归肝经中药对肝癌HepG2细胞增殖抑制及凋亡诱导作用的研究

目的 观察归肝经中药对体外人肝癌细胞株HepG2增殖及凋亡的影响,初步探讨归肝经中药抗肝癌作用的趋向性.方法 归肝经中药选取莪术、水蛭、丹参,非归肝经中药选取白花蛇舌草为对照;制备提取物后体外干预HepG2细胞.用四甲基偶氮唑盐(MTT)比色法检测各中药提取物对HepG2细胞增殖的抑制作用,并计算半数抑制浓度(IC50);用细胞计数法、流式细胞仪、吖啶橙/溴化乙锭(AO/EB)双染法分析比较归肝经中药莪术、水蛭、丹参提取物与非归肝经中药白花蛇舌草提取物在IC50药物浓度下对HepG2细胞增殖的影响及诱导凋亡的差异.结果 白花蛇舌草提取物IC50药物浓度对应生药量是丹参提取物的11.39倍,水蛭提取物的16.56倍,莪术挥发油的168.67倍.IC50药物浓度作用下,归肝经中药莪术、水蛭、丹参提取物抑制HepG2细胞增殖作用、诱导细胞凋亡率均强于非归肝经中药白花蛇舌草提取物,归肝经中药可阻止HepG2细胞从G0/G1期进入S期,而白花蛇舌草提取物对HepG2细胞周期无明显影响.结论 归肝经中药对肝癌HepG2细胞增殖抑制及凋亡诱导作用强于非归肝经中药白花蛇舌草,提示归肝经可能与中药抗肝癌趋向作用有关.     

肝癌细胞凋亡的研究

细胞凋亡(ａｐｏｐｔｏｓｉｓ)的概念首先由英国病理学家Ｋｅｒｒ等于1972年提出,用来描述一种在形态学上有别于细胞坏死的细胞死亡过程。细胞凋亡是机体为了维护自身稳定,在基因调控下细胞发生主动消亡的过程。细胞凋亡对肿瘤的发生、发展和治疗具有重要的影响,本文就细胞凋亡与肝癌的相互关系做一综述,以期对肝癌发生发展和治疗研究的进一步深入有所帮助。1　细胞凋亡的认识细胞的死亡方式有两种:一种是坏死(ｎｅｃｒｏｓｉｓ),另一种就是细胞凋亡(ａｐｏｐｔｏｓｉｓ)。细胞凋亡是指细胞在一定生理或病理条件下,遵循一定的程序,最终通过…     

伊马替尼联合槲皮素对K562细胞增殖、凋亡的影响及其机制研究

目的:探讨酪氨酸激酶抑制剂伊马替尼联合槲皮素诱导K562细胞凋亡的机制。方法:将250 nmol/L的伊马替尼、25μmol/L的槲皮素单药及联合作用于K562细胞,通过细胞计数检测细胞增殖,流式细胞仪分析细胞凋亡,蛋白印迹法检测相关蛋白的表达。结果:250 nmol/L伊马替尼联合25μmol/L槲皮素对K562细胞有明显的协同诱导凋亡作用,两药联合较单药处理能明显协同下调p-BCR/ABL、p-Crkl蛋白的表达。结论:伊马替尼和槲皮素协同诱导K562细胞凋亡,其机制可能是主要通过协同抑制BCR/ABL蛋白磷酸化水平,从而抑制下游信号通路的激活,导致细胞凋亡。     

扶正抑瘤方干预肝癌细胞株HepG2增殖和凋亡的实验研究

目的观察扶正抑瘤方对肝癌细胞增殖和凋亡的影响。方法采用体外培养肝癌细胞株HepG2,分别用扶正抑瘤方含药血清高中低剂量组和空白血清组干预。MTT法检测细胞增殖,流式细胞术检测细胞周期和细胞凋亡率。结果扶正抑瘤方含药血清组与空白血清组比较,OD值明显降低(P<0.05),S期细胞含量明显减少(P<0.01),Annexin V+/PI-区域和Annexin V+/PI+区域细胞含量不同程度增多(P<0.05或P<0.01),以高剂量含药血清组作用最为明显。结论扶正抑瘤方含药血清通过干扰肝癌细胞株HepG2 S期的合成有效抑制肝癌细胞的生长,同时诱导肝癌细胞株HepG2的早期和晚期凋亡,清除增殖过度的肝癌细胞。     

青蒿琥酯诱导人肝癌细胞株HepG2凋亡及其机制

目的探讨青蒿琥酯作用人肝癌细胞株HepG2后,对细胞凋亡的影响。方法常规培养人肝癌细胞株HepG2,设立空白对照组、青蒿琥酯不同浓度组(3.125μg/ml、6.25μg/ml、12.5μg/ml、25μg/ml、50μg/ml),对HepG2作用48h后,应用流式细胞术检测细胞凋亡率,同时采用瑞氏染色法观察细胞凋亡;用RT-PCR检测caspase-3mRNA的表达,采用灰度分析比较表达的变化。结果青蒿琥酯(3.125μg/ml、6.25μg/ml、12.5μg/ml、25μg/ml、50μg/ml)处理HepG2细胞48h,呈浓度依赖性诱导细胞凋亡,且当青蒿琥酯浓度在6.25μg/ml以上时,各组凋亡率与对照组比较差异具有统计学意义(P<0.01),瑞氏染色后光镜下可见处理组细胞发生凋亡形态学改变。与对照组比较,各实验组caspase-3的表达显著增加(P<0.01)。结论青蒿琥酯能显著诱导HepG2细胞凋亡,其机制可能与增强凋亡相关基因caspase-3的表达有关。     

槲皮素促进白血病细胞凋亡的分子机理研究进展

目的 槲皮素是存在于多种植物中的黄酮类化合物,具有许多潜在的药用价值,其中抗肿瘤作用是目前研究的热点.本文就槲皮素诱导白血病细胞凋亡的分子机理以及对其他化疗药物增敏作用的研究进展进行综述.     

VX-680抑制肝癌HepG2细胞恶性表型的分子机制研究

目的探究VX-680对肝癌HepG2细胞恶性表型的影响及其分子机制。方法取肝癌细胞系HepG2细胞进行培养,分别给予0μmol/L、4μmol/L、8μmol/L、16μmol/L浓度VX-680进行处理,采用四甲基偶氮唑盐微量酶反应比色(MTT)法、平板克隆法、4',6-二脒基-2-苯基吲哚(DAPI)法、体外HUVEC小管形成实验检测肝癌HepG2细胞增殖、凋亡及血管生成等生物学行为,分别采用逆转录聚合酶链式反应(RT-PCR)、Western Blot法测定细胞磷脂酰肌醇3-激酶(PI3K)、丝氨酸苏氨酸激酶(Akt)、血管内皮生长因子(VEGF)基因mRNA、蛋白表达情况。结果①VX-680各浓度处理组细胞增殖抑制率显著高于对照组(P<0.05),克隆形成数显著低于对照组(P<0.05),随着浓度的升高,增殖抑制率、克隆形成数升高或降低幅度加大(P<0.05)。②DAPI染色实验示,各浓度VX-680作用下细胞可见不同程度凋亡,随浓度升高细胞凋亡数增多,组间比较差异具统计学意义(P<0.05)。③小管生成实验结果显示,与0μmol/L VX-680组比较,4μmol/L、8μmol/L、16μmol/L浓度VX-680作用下小管形成数逐渐减少,随着浓度的升高,小管生成数减少,差异具统计学意义(P<0.05)。④RT-PCR、Western-blot实验显示,随着处理浓度的升高,细胞PI3K、Akt、VEGF基因mRNA、蛋白表达均显著降低,差异具统计学意义(P<0.05)。结论VX-680可抑制肝癌HepG2细胞增殖、凋亡及血管生成作用,且存在明显的剂量效应,这一作用机制可能与其抑制PI3K/Akt通路的活性及VEGF的表达相关。     

载紫杉醇超声微泡造影剂对人肝癌细胞株HepG2增殖影响及诱导凋亡作用研究

目的 探讨超声辐照紫杉醇微泡造影剂对人肝癌细胞株HepG2增殖抑制的影响和诱导凋亡作用.方法 体外培养肝癌细胞,将细胞分4组,即空白对照组,紫杉醇组,超声空白微泡组,超声载紫杉醇微泡组.MTT法观察不同处理组不同时间点对细胞生长的影响,Annexin V-FITC荧光染色检测其对诱导细胞凋亡作用.结果 超声载紫杉醇微泡组对细胞的增殖抑制作用强于其他处理组及对照组;超声载紫杉醇微泡组能够诱导肿瘤细胞发生凋亡.结论 超声辐照紫杉醇微泡造影剂对人肝癌细胞株HepG2生长有明显抑制作用,并诱导细胞凋亡.     

槲皮素对人结肠癌细胞体外增殖、凋亡及细胞周期的影响

目的研究植物化学药物槲皮素对人结肠癌细胞的生长抑制作用和凋亡诱导效应。方法分别用不同浓度的槲皮素对人结肠癌细胞（Lovo细胞株）进行干预,采用MTT检测细胞增殖,流式细胞术检测细胞凋亡及细胞周期。结果与对照组相比,槲皮素对Lovo细胞具有显著的增殖抑制作用（P〈0.05）,细胞增殖抑制随浓度增加、时间延长逐渐降低,呈现量-效、时-效关系。槲皮素引起明显的细胞周期阻滞（P〈0.05）,将细胞周期阻滞在G2/M期。槲皮素呈浓度依赖性诱导细胞凋亡（P〈0.05）。结论槲皮素对结肠癌Lovo具有增殖抑制效应及凋亡诱导效应,是一种具有发展潜力的抗结肠癌药物。     

人参皂苷Rh2诱导人肝癌HepG2细胞凋亡的研究

目的研究人参皂苷Rh2（G-Rh2）对肝癌HepG2细胞增殖抑制和凋亡诱导的作用,并探讨其作用机制。方法用终浓度为5、10、20 mg/L的G-Rh2作用于HepG2细胞,于24 h、48 h及72 h后采用MTT法检测细胞增殖抑制率;72 h后收集各组肝癌HepG2细胞,流式细胞术检测细胞周期及凋亡率;RT-PCR检测survivin mRNA表达。结果 MTT法检测显示,G-Rh2对肝癌HepG2细胞有增殖抑制作用,并存在浓度和时间依赖关系;流式细胞仪检测显示G-Rh2作用后,细胞被阻滞于G0/G1期,随药物质量浓度的增加,细胞凋亡率逐渐增加。RT-PCR结果显示,G-Rh2下调肝癌HepG2细胞survivin mRNA表达。结论 G-Rh2在体外对肝癌HepG2细胞有明显的增殖抑制和凋亡诱导作用,初步推断G-Rh2诱发肝癌细胞凋亡的作用与其对survivin基因表达的抑制有关。     

亚砷酸联合电离辐射对肝癌细胞株HepG2细胞周期及凋亡的影响

目的探讨亚砷酸联合电离辐射对肝癌细胞株HepG2细胞周期及凋亡的影响。方法采用流式细胞仪观察5 mg/ml亚砷酸对肝癌细胞株HepG2细胞凋亡及细胞周期分布情况。结果肝癌细胞株HepG2细胞照射48 h后,对照组、照射组、亚砷酸组、亚砷酸+照射组细胞周期进行了重新分布,G0/G1期细胞比率降低,S期、G2/M期细胞比率增加;细胞凋亡率(%,x珋±s)分别为5.96±0.27、9.07±0.59、15.12±1.61、21.01±2.32,各组间有统计学差异(F=63.41,P=0.000),两两比较均有统计学差异(P0.05)。结论亚砷酸对肝癌细胞株HepG2具有S期、G2/M期阻滞及诱导细胞凋亡的作用。     

RPB5介导蛋白与HBx蛋白共表达对肝癌HepG2细胞凋亡的影响

目的通过乙型肝炎病毒X蛋白(HBx)与RPB5介导蛋白(RMP)在肝癌Hep G2细胞中的共表达,探索RMP与HBx对肝癌细胞凋亡的影响。方法脂质体介导瞬时转染细胞;实时荧光定量RT-PCR和western blot分别检测RMP与HBx在肝癌Hep G2细胞中的表达量;流式细胞仪检测细胞凋亡率;逆转录PCR检测细胞凋亡相关基因Bax、Caspase3、P53、Bcl-2 mRNA相对表达水平,western blot检测凋亡相关蛋白Bax、Bcl-2的表达。结果与未经任何处理的Hep G2细胞比较,转染RMP质粒的稳定表达HBx的Hep G2细胞中RMP、HBx在基因及蛋白质水平表达均显著升高(P0.01);细胞凋亡率显著降低;促凋亡基因Bax、Caspase3和P53 mRNA相对表达水平均显著下调(P0.01),凋亡抑制基因Bcl-2 mRNA相对表达水平显著上调(P0.01);促凋亡蛋白Bax表达量明显降低,抗凋亡蛋白Bcl-2表达量明显升高。结论 RMP与HBx共表达可降低肝癌Hep G2细胞凋亡率,提示RMP和HBx可能在肝癌发生和发展过程中起着重要的作用。     

TIGAR基因真核表达载体的构建及在HepG_2细胞中的作用初探

目的:构建TP53诱导的糖酵解和凋亡调控子(TIGAR)全长cDNA的真核表达载体pEGFP-TIGAR,观察TIGAR在人肝细胞HepG2中的作用。方法:RT-PCR技术扩增获得TIGAR全长cDNA,将扩增的产物克隆,经酶切、DNA测序鉴定正确,构成pEGFP-TIGAR的真核表达重组质粒。利用脂质体将重组质粒转染入HepG2细胞,流式细胞仪和TUNEL法检测细胞凋亡、流式细胞仪检测细胞周期、MIB-1(Ki-67抗原测定)法检测细胞增殖、实时荧光PCR检测mRNA表达和Western-blot检测蛋白质的表达。结果:构建完成的真核表达重组质粒pEGFP-TIGAR,经DNA测序与GenBank中的人TIGARcDNA序列一致。荧光显微镜观察到转染重组质粒的细胞中有绿色荧光蛋白的表达。检测结果显示,转染pEGFP-TIGAR质粒的HepG2晚期凋亡细胞明显减少(P<0.05);S期细胞百分数则明显增加(P<0.05),增殖能力明显增高(P<0.05)。结论:本实验成功构建了pEGFP-TIGAR真核表达质粒,过表达的TIGAR可降低HepG2细胞发生晚期凋亡和促进细胞增殖,为进一步研究TIGAR基因在肿瘤细胞中作用提供了基础。     

A comprehensive view on the quercetin impact on bladder cancer: Focusing on oxidative stress,cellular, and molecular mechanisms

Bladder cancer (BC) is known as a prevalent genitourinary malignancy and has a significant mortality rate worldwide. Despite recent therapeutic approaches, the recurrence rate is high, highlighting the need for a new strategy to reduce the BC cell progression. Quercetin, a flavonoid compound, demonstrated promising anticancer properties and could be used in the management of various malignancies such as BC. This comprehensive review summarized quercetin's cellular and molecular mechanisms underlying anticancer activities. The study's findings indicated that quercetin prevents the proliferation of the human BC cell line, promotes apoptosis of BIU-87 cells, reduces the expression of p-P70S6K, and induces apoptosis by p-AMPK. Moreover, quercetin restricts tumor growth through the AMPK/mTOR cascade and prevents colony formation of human BC cells by triggering DNA damage. Studying this review article will help researchers better understand quercetin's functional role in the prevention and treatment of BC.     

Resveratrol and quercetin down-regulate tissue factor expression by human stimulated vascular cells

Summary.  Background : Epidemiological studies have shown that consumption of wine reduces the risk of coronary heart disease. Resveratrol and quercetin, two polyphenolic compounds found in grapes and red wine, have been shown to contribute to this protection by exerting several biological properties which could be associated with cardioprotection. Tissue factor (TF), the cellular receptor that initiates blood coagulation, plays a primary role both in hemostasis following tissue injury and in the pathogenesis of atherosclerosis which predisposes to thrombosis. Objectives : We investigated the role of resveratrol and quercetin on TF expression by endothelial and mononuclear cells (MN). Methods : Confluent human umbilical vein endothelial cells and MN collected from healthy donors were stimulated with bacterial lipopolysaccharide, interleukin-1β or tumor necrosis factor-α after incubation with increasing concentrations of resveratrol or quercetin. Results : In both cell types, TF activity induced by any agonist was significantly reduced by resveratrol or quercetin in a dose-dependent fashion. Northern blot analysis indicated that resveratrol and quercetin strongly reduce TF mRNA in both cell types. The inhibition of TF mRNA originated from a reduction in nuclear binding activity of the transacting factor c-Rel/p65, which was induced by the agonists and measured by electromobility shift assay. Western blot analysis revealed that the diminished c-Rel/p65 activity was dependent upon inhibition of degradation of the c-Rel/p65 inhibitory protein IκBα. Conclusions : These results provide a molecular basis which could help explain the protective activity of red wine against cardiovascular disease.     

Suppressive effects of quercetin on hydrogen peroxide-induced caveolin-1 phosphorylation in endothelial cells

Caveolin-1 is a major protein of the caveolae structure in vascular endothelial cell membrane. Phosphorylation of caveolin-1 is one of the initial events leading to exacerbation of vascular permeability caused by oxidative stress. Although quercetin is known to be an anti-atherosclerosis factor that acts as a dietary antioxidant, little is known about its role in the regulation of caveolin-1 phosphorylation. In this study, we investigated the inhibitory effect of quercetin on hydrogen peroxide-induced caveolin-1 phosphorylation in human umbilical vein endothelial cells. Quercetin inhibited caveolin-1 phosphorylation in cells pretreated with quercetin for 24 h and then exposed to hydrogen peroxide. However, quercetin 3-O-β-glucuronide, a conjugated metabolite of quercetin, did not exert this inhibitory effect. Exposure to hydrogen peroxide increased vascular permeability and reduced mRNA expression of the intercellular adhesion protein, vascular endothelial cadherin (VE-cadherin). By contrast, pretreatment with quercetin suppressed the increase in vascular permeability and decreased VE-cadherin expression. These results indicate that deconjugated quercetin can play a role in the prevention of altered vascular permeability under oxidative stress by suppressing caveolin-1 phosphorylation. Thus, dietary quercetin may be beneficial for the maintenance of endothelial cell function.     

Cytotoxic,apoptotic, and sensitization properties of ent‐kaurane‐type diterpenoids from Croton tonkinensis Gagnep on human liver cancer HepG2 and Hep3b cell lines

Human hepatocellular carcinoma (HCC) is the most common type of liver cancer, the second most common cause of death from cancer worldwide. A very poor prognosis and a lack of effective treatments make liver cancer a major public health problem, notably in less developed regions, particularly in eastern Asia. This fully justifies the search of new molecules and therapeutic strategies against HCC. Ent‐kaurane diterpenoids are natural compounds displaying a broad spectrum of potential therapeutic effects including anticancer activity. In this study, we analyzed the pharmacological properties of a family of ent‐kaurane diterpenoids from Croton tonkinensis Gagnep in human HepG2 and Hep3b cell lines, used as cellular reference models for in vitro evaluation of new molecules active on HCC. A structure‐related cytotoxicity was observed against both HCC cell lines, enlighting the role of the 16‐en‐15‐one skeleton of ent‐kaurane diterpenoids. Cytotoxicity was closely correlated to apoptosis, evidenced by concentration‐dependent subG1 cell accumulation, and increased annexin V expression. In addition, subtoxic concentration of ent‐kaurane diterpenoid dramatically enhanced the sensitivity of HCC cells to doxorubicin. All together, our data bring strong support to the potential interest of ent‐kaurane diterpenoids, alone or in combination with a cytotoxic agent, in cancer and more precisely against HCC.     

载紫杉醇聚乳酸聚乙醇酸共聚物纳米粒抑制人肝癌细胞HepG2的作用

背景：临床上应用的紫杉醇注射剂毒性大,过敏反应发生率高。目的：研制载紫杉醇聚乳酸聚乙醇酸共聚物纳米粒,观察其对人肝癌细胞HepG2的抑制及诱导细胞凋亡的作用。方法：采用MTT法检测0,3.125,6.25,12.5,25,50,100mg/L载紫杉醇聚乳酸聚乙醇酸共聚物纳米粒子或紫杉醇作用后人肝癌细胞HepG2的生长;观察25mg/L载紫杉醇聚乳酸聚乙醇酸共聚物纳米粒子或紫杉醇作用后人肝癌细胞HepG2的形态变化,并观察0,12.5,25,50mg/L载紫杉醇聚乳酸聚乙醇酸共聚物纳米粒子作用后细胞的凋亡情况。结果与结论：在3.125-100mg/L质量浓度范围内,载紫杉醇聚乳酸聚乙醇酸共聚物纳米粒子与紫杉醇均能明显抑制HepG2细胞的生长,且载紫杉醇聚乳酸聚乙醇酸共聚物纳米粒子显示出明显的缓释作用,随着作用时间的增加其抑制率显著增加,72h时抑制效果最好,但紫杉醇此现象不明显。载紫杉醇聚乳酸聚乙醇酸共聚物纳米粒子或紫杉醇作用后,细胞出现典型的凋亡形态,且随着载紫杉醇聚乳酸聚乙醇酸共聚物纳米粒子作用时间的增加这一现象更加典型;12.5,25,50mg/L载紫杉醇聚乳酸聚乙醇酸共聚物纳米粒子可明显诱导细胞凋亡,且有明显的量效和时效关系,质量浓度越高、时间越长效果越明显。