Cyclin/Cdks复合物相关调控分子与肿瘤关系的研究进展

细胞周期（cellcycle）是一个高度有序的运转过程，这种高度有序的运转是通过cyclin／Cdks复合物来实现的。Cyclin／Cdks的作用具有时相特异性，在细胞周期的不同阶段，其作用的cyclin／Cdks分子亦不同。Cyclin／Cdks复合物的活性由一个复杂的调控网络进行调控（图1），其中比较重要的调控机制是Cdk的磷酸化状态、Cdk抑制蛋白（CKI）的抑制作用以及cyclin的合成及降解等。细胞周期调控网络的异常与肿瘤的发生发展密切相关，cyclin、Cdks的异常表达、Cdk抑制蛋白的缺失，以及检测点（checkpoint）的异常等都将使细胞周期紊乱，细胞增殖失控，最终发生癌变。2001年的诺贝尔医学和生理学奖授予了发现cyclin和Cdk及其相关分子的科学家，     

p27、cyclin D1与恶性肿瘤

细胞周期调控紊乱是恶性肿瘤发生、发展的主要原因之一,其中,蛋白p27与cyclin D1在细胞周期调控中发挥了重要作用.p27与cyclinD1是细胞周期正负调控因子.p27蛋白在多数肿瘤中低表达或不表达,而cyclinD1蛋白多呈高表达,它们与恶性肿瘤的发生、发展关系密切.目前细胞周期及其调控机制与肿瘤的关系已成为研究热点.     

细胞周期素D1与肿瘤研究进展

肿瘤是一类细胞周期性疾病，细胞生长周期的失调在肿瘤的发生发展中起关键作用。细胞周期素D1(cyclin D1)在细胞周期的正常调控中扮演重要角色，其基因结构、功能的异常与肿瘤发生发展密切相关。现综述cyclin Dl与肿瘤研究的最新进展。     

细胞周期调控及其在肿瘤发生与治疗中的应用

细胞周期素(cyclin)和细胞周期素依赖性激酶(cyclin-dependent kinases,CDK)是细胞周期调控的基本分子。CDK的活性依赖于cyclin的存在,cyclin-CDK复合体周期性装配、激活和降解是驱动细胞周期有序进行的基本分子机制。已经发现cyclin有11种:cyclin A-K,CDK有10种:CDK 1-10。但是在细胞周期过程发挥主要作用的只有:cyclin A、B、D和E,以及CDK1、2、4和6。CDK在大部分细胞中恒定表达,而cyclin的合成与降解仅仅发生在细胞周期的某一时相。cyclin与CDK装配成不同的复合体在细胞周期的不同时相发挥作用,保证细胞周期有序进行。     

细胞周期调控因子与癌发生的关系

近年来 ,有关细胞周期调控机制及其与恶性肿瘤发生的关系研究进展较快。细胞周期调控可分为G1期调控和非G1期调控。在G1期调控中 ,细胞周期蛋白依赖性激酶复合体cyclin CDK激活后 ,通过Rb蛋白和转录因子启动基因转录。p16、p2 1、p15等蛋白通过抑制cyclin CDK的活性而发挥作用。p5 3蛋白和mdm2蛋白协同调节细胞周期活动。其中任何一个环节的变化都可引起细胞周期失控而促使癌发生     

细胞周期素B与白血病

近年的研究发现，调节细胞周期的一些关键因子与肿瘤的发生有密切的关系，这与肿瘤的最基本的特征——增生失控相一致。细胞周期的调控过程是极其复杂和精确的。在细胞周期进程中存在许多的检测点，以判断上一阶段是否正确完成，通过反馈控制确保细胞准确无误地完成分裂。如果反馈控制失效，则可能导致肿瘤的发生。细胞周期的进程主要依靠细胞周期紊(cyclin)，细胞周……     

抑癌基因p16与细胞周期调控

细胞周期是细胞生命活动的基本过程,细胞在周期时相的变迁中进入增殖、分化、衰老和死亡等生理状态。若细胞周期调控异常,细胞将进入病理状态,且与肿瘤的发生也密切相关。参与细胞周期调控的分子主要包括:细胞周期蛋白(cyclin),细胞周期蛋白依赖性激酶(cy-clin-dependentkinase,CDK),磷酸化酶以及细胞周期蛋白依赖性激酶抑制蛋白(CDKinhibitorCKI),这些调节成分组成多条调节途径,通过使Rb磷酸化或去磷酸化构成以Rb为中心的一个复杂网络[1]。CKI通过竞争性结合cyclin或CDK/cyclin复合物,导致cyclin生物活性丧失,最终表现为负调控细胞…     

中药影响乳腺癌细胞周期的研究进展

0引言早在20世纪90年代,已有学者提出肿瘤是一种细胞周期疾病,细胞周期调节紊乱是肿瘤发生的重要环节[1].乳腺癌是女性最常见的恶性肿瘤之一,乳腺癌的发生发展与细胞周期调控因子表达异常密切相关[2].细胞的生命开始于细胞周期,细胞周期的正常运行依赖于精细的调控机制,细胞周期蛋白(cycline)、细胞周期蛋白依赖性激酶(cyclin depengdent kinase,CDK)、细胞周期蛋白依赖性激酶抑制剂(cyclin dependent kinase inhibitor,CKI)三者相互作用,共同参与细胞周期调控,在维持细胞有序的增殖、分裂活动中起重要作用[3,4].     

细胞周期蛋白依赖性激酶与肿瘤关系的研究进展

在生物进化过程中,细胞发展并建立了一系列的精细的调控机制,以确保细胞周期严格有序地交替和各时相依次有序变更。细胞周期蛋白依赖性激酶（CDKs）是细胞周期调节的核心,其与细胞周期蛋白（Cyclins）、细胞周期蛋白依赖性激酶抑制因子（CKIs）等组成细胞周期调控网络系统。早在90年代,人们就提出肿瘤是一种细胞周期疾病,细胞周期中任一环节的抗过度增生的调控机制发生改变,则导致肿瘤的发生。了解CDKs在细胞周期调控中的作用及与肿瘤的关系对认识肿瘤发生和演进、临床诊断及治疗有十分重要的意义。     

HPVl6／18在膀胱癌中表达及其与bFGF、cyclin D1和cyclin E的相关关系

目的：探讨人乳头瘤病毒(HPV)16／18与膀胱癌发病之间关系及其作用机制。方法：应用免疫组化方法检测78例膀胱癌标本和22例正常膀胱组织中HPVl6／18、碱性成纤维细胞生长因子(bFGF)、细胞周期蛋白(cycljn)D1和cyclin E的表达及相关关系。结果：膀胱癌中HPVl6／18阳性率为65．4％，显著高于正常的27．3％；而且与肿瘤病理分级、分期相关，但与肿瘤复发无相关。膀胱癌中HPVl6／18与bFGF及cyclin D1表达之间有显著相关性，但与cyclin E表达之间无显著相关性。结论：HPVl6／18感染参与膀胱癌发病过程，而且通过多途径发挥作用。     

Bacteria and cancer--antagonisms and benefits

There is considerable historical and recent evidence concerning the antagonisms between acute bacterial infections or their toxins and cancer and allied diseases. These data provide renewed incentives to undertake clinical programmes with mixed bacterial vaccines in many countries at the present time.     

VEGF及KDR在大肠腺瘤和腺癌中的表达及意义

目的：探讨VEGF和KDR在大肠腺瘤和大肠腺癌中的表达及临床病理特征的关系。方法：大肠腺瘤和大肠腺癌组织标本各100例,采用免疫组织化学染色法检测VEGF和KDR在标本中的表达情况。结果：VEGF和KDR在大肠腺癌组中的阳性表达明显高于大肠腺瘤组（P〈0.05）;在正常大肠黏膜均未见VEGF和KDR表达的阳性染色;VEGF阳性表达组中KDR的阳性表达率为70%,显著高于VEGF阴性表达组中KDR的阳性表达率16%,两组比较有统计学意义（P〈0.01）。结论：大肠腺癌组织中KDR的表达与肿瘤大小、转移情况、浸润深度密切相关;VEGF和KDR在大肠腺瘤中的表达与患者的年龄、性别及分型均无相关性,而与增生程度相关（P〈0.05）。在大肠腺癌患者中VEGF及KDR表达更高,二者具有协同效应。     

Religiosity and physical and emotional functioning among African American and White colorectal and lung cancer patients

The literature suggests that religiosity helps cope with illness. The present study examined the role of religiosity in functioning among African Americans and Whites with a cancer diagnosis. Patients were recruited from an existing study and mailed a religiosity survey. Participants (N = 269; 36% African American, 56% women) completed the mail survey, and interview data from the larger cohort was utilized in the analysis. Multivariate analyses indicated that in the overall sample religious behaviors were marginally and positively associated with mental health and negatively with depressive symptoms. Among women, religious behaviors were positively associated with mental health and negatively with depressive symptoms. Religiosity was not a predictor of study outcomes for men. Among African Americans, religious behaviors were positively associated with mental health and vitality. Among Whites, religious behaviors were negatively associated with depressive symptoms. These findings suggest a mixed role of religious involvement in cancer outcomes. The current findings may have applied potential in the areas of emotional functioning and depression.     

Genetic polymorphisms of alcohol and aldehyde dehydrogenases and risk for esophageal and head and neck cancers

Alcoholic beverages are causally related to cancer of the oral cavity, pharynx, larynx and esophagus. Ethanol is oxidized to acetaldehyde and then to acetate by alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), both of which have genetic polymorphisms. A review of case-control studies of the effects of ALDH2, ADH2 and ADH3 genotypes shows consistently positive associations between inactive heterozygous ALDH2 and the less-active ADH2 genotypes and the risk for esophageal cancer in East Asian heavy drinkers and this enzyme-related vulnerability may extend to light-to-moderate drinkers. Some studies suggest similar associations with the risk for head and neck cancer in moderate-to-heavy-drinking Japanese. An established carcinogen in experimental animals, acetaldehyde can interact with human DNA. ALDH2-associated cancer susceptibility fits into a scenario in which acetaldehyde plays a critical role in the development of human cancer. Alcohol flushing and drinking behavior may partly explain this carcinogenic effect in carriers of less-active ADH2 genotypes. Whether the ADH3 genotype influences head and neck cancer risk in Western nations is controversial. Professional and public education about risky conditions connected to the ALDH2 and ADH2 genotypes and environmental factors is important in a new strategic approach to the prevention of alcohol-related cancers in East Asians. The use of simple tests to identify inactive ALDH2 on the basis of alcohol flushing responses could benefit many people, by helping them to identify their own cancer risks. Such testing could also help clinicians diagnose esophageal cancer earlier, through the use of endoscopic screening in the high-risk population.     

Religiosity and Physical and Emotional Functioning Among African American and White Colorectal and Lung Cancer Patients

The literature suggests that religiosity helps cope with illness. The present study examined the role of religiosity in functioning among African Americans and Whites with a cancer diagnosis. Patients were recruited from an existing study and mailed a religiosity survey. Participants (N = 269; 36% African American, 56% women) completed the mail survey, and interview data from the larger cohort was utilized in the analysis. Multivariate analyses indicated that in the overall sample religious behaviors were marginally and positively associated with mental health and negatively with depressive symptoms. Among women, religious behaviors were positively associated with mental health and negatively with depressive symptoms. Religiosity was not a predictor of study outcomes for men. Among African Americans, religious behaviors were positively associated with mental health and vitality. Among Whites, religious behaviors were negatively associated with depressive symptoms. These findings suggest a mixed role of religious involvement in cancer outcomes. The current findings may have applied potential in the areas of emotional functioning and depression.     

New and emerging radiosensitizers and radioprotectors

The combination of chemotherapy and radiation has led to clinical breakthroughs in several disease sites, and current work continues to define optimum combinations of proven chemotherapy as well as more recently available, noncytotoxic agents. Administration of systemic therapies allows modulation of radiation response to improve tumor control (radiosensitization) or to prevent normal tissue toxicity (radioprotection). Substantial progress has been made in identifying the targets of standard chemotherapeutic radiation sensitizers and protectors as well as in the introduction of a new generation of molecularly targeted therapies in combination with radiation. We have reviewed the most recent, predominantly early phase clinical trials combining systemic agents with radiation. Although the proof of an improved schedule ultimately needs to come from well-run Phase III trials, the search among schedules could be shortened by the use of surrogate endpoints such as presence of active drug metabolites in the tumor. This has been accomplished only in a few cases and needs to become a more standard part of radiation sensitizer and protector trials.