硒对癌症的预防和临床问题的研究现状

从流行病学、实验室和临床等的研究均表明微量元素硒具有化学防癌的潜力，特别是近来富硒酵母应用于肺癌、肠癌、前列腺癌和肝癌等临床干预试验，表现出硒具有强大的保护作用。本文着重论述了硒化合物发展成为化学防癌药物的作用机制问题，这些机制表现在硒具有抗致癌的生物活性。还讨论了对硒的化学预防试验人群的选择，硒的干预试验，临床应用结果和安全范围的指标等问题。     

血硒与肺癌

硒是谷胱甘肽过氧化物酶（ＧＳＨ－ＰＸ）的组成成分，是人体生命活动所必需的微量元素，本文主要就血硒的流行病学研究、人体硒状况的估价、硒的抗癌机制以及血硒在肺癌诊断和防治中的意义等方面作一概述。     

硒与癌症

硒是人体必需微量元素。流行病学调查表明。土壤硒含量，谷物硒含量。食物硒摄入量及人体血硒水平与多种癌症发病率（死亡率）呈负相关，动物实验证实，适量硒具有抑癌抗癌作用，硒抗癌机理研究及人体干预试验进一步说明硒与癌症关系密切。     

亚硒酸钠通过活性氧(ROS)/谷胱甘肽(GSH)/谷胱甘肽过氧化物酶(GPX4)轴诱导非小细胞肺癌A549细胞铁死亡

硒作为人体必需的微量元素,具有抗癌作用,但其抗癌机制尚不明确,因此,通过探讨亚硒酸钠是否可以通过铁死亡途径抑制肺癌A549细胞增殖及其肺癌A549细胞发生铁死亡的具体机制。通过细胞增殖实验(CCK-8实验)及细胞计数实验评价亚硒酸钠对A549细胞增殖的影响,通过流式细胞术分析亚硒酸钠对肺癌A549细胞内线粒体膜电位(MMP)及活性氧(ROS)水平的影响,通过亚铁离子检测试剂盒检测亚硒酸钠作用后肺癌A549细胞内亚铁离子含量变化,MDA检测试剂盒分析亚硒酸钠作用后肺癌A549细胞内脂质氧化产物丙二醛(MDA)含量,分光光度法分析亚硒酸钠对肺癌A549细胞内谷胱甘肽过氧化物酶4(GPX4)及谷胱甘肽(GSH)的表达影响。研究发现：亚硒酸钠能够显著抑制肺癌A549细胞增殖,且亚硒酸钠抑制肺癌A549细胞的半数抑制率(IC₅₀)为10μmol/L;亚硒酸钠能诱导肺癌A549细胞内ROS过度积累并使细胞内谷胱甘肽耗竭;亚硒酸钠作用后,细胞内线粒体膜电位水平显著降低,MDA含量升高而GPX4蛋白表达下调。研究表明,亚硒酸钠能通过诱导肺癌A549细胞内ROS过度积累,引起细胞内...     

基于硒元素的抗癌药物研究进展

硒是人体必需的一种微量元素,对维持人体正常生理功能起着关键作用,具有广泛的生物学活性,并通过多种机制发挥抗肿瘤作用,缺硒与冠心病、贫血症、关节炎、糖尿病等有着密切的关系。本文对硒的性质、抗肿瘤作用机制、含硒抗肿瘤药物的分类以及有机硒抗肿瘤药物等方面进行了介绍,以期提高人们对含硒抗肿瘤药物的准确认识,促进含硒抗肿瘤药物的...     

硒蛋白的抗氧化性研究与第21个氨基酸的发现

硒是人体必需的微量元素,以硒代半胱氨酸(Sec)的形式存在于蛋白质中作为硒酶的活性中心发挥作用,其生物功能主要是抗氧化。由于硒与人体健康具有十分密切的关系,所以硒蛋白的研究有着重要的理论和实际意义。本文以第一个硒蛋白细胞谷胱甘肽过氧化物酶为例,结合作者自己的工作,重点对该硒酶的结构、催化机制和模拟进行了综述,并就TGA编码Sec致第21个氨基酸的发现以及基于硒代半胱氨酸插入元件(SECIS)的特征寻找新硒蛋白的研究进展进行了介绍。     

硒对汞毒性的拮抗作用及机理

硒是一种生物必需微量元素,而汞是剧毒重金属元素之一.硒、汞相互作用一直备受国内外研究者关注.本文系统概括了人体、动植物及生态系统中硒、汞相互作用的研究进展,探讨了硒、汞相互作用的机制,以期为利用硒降低汞的毒性提供理论基础,为降低汞对人体及环境健康的危害和国家汞污染治理提供技术支持.     

微量元素硒对眼科疾病防治的研究进展

硒是人体必需微量营养元素,在人体代谢过程中参与多种代谢活动,参与维持眼睛正常的生理生化功能,微量元素硒缺乏会引起眼睛的生理生化功能紊乱,引起眼科疾病如老年性白内障等,适当补硒可以激活体液和细胞免疫调节能力.参考相关文献综述了硒的作用机制及其对眼科疾病防治的进展.     

硒形态分析研究进展

硒是人体必需的微量元素,许多疾病跟体内硒缺乏或者硒中毒有关。由于不同形态硒化合物的功效及其毒性各不同,因此准确地定性定量分析不同形态和价态的硒对保障人体安全及健康具有重要意义。本文对近年来有关学者在硒形态检测上常用的提取、分离、测定技术进行综述介绍。     

微波消解-原子荧光光谱法分析肺癌患者全血中硒

目的探讨肺癌患者血样中硒含量的变化。方法采集肺癌组和对照组血样,用硝酸、过氧化氢混合液微波消解样品,采用原子荧光光谱法测定血样中硒的含量。结果肺癌组和对照组硒平均质量浓度分别为0.087、0.123 mg/L。结论肺癌患者血样硒含量明显降低,缺硒可能是导致肺癌高发的重要因素。     

硒抗大鼠肺纤维化的实验研究

为了解硒对肺纤维化的预防作用，采用油酸大鼠尾静脉注射制作肺纤维化模型，观察了硒对损伤肺组织中中性粒细胞聚集及氧自由基的干预作用。结果显示，硒可通过抑制中性粒细胞而减少氧自由基的产生，进而控制肺泡炎变、渗出，减轻炎性因子对肺脏的慢性刺激，预防肺纤维化，因此硒对油酸所致的肺纤维化有一定的预防作用。     

微量元素硒在肿瘤防治中的作用及应用前景

硒作为人类必需的必需元素，人们对其重要性的认识日益提高，已经将将缺硒与增加癌症风险联系在一起。本文就硒在肿瘤防治中的可能作用及其应用进展，从流行病学调查、实验室和人群试验三个方面作一综述。尽管对其作用仍然存在不同观点的争论，但多数报道提示硒在抗癌领域有良好的应用前景。     

Complementary use of molecular and element-specific mass spectrometry for identification of selenium compounds related to human selenium metabolism

The aim of this paper is to give an overview of analytical data on the identification of selenium compounds in biological samples with relevance for selenium metabolism. Only studies applying the combination of element-specific inductively coupled plasma mass spectrometry as well as molecular electrospray mass spectrometry detection have been included. Hence, selenium compounds are only considered identified if molecular mass spectra obtained by analysis of the authentic biological sample have been provided. Selenium compounds identified in selenium-accumulating plants and yeast are included, as extracts from such plants and yeast have been widely used for examination of the cancer-preventive effect of selenium in cell lines, animal models and human intervention trials. Hence, these selenium compounds are available for absorption and further metabolism. Identification of selenium metabolites in simulated gastric and intestinal juice, intestinal epithelial tissue, liver and urine is described. Hence, selenium metabolites identified in relation to absorption, metabolism and excretion are included.     

The determination of selenium concentration in blood and tumour tissues of breast cancer patients in Syria using instrumental neutron activation analysis

The aim of this study was to investigate the relationship of selenium concentration in blood components and tumour tissues of breast cancer patients and healthy volunteers (control), in Syria, using instrumental neutron activation analysis (INAA). Red blood cells and serum selenium concentrations were determined in 50 healthy volunteers aged 25-70 years and 70 breast cancer patients aged 25-84 years. Selenium levels were also measured in malignant and adjacent normal tissues from breast cancer patients. The accuracy of the analysis was evaluated by co-analyses of international reference materials. The results showed that selenium concentration in serum and RBC was significantly lower among breast cancer patients compared to healthy volunteers (P<0.001). The results also showed that the selenium concentration was significantly higher in the cancer tissues compared to adjacent normal tissues (P<0.001). We conclude that there is a good indication for selenium deviation in blood and malignant tissue of breast cancer patients compared to that of healthy volunteers. This revised version was published online in July 2006 with corrections to the Cover Date.     

Anti‐cancer potential of selenium‐ and tellurium‐containing species: opportunities abound!

An overview highlighting the anti‐cancer potential of (bio‐essential) selenium‐ and tellurium‐containing species, with an emphasis on biological targets and mechanisms of action, is presented. Studies thus far have focused on selenium(II) compounds (along with – to a lesser extent – inorganic selenium and selenium nanoparticles) which often successfully exploit the inherent anti‐oxidizing ability of selenium. Significantly less work has been conducted in developing anti‐cancer tellurium compounds, yet two tellurium(IV) species are proven, clinically, as anti‐cancer agents. Given the prevalence of the disease and the accumulated insights into mechanisms of action, the continued development of selenium‐ and tellurium‐containing molecules is an area deserving greater attention. Copyright © 2012 John Wiley & Sons, Ltd.     

硒补充：防治艾滋病的有效新策略

从以下四方面：（1）低硒——引发艾滋病的基础性因素,（2）病毒复制——进一步消耗体内的硒,（3）硒水平——艾滋病结局的独立预测指标,（4）硒补充——防治艾滋病的有效新策略,详细论述了硒在艾滋病发生、发展和结局中的作用,列举了硒剂防艾滋病干预试验的某些初步结果。如能采用理想的“硒”,并在随机化、大样本量的对照试验中得到进一步证实,则硒补充作为一种简单易行、消费得起的干预措施,可能具有公共健康效益。     

Long-term selenium status in humans

The association of sub-optimal selenium status with increased riskfactors for some cancers has been reported in two recent epidemiological studies.In both studies the same threshold in selenium status was observed, belowwhich, cancer incidence increased. To assess the use of nails as a biologicmonitor to measure the long-term selenium status, an eight-year longitudinalstudy was undertaken with a group of 11 adult subjects, 5 women and 6 men.Selenium has been measured by instrumental neutron activation analysis. Differencesbetween fingernails and toenails will be discussed. In addition, the resultswill be discussed in the context of the long-term stability of the nail monitorto measure selenium status during those periods when selenium determinantsare static; and the changes that occur as a result of selenium supplementation.