姜黄素与5-FU联用对结肠癌SW480细胞的生长抑制与凋亡诱导作用的研究北大核心CSCD

本文应用MTT检测法、基于EB/AO双染的荧光显微观察法和FITC/PI双染的流式细胞检测技术,从细胞生长、细胞凋亡和细胞周期等方面研究了姜黄素与5-FU联用对结肠癌SW480细胞的效应。结果显示,姜黄素(25μM)分别与低剂量(2.4μM)、中剂量(4.8μM)5-FU联合作用能有效地抑制SW480细胞的生长,诱导细胞凋亡并将细胞周期阻滞在S期。姜黄素与低剂量5-FU联用组的效果好于中剂量(4.8μM)5-FU单用组(P<0.05),而姜黄素与中剂量5-FU联用组的效果好于高剂量(9.6μM)5-FU单用组(P<0.05),提示姜黄素能增强5-FU抗结肠癌SW480细胞的作用或对5-FU有协同效应。本研究为临床上应用姜黄素作为5-FU治疗结肠癌的辅助用药,以减少5-FU的使用剂量,从而降低其毒副作用提供了初步的实验依据。     

姜黄素与5-FU联用对结肠癌SW480细胞的生长抑制与凋亡诱导作用的研究

本文应用MTT检测法、基于EB/AO双染的荧光显微观察法和FITC/PI双染的流式细胞检测技术,从细胞生长、细胞凋亡和细胞周期等方面研究了姜黄素与5-FU联用对结肠癌SW480细胞的效应。结果显示,姜黄素(25μM)分别与低剂量(2.4μM)、中剂量(4.8μM)5-FU联合作用能有效地抑制SW480细胞的生长,诱导细胞凋亡并将细胞周期阻滞在S期。姜黄素与低剂量5-FU联用组的效果好于中剂量(4.8μM)5-FU单用组(P0.05),而姜黄素与中剂量5-FU联用组的效果好于高剂量(9.6μM)5-FU单用组(P0.05),提示姜黄素能增强5-FU抗结肠癌SW480细胞的作用或对5-FU有协同效应。本研究为临床上应用姜黄素作为5-FU治疗结肠癌的辅助用药,以减少5-FU的使用剂量,从而降低其毒副作用提供了初步的实验依据。     

姜黄素诱导人胰腺癌PANC-1细胞凋亡的机制研究

目的：胰腺癌恶性程度高、进展快、预后差,姜黄素对于抑制恶性肿瘤的发生和进程具有广泛的生物学效应。但姜黄素能否诱导人胰腺癌细胞凋亡,其具体作用机制如何？目前仍无报道。本研究拟观察姜黄素对人胰腺癌PANC．1细胞凋亡的影响,探讨姜黄素诱导PANC．1细胞凋亡的机制。方法：不同浓度姜黄素处理人胰腺癌PANC-1细胞,流式细胞仪检测PANC-1细胞凋亡率,并分析Caspase-9和Caspase-3活性的变化,同时通过RT—PCR和Westemblot分析PANC-1细胞中P53表达的变化。结果：PANC-1细胞经不同浓度的姜黄素处理后,可以显著诱导细胞凋亡,并呈现一定的剂量依赖性,提示姜黄素具有一定抗肿瘤活性。姜黄素能够同时增加Caspase-9和Caspase-3的活性,并呈现一定的剂量依赖性,提示姜黄素可能通过Caspase-9和Caspase-3途径来诱导PANC．1细胞凋亡的发生。RT—PCR和westernblot结果显示,姜黄素可以显著增加PANC-1细胞中P53蛋白表达水平。结论：姜黄素可以显著诱导PANC-1细胞凋亡的发生,提高Caspase-9和Caspase-3的活性,同时增加的P53表达,并呈现一定的剂量依赖性,提示姜黄素诱导PANC-1细胞凋亡的过程可能与增加细胞中Caspase-9,Caspase-3以及P53的表达有关。本研究探讨了姜黄素诱导PANC-1细胞凋亡的分子机制,为姜黄素的进一步应用提供了新的思路和理论支持,在人胰腺癌的临床治疗中具有一定的潜在应用价值。     

姜黄素类化合物生物合成研究进展

姜黄素类化合物是植物中一类稀少的二酮类化合物,存在于姜科、天南星科植物的块根或根茎中,是姜黄等植物中主要活性成分,因具有抗氧化、抗癌等诸多药理活性而被广泛应用于食品领域和新药研发中。因其苯环侧链取代基不同,姜黄素类化合物可进一步分为姜黄素、去甲氧基姜黄素、双去甲氧基姜黄素等。目前,姜黄素类化合物主要是通过植物提取法获得,产量远远不能满足市场需求。随着合成生物学和代谢工程技术的发展,采用生物合成法生产姜黄素类化合物开始受到研究人员的广泛关注。近年来,研究人员通过基因挖掘及酶学手段鉴定了姜黄中姜黄素合成途径中的关键酶,并在大肠杆菌Escherichia coli、耶氏解酯酵母Yarrowia lipolytica、恶臭假单胞菌Pseudomonas putida和米曲霉Aspergillus oryzae中重塑其生物合成途径,成功实现了其异源生物合成。文中首先介绍了姜黄素的生物活性及其应用、总结了姜黄中的姜黄素合成途径,并且讨论了姜黄素合成酶的催化机制,进而详尽综述了其生物合成的最新研究进展,特别是代谢工程策略方面,并对其未来发展方向进行了展望。     

姜黄素联合顺铂对人骨肉瘤细胞增殖和凋亡的影响

目的:观察姜黄素联合顺铂对人骨肉瘤细胞MG-63增殖和凋亡的影响。方法:采用不同浓度的姜黄素、顺铂和姜黄素联合顺铂处理人骨肉瘤细胞MG-63不同时间,通过MTT法检测其对MG-63细胞生长的抑制作用;平板克隆实验检测其对MG-63细胞克隆形成能力的影响;流式细胞仪检测其对MG-63细胞凋亡的影响。结果:单用姜黄素或顺铂均可以时间和浓度依赖性方式抑制骨肉瘤细胞MG-63的增殖。与空白对照组相比,单用10μmol/L姜黄素和2、4μmol/L顺铂可抑制MG-63细胞的增殖,降低其克隆形成率并提高细胞凋亡率(P<0.05);而与姜黄素和顺铂单用处理相比,10μmol/L姜黄素分别与2、4μmol/L顺铂联合应用,可更显著抑制MG-63细胞的增殖,降低其克隆形成率并提高细胞凋亡率(P<0.01)。结论:姜黄素联合顺铂与单药相比能够显著抑制人骨肉瘤细胞MG-63细胞的增值,促进其凋亡,两药对骨肉瘤细胞的杀伤效应具有一定的协同性。     

凋亡诱导因子在姜黄素诱导的大鼠肺成纤维细胞凋亡中的作用

目的：研究姜黄素对肺纤维化大鼠肺成纤维细胞增殖、凋亡的影响,探讨凋亡诱导因子（AIF）在肺成纤维细胞凋亡中的作用。方法：将体外培养的肺纤维化大鼠成纤维细胞,分别于不同浓度的姜黄素（5、10、20、40μM）和caspase-3抑制剂Z-DEVD-fmk（20μM）孵育,观测细胞生长状态变化。MTT检测成纤维细胞增殖抑制率;流式细胞仪检测细胞凋亡率;Western-Blot测定凋亡诱导因子（AIF）蛋白表达及核转位结果：流式细胞术检测细胞凋亡,5～40μM姜黄素处理12 h,其凋亡率呈浓度依赖,对照组相比,差异显著;而抑制caspase-3并不能完全阻止细胞凋亡。Western-Blot结果显示,姜黄素处理组出现凋亡诱导因子（AIF）蛋白表达与核转位,抑制caspase-3活性后未检测出AIF表达结论：姜黄素可抑制肺成纤维细胞增殖,其诱导大鼠肺成纤维细胞凋亡,可能与线粒体释放AIF有关。     

凋亡诱导因子在姜黄素诱导的大鼠肺成纤维细胞凋亡中的作用

目的:研究姜黄素对肺纤维化大鼠肺成纤维细胞增殖、凋亡的影响,探讨凋亡诱导因子(AIF)在肺成纤维细胞凋亡中的作用.方法:将体外培养的肺纤维化大鼠成纤维细胞,分别于不同浓度的姜黄素(5、10、20、40μM)和caspase-3抑制剂Z-DEVD-fmk(20μM)孵育,观测细胞生长状态变化.MTT检测成纤维细胞增殖抑制率;流式细胞仪检测细胞凋亡率;Western-Blot测定凋亡诱导因子(AIF)蛋白表达及核转位结果:流式细胞术检测细胞凋亡,5～40μM姜黄素处理12 h,其凋亡率呈浓度依赖,对照组相比,差异显著;而抑制caspase-3并不能完全阻止细胞凋亡.Western-Blot结果显示,姜黄素处理组出现凋亡诱导因子(AIF)蛋白表达与核转位,抑制caspase-3活性后未检测出AIF表达结论:姜黄素可抑制肺成纤维细胞增殖,其诱导大鼠肺成纤维细胞凋亡,可能与线粒体释放AIF有关.     

姜黄素对人食管癌EC9706细胞凋亡的诱导作用

目的:应用姜黄素处理人食管癌EC9706细胞,研究姜黄素对人食管癌EC9706细胞凋亡的诱导作用。方法:应用细胞计数、流式细胞仪、琼脂糖凝胶电泳、Hoechst染色、H.E染色和透射电镜检测经姜黄素诱导处理后人食管癌EC9706细胞的凋亡。结果:经姜黄素诱导处理后,人食管癌EC9706细胞生长抑制率达69.9%;细胞周期检测出现亚二倍体(亚G1期)细胞峰值,细胞凋亡率达23%;琼脂糖凝胶电泳显示出细胞凋亡典型的180-200 bp及其倍体的DNA"梯状"条带;Hoechst染色显示细胞核内出现浓染致密的固缩形态或颗粒状荧光;光镜和电镜下可见典型的细胞凋亡特征:细胞体积缩小,染色体凝集,可见有成群或单独存在的凋亡细胞,电镜下可见凋亡小体存在。结论:姜黄素能够有效诱导人食管癌EC9706细胞的凋亡,从而进一步为食管癌等恶性肿瘤疾病的治疗和凋亡机理的研究提供重要基础和科学依据.     

姜黄素抗肿瘤作用及机制研究进展

姜黄素是从草本植物姜黄、莪术等根茎中提取的一种植物多酚,有着广泛的药理作用,具有抗心血管疾病、抗肿瘤、抗微生物、抗抑郁、抗炎、抗氧化等生物学功能。抗肿瘤是姜黄素主要生物活性之一,抗肿瘤机制主要有:抑制肿瘤细胞增殖,诱导肿瘤细胞凋亡,抗肿瘤侵袭及转移,逆转肿瘤细胞耐药性及增加对化疗的敏感性等。本文就其抗肿瘤机制的研究进行综述,为姜黄素的进一步开发利用提供基础。     

姜黄素抑制大鼠气道平滑肌细胞增殖和诱导凋亡的作用

目的:探讨姜黄素对大鼠气道平滑肌细胞(airway smooth muscle cells,ASMCs)增殖和凋亡的影响.方法:采用改良组织块消化法培养原代大鼠气道平滑肌细胞,以PDGF诱导ASMCs增殖建立模型.MTT法检测不同浓度姜黄素抑制ASMCs增殖情况.Hoechst 33342染色和DNA Ladder检测细胞凋亡,Western Blot检测ERK1/2和磷酸化ERK1/2的表达.结果:①MTT检测给予姜黄素处理12 h后,与模型组相比较,10 μmol/l组、20μmol/l组和40 μmol/l组的细胞平均抑制率均增加显著.P<0.05;48 h后各浓度组抑制率均升高.②Hoechst 33342观察到10μmol/I、20μmol/1和40 μmol/l姜黄素组中强荧光细胞比例随姜黄素刺量增大而增多,细胞核内多个不均一蓝染现象.③DNA Ladder观察到40μmol/l组姜黄素处理组出现梯状分布.④姜黄素(40 μmol/1)与PDGF(20 ng/m1)共同处理30 min和60 min后P-ERK1/2蛋白表达水平显著降低.结论:姜黄素对ASMCs增殖有抑制作用,同时高浓度的姜黄素可促进AsMCs凋亡,可能与下调ERK1/2的表达有关.     

KRN5500, a novel antitumor agent, induces apoptosis or cell differentiation in HL-60 cells

BACKGROUND: KRN5500, a derivative of spicamycin, shows antitumor activity against a variety of tumor cell lines. However, the mechanism of cytotoxic action has remained unclear. METHODS: The viability of HL-60 human leukemic cells treated with KRN5500 was studied by the dye exclusion assay. Induction of apoptosis and effects on the cell cycle were investigated by flow cytometry: We measured cellular DNA content after extraction of fragmented DNA, and apoptosis-induced DNA strand breaks. Cell morphology was observed by light microscopy. DNA strand breaks at a nucleosomal unit were analyzed by electrophoresis. RESULTS: Our data demonstrated that KRN5500 caused inhibition of cell growth, and that apoptosis was the mode of cell death. G(1) phase cells were more susceptible to KRN5500 induced apoptosis. In addition, KRN5500 induced cell differentiation at lower concentration. CONCLUSIONS: It is anticipated that KRN5500 will be used clinically as an anti-leukemic agent. Its mechanism of antitumor action is to induce apoptosis or cell differentiation.     

中药抗肿瘤作用的研究进展

应用中草药抗肿瘤的研究很早就已是医学科技工作者的重要研究领域;但是,近年来中草药抗肿瘤的研究变的越来越火热,越来越深入,许多研究工作已经不单纯局限于抗肿瘤的基本活性,更多的研究已经深入到抗肿瘤作用机理的层面;本文从中药有效成分对诱导肿瘤细胞凋亡、抑制肿瘤血管的生长、诱导肿瘤细胞分化、逆转肿瘤细胞多药耐药性、提高机体免疫力等方面对中药抗肿瘤研究的当前状况进行了综述,具体情况如下：     

A Screening Procedure on the Inhibitors of Substrate-incorporation in Tumor Cells Methodological Survey and Its Evaluation

A comparative study of inhibition on the substrate-incorporation in several species of tumor cells has been achieved in combination with the antibiotics having different action mechanisms. It was thus revealed that a large part of the antitumor antibiotics so far examined showed a marked inhibitory response even at a low concentration. Particularly, the antibiotics whose action mechanism were established primarily on cell membrane were markedly sensitive. An apparent difference in the sensitivity was observed in some groups of antitumor antibiotics which act on nucleic acid synthesis. A methodological survey together with an evaluation of this procedure is discussed.     

Autophagy inhibition enhances celecoxib-induced apoptosis in osteosarcoma

Osteosarcoma (OS) is the most prevalent bone malignancy in childhood and adolescence, with highly aggressive and early systemic metastases. Here, we reported that celecoxib, a selective COX-2 inhibitor in the NSAID class, exhibits strong antitumor activity in dose dependent manner in two OS cell lines-143B and U2OS. We showed that celecoxib inhibits OS cell growth, causes G0/G1-phase arrest, modulates apoptosis and autophagy and reduces migration in OS cells. In addition, the results of fluorescent mitochondrial probe JC-1 test indicated that the mitochondrial pathway mediates celecoxib-induced apoptosis. Significantly, the autophagy inhibitor CQ combined with celecoxib causes greater cell proliferation inhibition and apoptosis. Pharmacologic inhibition of autophagy with another potent autophagy inhibitor SAR405 also enhances celecoxib-mediated suppression of cell viability. These results were confirmed with shRNAs targeting the autophagy-related gene Atg5. In OS tumor xenografts in vivo, celecoxib also presents antitumor activity. Taken together, our results shed light on the function and mechanism of antitumor action of celecoxib for treatment of OS patients.     

Tumor growth retardation and chemosensitizing action of fatty acid synthase inhibitor orlistat on T cell lymphoma: Implication of reconstituted tumor microenvironment and multidrug resistance phenotype

Background

Orlistat, a fatty acid synthase (FASN) inhibitor, has been demonstrated to inhibit tumor cell survival. However, the mechanism(s) of its tumor growth retarding action against malignancies of hematological origin remains unclear. It is also not understood if the antitumor action of orlistat implicates modulated susceptibility of tumor cell to anticancer drugs. Therefore, the present investigation focuses to study the antitumor and chemosensitizing action of orlistat in a murine host bearing a progressively growing T cell lymphoma.

Methods

Tumor-bearing mice were administered with vehicle alone or containing orlistat followed by administration of PBS with or without cisplatin. Tumor progression and survival of tumor-bearing host were monitored along with analysis of tumor cell survival and apoptosis. Tumor ascitic fluid was examined for pH, NO and cytokines. Expression of genes and proteins was investigated by RT-PCR and western blot respectively. ROS was analyzed by DCFDA staining and FASN activity by spectrophotometry.

Results

Orlistat administration to tumor-bearing mice resulted in tumor growth retardation, prolonged life span, declined tumor cell survival and chemosensitization to cisplatin. It was accompanied by increased osmotic fragility, modulated acidosis, expression of ROS, NO, cytokines, MCT-1 and VH⁺ ATPase, Bcl2, Caspase-3, P53, inhibited FASN activity and declined expression of MDR and MRP-1 proteins.

Conclusion

Orlistat manifests antitumor and chemosensitizing action implicating modulated regulation of cell survival, reconstituted-tumor microenvironment and altered MDR phenotype.

General significance

These observations indicate that orlistat could be utilized as an adjunct regimen for improving antitumor efficacy of cisplatin.     

Antitumor and Angiostatic Activities of the Antimicrobial Peptide Dermaseptin B2

Recently, we have found that the skin secretions of the Amazonian tree frog Phyllomedusa bicolor contains molecules with antitumor and angiostatic activities and identified one of them as the antimicrobial peptide dermaseptin (Drs) B2. In the present study we further explored the in vitro and in vivo antitumor activity of this molecule and investigated its mechanism of action. We showed that Drs B2 inhibits the proliferation and colony formation of various human tumor cell types, and the proliferation and capillary formation of endothelial cells in vitro. Furthermore, Drs B2 inhibited tumor growth of the human prostate adenocarcinoma cell line PC3 in a xenograft model in vivo. Research on the mechanism of action of Drs B2 on tumor PC3 cells demonstrated a rapid increasing amount of cytosolic lactate dehydrogenase, no activation of caspase-3, and no changes in mitochondrial membrane potential. Confocal microscopy analysis revealed that Drs B2 can interact with the tumor cell surface, aggregate and penetrate the cells. These data together indicate that Drs B2 does not act by apoptosis but possibly by necrosis. In conclusion, Drs B2 could be considered as an interesting and promising pharmacological and therapeutic leader molecule for the treatment of cancer.     

In vitro and ex vivo vanadium antitumor activity in (TGF-β)-induced EMT. Synergistic activity with carboplatin and correlation with tumor metastasis in cancer patients

Epithelial to mesenchymal transition (EMT) plays a key role in tumor progression and metastasis as a crucial event for cancer cells to trigger the metastatic niche. Transforming growth factor-β (TGF-β) has been shown to play an important role as an EMT inducer in various stages of carcinogenesis. Previous reports had shown that antitumor vanadium inhibits the metastatic potential of tumor cells by reducing MMP-2 expression and inducing ROS-dependent apoptosis. However, the role of vanadium in (TGF-β)-induced EMT remains unclear. In the present study, we report for the first time on the inhibitory effects of vanadium on (TGF-β)-mediated EMT followed by down-regulation of ex vivo cancer stem cell markers. The results demonstrate blockage of (TGF-β)-mediated EMT by vanadium and reduction in the mitochondrial potential of tumor cells linked to EMT and cancer metabolism. Furthermore, combination of vanadium and carboplatin (a) resulted in synergistic antitumor activity in ex vivo cell cultures, and (b) prompted G₀/G₁ cell cycle arrest and sensitization of tumor cells to carboplatin-induced apoptosis. Overall, the findings highlight the multifaceted antitumor action of vanadium and its synergistic antitumor efficacy with current chemotherapy drugs, knowledge that could be valuable for targeting cancer cell metabolism and cancer stem cell-mediated metastasis in aggressive chemoresistant tumors.     

一种新型DHA复合物的抑瘤作用及对Caspase-3凋亡蛋白表达的影响

目的评价一种新型DHA复合物（AT-158）对荷瘤小鼠移植瘤及体外培养肿瘤细胞的抑瘤作用,并对其可能的作用机制做初步探讨。方法建立移植瘤荷瘤小鼠动物模型和体外细胞培养的方法,评价AT-158在体内和体外的抑瘤作用,观察体外培养的Hela细胞在药物作用下的核形态的改变,测定移植瘤中Caspase-3凋亡蛋白表达的变化。结果AT-158在体内和体外均显示显著的抑瘤作用。肿瘤细胞的核形态发生凋亡细胞特征性改变。诱导凋亡执行蛋白Caspase-3表达增加。结论AT-158显示一定的抑瘤效果,具有较高的开发价值。