cell viability, migration, and apoptosis as well as the molecular changes in mTOR, STAT3 and apoptotic signaling pathways in PANC-1 and BxPC3 cells. Metformin and aspirin, at relatively low concentrations, demonstrated synergistically inhibitory effects on cell viability. Compared to the untreated control or individual drug, the combination of metformin and aspirin significantly inhibited cell migration and colony formation of both PANC-1 and BxPC-3 cells. Metformin combined with aspirin significantly inhibited the phosphorylation of mTOR and STAT3, and induced apoptosis as measured by caspase-3 and PARP cleavage. Remarkably, metformin combined with aspirin significantly downregulated the anti-apoptotic proteins Mcl-1 and Bcl-2, and upregulated the pro-apoptotic proteins Bim and Puma, as well as interrupted their interactions. The downregulation of Mcl-1 and Bcl-2 was independent of AMPK or STAT3 pathway but partially through mTOR signaling and proteasome degradation. In a PANC-1 xenograft mouse model, we demonstrated that the combination of metformin and aspirin significantly inhibited tumor growth and downregulated the protein expression of Mcl-1 and Bcl-2 in tumors. Taken together, the combination of metformin and aspirin significantly inhibited pancreatic cancer cell growth in vitro and in vivo by regulating the pro- and anti-apoptotic Bcl-2 family members, supporting the continued investigation of this two drug combination as chemopreventive or chemotherapeutic agents for pancreatic cancer.     

Knock-down of NDRG2 sensitizes cervical cancer Hela cells to cisplatin through suppressing Bcl-2 expression

ABSTRACT: BACKGROUND: NDRG2, a member of N-Myc downstream regulated gene family, plays some roles in cellular stress, cell differentiation and tumor suppression. We have found that NDRG2 expression in cervical cancer Hela cells increases significantly upon stimulation with cisplatin, the most popular chemotherapeutic agent currently used for the treatment of advanced cervical cancer. This interesting phenomenon drove us to evaluate the role of NDRG2 in chemosensitivity of Hela cells. METHODS: In the present study, RNA interference was employed to down-regulate NDRG2 expression in Hela cells. RT-PCR and Western blot were used to detect expression of NDRG2, Bcl-2 and Bax in cancer cells. Real-time PCR was applied to detect miR-15b and miR-16 expression levels. Drug sensitivity was determined with MTT assay. Cell cloning efficiency was evaluated by Colony-forming assay. Apoptotic cells were detected with annexin V staining and flow cytometry. RESULTS: In vitro drug sensitivity assay revealed that suppression of NDRG2 could sensitize Hela cells to cisplatin. Down-regulation of NDRG2 didn't influence the colony-forming ability but promoted cisplatin-induced apoptosis of Hela cells. Inhibition of NDRG2 in Hela cells was accompanied by decreased Bcl-2 protein level. However, Bcl-2 mRNA level was not changed in Hela cells with down-regulation of NDRG2. Further study indicated that miR-15b and miR-16, two microRNAs targetting Bcl-2, were significantly up-regulated in NDRG2-suppressed Hela cells. CONCLUSIONS: These data suggested that down-regulation of NDRG2 could enhance sensitivity of Hela cells to cisplatin through inhibiting Bcl-2 protein expression, which might be mediated by up-regulating miR-15b and miR-16.     

Aspirin inhibits ErbB2 to induce apoptosis in cervical cancer cells

The use of aspirin is associated with a lower risk of many cancer types. However, there are few reports about cervical cancer. The proto-oncogene ErbB2 is overexpressed in cervical cancer, and considered as a therapeutic target. In the present study, we investigated whether aspirin had therapeutic value in cervical cancer and examined the effects of aspirin on the amplification and expression of ErbB2. To investigate the effects of aspirin on apoptosis and proliferation, we tested apoptosis by Hoechst 33258 staining and Annexin V-FITC/PI method; MTT assay and colony formation assay were used to detect proliferation. Induction of apoptosis and inhibition of proliferation were observed in HeLa cells incubated with aspirin. Western blot and immunocytochemical staining showed that aspirin induced a dose- and time-dependent reduction of ErbB2 expression that was due to proteosome-mediated degradation of this protein. To further investigate the underlying mechanism by which aspirin exerts its apoptosis effects, we studied the ErbB2 downstream cell survival signaling pathways and the expression of anti-apoptosis gene Bcl-2. We found that aspirin inhibited the activation of extracellular signal-regulated kinase (ERK) and AKT. The inhibition of Bcl-2 expression was also observed. These data reveal that aspirin significantly induces apoptosis and inhibits proliferation, which maybe via inhibiting ErbB2 downstream cell survival signaling pathways. Taken together, our article describes a novel mechanism of action for anti-tumor activity of aspirin and implicates aspirin as a novel agent for cervical cancer.     

Increased expression of phospho-acetyl-CoA carboxylase protein is an independent prognostic factor for human gastric cancer without lymph node metastasis

Triptolide is a traditional Chinese medicinal herb-derived antineoplastic agent. However, its antitumor activity against gynecologic carcinomas has not yet been well described. It is the purpose of this article to investigate the effect and mechanism of triptolide in human ovarian cancer using both A2780 (p53 wild) and OVCAR-3 (p53 mutated) cells. Our results showed that triptolide exerted a potent inhibitory effect on the growth and proliferation of both cell lines in a dose- and time-dependent manner and that the effect was independent of the expression of p53. In contrast, triptolide had only a marginal cytotoxicity in noncancerous ovary cells, lung fibroblast cells, and macrophage cells, indicating differential inhibitory effects of the drug on cell growth between ovarian cancer cells and normal tissue cells. Exposure of the ovarian cancer cells to triptolide induced apoptosis, as evaluated by annexin V/propidium iodide-labeled flow cytometry. Triptolide-induced apoptosis was accompanied by cytochrome c release and caspase-3 activation and was associated with downregulation of Bcl-2 and upregulation of Bax. Cell cycle analysis demonstrated that treatment with triptolide induced cell cycle S phase arrest in A2780 cells and G2/M phase arrest in OVCAR-3 cells. Further detection by Western blotting revealed that the cell cycle arrest by triptolide in both cell lines occurred in concert with increased expression of p21^CIP1/WAF1. This study shows that triptolide selectively kills ovarian cancer cells with different p53 status predominantly through regulating the coordinate and dynamic cellular processes of proliferation and apoptosis, thereby making it a promising chemotherapeutic agent against a broad spectrum of ovarian carcinomas.     

维泰醇和紫杉醇对U14细胞抗肿瘤作用的研究

目的:研究比较维泰醇和紫杉醇对宫颈癌U14细胞抗肿瘤的作用,及维泰醇抗宫颈癌作用的特点及机制.方法:采用MTT法、AO/EB染色法及免疫细胞化学法等观察、比较维泰醇及紫杉醇抑制宫颈癌细胞增殖及诱导凋亡的能力.结果:二者均能显著抑制U14细胞的增殖,维泰醇抑制U14细胞增殖的能力低于紫杉醇.维泰醇、紫杉醇对U14细胞48h的IC50值分别为7.02μmol·L-、0.71 μmol·L-1.7μmol·L-1的维泰醇与0.7μmol·L-1的紫杉醇诱导宫颈癌U14细胞凋亡的能力相当.二者下调宫颈癌U14细胞内Bcl-2表达的能力相当,但7μmol·L-1维泰醇下调Bax表达的能力稍弱于0.7μmol· L-1紫杉醇.结论:维泰醇及紫杉醇均可抑制宫颈癌U14细胞增殖并诱导其凋亡,而维泰醇因其较低的细胞毒性及成本低廉有望成为新的抗肿瘤药物.     

Ciprofloxacin inhibits cell growth and synergises the effect of etoposide in hormone resistant prostate cancer cells

Prostate cancer is the most commonly diagnosed cancer and the second leading cause of cancer related deaths in men in the United States. Ciprofloxacin is a relatively non-toxic antibiotic that can be easily administered orally with large volume of distribution and good tissue penetration. Studies from others and our laboratory have recently reported its anti-tumor activity in a variety of human tumor cells. In our current experiment, we studied the effect of ciprofloxacin on a hormone resistant prostate cancer (HRPC) cell line, PC-3. Our study shows significant in vitro cell growth inhibition of PC-3 cell line (p=0.0001) and also shows that there is a synergistic increase in the antiproliferative effect of etoposide when these cells are pretreated with ciprofloxacin for 24 h, prior to etoposide exposure (p=0.0001). Western blot analysis of the protein extracts from these cells showed down-regulation of Bcl-2, altering the ratio of Bax:Bcl-2 favoring apoptosis. In our study no significant effect was seen on p21WAF1 expression by the combination of ciprofloxacin and etoposide but there was down-regulation of p21WAF1 gene by ciprofloxacin alone. Ciprofloxacin also inhibited NF-kappaB binding to DNA. Further studies in this area are warranted as the roles of p21WAF1, Bax/Bcl-2 and NF-kappaB may be important molecular events in mediating the antiproliferative and apoptosis inducing effect of etoposide in combination with ciprofloxacin in HRPC cells.     

姜黄素对子宫颈癌HeLa细胞增殖抑制作用及其机制的研究

目的:探讨姜黄素(Curcum in)对体外培养人子宫颈癌HeLa细胞抗癌作用及分子机制。方法:MTT法检测细胞增殖,流式细胞仪检测凋亡和细胞周期,PI/Hoechst33258荧光双染法检测细胞凋亡,W estern b lot法检测细胞凋亡相关蛋白Bc l-2和Bax蛋白的表达。结果:姜黄素对HeLa细胞生长有抑制作用,并呈剂量依赖性;流式细胞仪分析证实姜黄素能使HeLa细胞阻滞在S期,并出现亚二倍体凋亡峰;荧光双染法可见凋亡细胞;W estern b lot结果显示Bax蛋白表达均上调,而Bc l-2的表达无明显影响。结论:姜黄素对人子宫颈癌HeLa细胞的增殖具有显著的抑制作用并可诱导细胞凋亡;Bax蛋白的表达上调可能参与了诱导细胞凋亡。     

Synergistic Anticancer Activity of 5-Aminolevulinic Acid Photodynamic Therapy in Combination with Low-dose Cisplatin on Hela Cells

Objective: Photodynamic therapy (PDT ) is a promising modality for the treatment of various tumors.In order to assist in optimizing treatment, we applied 5-ALA/PDT in combination with low-dose cisplatin toevaluate cytotoxicity in Hela cells. Methods: Antiproliferative effects of 5-ALA/PDT and cisplatin, alone and incombination, were assessed using MTT assay. To examine levels of apoptosis, Hela cells treated with 5-ALA/PDT,and combination treatment were assessed with Annexin-V/PI by flow cytometry. To investigate the molecularmechanisms underlying alterations in cell proliferation and apoptosis, Western blot analysis was conducted todetermine the expression of p53, p21, Bax and Bcl-2 proteins. Results: MTT assays indicated that combinationtreatment obviously decreased the viability of Hela cells compared to individual drug treatment. In addition,it was confirmed that exposure of Hela cells to 5-ALA/PDT in combination with low-dose cisplatin resulted inmore apoptosis in vitro. Synergistic anticancer activity was related to upregulation p53 expression and alterationin expression of p21, Bcl-2 and Bax. Conclusion: Our findings suggest that administration of 5-ALA/PDT incombination with the low-dose cisplatin may be an effective and feasible therapy for cervical cancer.     

白屈菜碱对KB细胞株的抗肿瘤作用机制探讨

目的:探讨白屈菜碱(chelidonine)对人口腔上皮样癌细胞KB细胞株的抗肿瘤作用机制。方法:以不同浓度的白屈菜碱作用于体外培养的KB细胞株24、48、72 h,应用MTT检测细胞生长抑制率;Transwell小室检测肿瘤细胞的侵袭作用;流式细胞仪检测细胞凋亡率;免疫印迹实验分析Caspase-3、Bax、Bcl-2、MMP-2、MMP-9信号通路相关蛋白的表达水平。结果:MTT结果显示白屈菜碱对KB细胞株的增殖具有明显的抑制作用,且呈时间剂量依赖性;侵袭试验结果表明,白屈菜碱能够抑制KB细胞侵袭作用,且随着浓度的增大,抑制侵袭作用增强;流式双染检测白屈菜碱作用KB细胞24 h后细胞的凋亡率,与对照组相比差异有统计学意义;蛋白免疫印迹试验显示白屈菜碱组的Caspase-3、Bax表达明显上调,Bcl-2、MMP-2、MMP-9表达下调,与对照组相比差异有统计学意义。结论:白屈菜碱对KB细胞具有明显的抑制增殖、侵袭和促进凋亡的作用;其抗肿瘤机制可能与下调Bcl-2、MMP-2、MMP-9,上调Caspase-3、Bax的表达有关。     

Cav3.1在宫颈癌组织中的表达及靶向下调Cav3.1对宫颈癌HeLa细胞增殖和凋亡的影响

目的:分析Cav3.1在宫颈癌组织中的表达及靶向下调Cav3.1对人宫颈癌HeLa细胞增殖和凋亡的影响。方法:采用免疫组织化学染色法检测Cav3.1在68例宫颈癌组织和40例非癌宫颈组织中的表达;实时定量聚合酶链反应（Real-time PCR）、Western blot检测宫颈癌HeLa细胞中Cav3.1的表达;采用siRNA瞬时转染技术靶向下调Cav3.1表达,CCK-8检测下调Cav3.1表达后宫颈癌HeLa细胞增殖情况,流式细胞仪检测下调Cav3.1表达后宫颈癌HeLa细胞凋亡情况;Western blot检测宫颈癌HeLa细胞中Bcl-2、Bax、Cleaved-Caspase3的表达。结果:Cav3.1在宫颈癌组织中的表达显著高于对照组（P＜0.01）。宫颈癌HeLa细胞中Cav3.1的表达水平显著高于HcerEpic 细胞（P＜0.01）。与对照组相比,siRNA-Cav3.1组的Cav3.1相对表达水平显著下降（P＜0.01）。与空白对照组、mock组相比,siRNA-Cav3.1组HeLa细胞的增殖能力减弱,凋亡能力增强,差异有统计学意义（P＜0.01）。Western blot显示siRNA-Cav3.1组Bax、Cleaved-Caspase3的相对表达量比对照组升高,而Bcl-2降低(P＜0.01)。结论:Cav3.1在宫颈癌组织和细胞中高表达。靶向下调Cav3.1可以抑制HeLa细胞的增殖、促进其凋亡。Cav3.1在宫颈癌的生物学行为中可能起着关键的作用,有望成为一种新的有效的宫颈癌治疗靶点及肿瘤检测的分子生物学标志物。     

阿帕替尼调控WWOX对子宫内膜癌细胞增殖、凋亡、迁移、侵袭的影响及其机制研究

目的:探讨阿帕替尼（Apatinib）是否通过包含氧化还原酶的WW结构域（WWOX）影响子宫内膜癌细胞增殖、凋亡、迁移、侵袭。方法:噻唑蓝（MTT）比色法检测4 μmol/L、8 μmol/L、16 μmol/L、32 μmol/L Apatinib作用于子宫内膜癌细胞HEC-1 24 h、48 h、72 h后的细胞活性,流式细胞术检测细胞凋亡率;蛋白质印迹法（Western blot）检测细胞周期蛋白D1（Cyclin D1）、p21、B细胞淋巴瘤/白血病-2（Bcl-2）、Bcl-2相关X蛋白（Bax）、基质金属蛋白酶-2（MMP-2）、E-钙黏蛋白（E-cadherin）、WWOX蛋白水平,Transwell小室法检测迁移细胞数、侵袭细胞数。在HEC-1中转染pcDNA3.1-WWOX,或转染si-WWOX并用16 μmol/L Apatinib进行处理,采用上述方法评估细胞增殖、凋亡、迁移、侵袭情况。结果:Apatinib明显降低HEC-1细胞活性（P＜0.05）,呈剂量、时间依赖性;Apatinib显著增加HEC-1细胞凋亡率及p21、Bax蛋白表达量（P＜0.05）,呈剂量依赖性;Apatinib明显降低Cyclin D1、Bcl-2蛋白表达量（P＜0.05）,呈剂量依赖性;16 μmol/L Apatinib显著减少HEC-1细胞的迁移细胞数、侵袭细胞数、MMP-2蛋白表达量（P＜0.05）,明显提高E-cadherin、WWOX蛋白表达量（P＜0.05）。过表达WWOX明显降低HEC-1细胞中Cyclin D1、Bcl-2、MMP-2蛋白表达量、细胞活性、迁移细胞数、侵袭细胞数（P＜0.05）,提高p21、Bax、E-cadherin、WWOX蛋白表达量及细胞凋亡率（P＜0.05）。抑制WWOX表达逆转了Apatinib对HEC-1细胞中Cyclin D1、Bcl-2、MMP-2蛋白表达量、细胞活性、迁移、侵袭的抑制作用,以及逆转了其对p21、Bax、E-cadherin、WWOX蛋白表达量、细胞凋亡的促进作用。结论:阿帕替尼通过调控WWOX表达,抑制子宫内膜癌细胞增殖、迁移、侵袭,并诱导细胞凋亡。     

Analysis of Bcl-2, Bax and Survivin genes in uterine cancer.

To investigate the role of the apoptosis-related genes, Bcl-2, Bax and Survivin genes were analyzed. For the Bax gene, abnormality was detected in 1 of 7 cervical and 1 of 6 endometrial cancer cell lines, 1 of 25 cervical cancer tissues and none of 17 endometrial cancer tissues using PCR-SSCP. In 4 cervical and 2 endometrial cancer cell lines, the ratio of Bcl-2 to Bax expression was higher than the control ratio using Western blotting. Survivin mRNA was detectable in all cell lines and all cancer tissues. The data suggested that these apoptosis-related genes may play important roles in the pathway of carcinogenesis of human uterine cancer.     

Plumbagin对人高转移大细胞肺癌细胞系抑制作用的研究

目的:研究Plumbagin时人高转移大细胞肺癌L9981细胞系的体外抗肿瘤作用,并初步探讨其机制.方法:不同浓度Plumbagin处理L9981细胞系,采用MTT法观察对肿瘤细胞增殖的影响,确定药物IC50;采用流式细胞术检测对细胞系诱导凋亡的作用;采用Boyden小室侵袭实验检测对体外侵袭力的抑制作用.以IC50 Plumbagin处理L9981细胞系,于处理后6、24、48 h收获细胞,以实时定量PCR方法检测Bcl-2、Bax、VEGF和CYCD1等基因的mRNA表达变化.结果:MTT法显示,Plumbagin明显抑制L9981细胞系的细胞增殖(F=39.535,P=0.000),IC50为9.0 μmol/L;Plumbagin对L9981细胞系具有体外诱导凋亡作用(F=23.671,P=0.000),且明显抑制其体外侵袭能力.Bodyen小室侵袭实验检测对照组和Plumbagin组平均穿膜细胞数分别为228.17±55.12和9.83±3.87,差异有统计学意义,t=13.598,P=0.000.Plumbagin处理L9981细胞系后不同时间点检测结果显示,Bcl-2、VEGF和CYCD1基因表达均逐渐降低,bax基因表达逐渐增高,组间差异有统计学意义(F=13.520,P=0.000;F=15.778,P=0.000;F=10.163,P=0.000;F=18.635,P=0.000).结论:Plumbagin对大细胞肺癌L9981细胞系具有明确的抗肿瘤作用.Plumbagin通过多种作用机制发挥其抑癌作用,显示了其成为抗大细胞肺癌药物的前景.     

Synergism of Cytotoxicity Effects of Triptolide and Artesunate Combination Treatment in Pancreatic Cancer Cell Lines

Background: Triptolide, extracted from the herb Tripteryglum wilfordii Hook.f that has long been used as anatural medicine in China, has attracted much interest for its anti-cancer effects against some kinds of tumoursin recent years. Artesunate, extracted from the Chinese herb Artemisia annua, has proven to be effective andsafe as an anti-malarial drug that possesses anticancer potential. The present study attempted to clarify iftriptolide enhances artesunate-induced cytotoxicity in pancreatic cancer cell lines in vitro and in vivo. Methods:In vitro, to test synergic actions, cell viability and apoptosis were analyzed after treatment of pancreatic cancercell lines with the two agents singly or in combination. The molecular mechanisms of apoptotic effects were alsoexplored using qRT-PCR and Western blotting. In vivo, a tumor xenograft model was established in nude mice,for assessment of inhibitory effects of triptolide and artesunate. Results: We could show that the combinationof triptolide and artesunate could inhibit pancreatic cancer cell line growth, and induce apoptosis, accompaniedby expression of HSP 20 and HSP 27, indicating important roles in the synergic effects. Moreover, tumor growthwas decreased with triptolide and artesunate synergy. Conclusion: Our result indicated that triptolide andartesunate in combination at low concentrations can exert synergistic anti-tumor effects in pancreatic cancercells with potential clinical applications.     

羟喜树碱通过诱导自噬抗宫颈癌的机制研究

目的探讨抗肿瘤药物羟喜树碱(HCPT)对宫颈癌HeLa细胞作用的机制。方法 CCK8检测Hela细胞增殖,Western blot检测自噬和凋亡相关蛋白的表达,GFP-LC3 shRNA转染和Hoechst染色后,荧光显微镜下观察细胞自噬特异小体量的改变以及凋亡形态学的变化。结果 HCPT抑制Hela细胞生长呈浓度依赖性(P<0.05),IC503μmol/L HCPT作用Hela细胞后,自噬相关蛋白Beclin1、p62的表达以及LC3-Ⅱ/LC3-Ⅰ比值发生改变,差异有显著性意义(P均<0.05);凋亡相关蛋白Bax、cleaved caspase-3、Bcl-2表达也发生明显改变(P均<0.05);荧光显微镜下观察Hela细胞带有GFP-LC3的自噬体增加,凋亡细胞也增多(P均<0.05)。结论 HCPT能够诱导HeLa细胞中自噬相关基因Beclin1、p62以及LC3的表达增强,从而激活细胞自噬发生;且HCPT能够激活宫颈癌HeLa细胞发生自噬,进而诱导细胞凋亡来达到抗肿瘤目的。     

紫杉醇脂质体对卵巢癌细胞生长抑制作用的实验研究

目的分析紫杉醇脂质体对卵巢癌SKOV-3细胞的生长抑制作用,观察药物作用的时间-浓度关系,探究药物作用机制。方法应用不同剂量紫杉醇脂质体对SKOV-3细胞进行处理,通过MTT检测细胞存活率,倒置显微镜观察细胞形态,流式细胞术检测细胞凋亡作用及其对细胞周期的阻滞状态,Western blot分析Bcl-2基因蛋白表达情况。利用SPSS 13.0对数据进行统计学分析。结果紫杉醇脂质体对SKOV-3细胞有明显的剂量-时间依赖效应。紫杉醇与紫杉醇脂质体均可将SKOV-3细胞阻滞在G2/M期,且随药物浓度增加,凋亡细胞所占比例逐渐增加。通过Western blot方法发现,紫杉醇脂质体作用后SKOV-3细胞Bcl-2蛋白表达明显下降,Bax蛋白表达明显上调,Bax/Bal-2比例明显上调。结论紫杉醇以脂质体为转运载体后,并未改变其对卵巢癌SKOV-3细胞的抑制作用及作用周期,具有较好的临床应用前景。     

靶向HPV18E6基因siRNA对HeLa细胞p21、VEGF、Bax 和Bcl-2基因的影响

 目的 探讨针对人乳头瘤病毒18型E6基因的特异性小干扰RNA（siRNA）对宫颈癌HeLa细胞p21、VEGF、Bax和Bcl-2基因的影响。 方法 采用脂质体法将特异性siRNA瞬时转染HeLa细胞,半定量RT-PCR检测siRNA转染后HeLa细胞中p21、血管内皮生长因子（VEGF）、Bax和Bcl-2 mRNA的变化,免疫组化检测HeLa细胞中p21和VEGF蛋白的变化。 结果 RT PCR检测结果显示转染后24、48、 72h p21和Bax mRNA的表达与转染前比较均有升高。转染后24、48、72h VEGF和Bcl-2 mRNA的表达与转染前比较均有降低。免疫组化检测结果显示转染后48、72h p21蛋白的表达与转染前比较均有升高。转染后48、72h VEGF蛋白的表达与转染前比较均有降低。 结论 靶向HPV18 E6基因的siRNA可有效干扰宫颈癌HeLa细胞中p21、VEGF、 Bax和Bcl-2基因的表达,从而抑制细胞增殖。