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复方苦参注射液协同索拉非尼提高晚期肝细胞癌应答

复方苦参注射液协同索拉非尼提高晚期肝细胞癌应答

复方苦参注射液协同索拉非尼提高晚期肝细胞癌应答李先晨1,徐秋燕2,盛文飞2,李栋梁3,吴庆庆1,陶忠义1*(1. 安徽医科大学附属六安医院药学部,安徽六安 237000;2. 安徽医科大学附属六安医院肿瘤内科,安徽六安237000;3. 安徽医科大学附属六安医院普外科,安徽六安 237000)摘要目的:采用临床队列、网络药理学框架及分子对接技术阐明复方苦参注射液(CKI)协同索拉非尼治疗晚期肝细胞癌(HCC)的物质基础和分子机制。

方法:依据入组标准选取安徽医科大学附属六安医院2019年7月至2022年6月间治疗的134例晚期HCC 患者,其中CKI-索拉非尼组和索拉非尼组各67例。

分析两组患者应答率和总体生存率。

通过网络药理学框架结合中药系统药理学数据库与分析平台及GeneCards、OMIM,PharmGkb、TTD 和 DrugBank 数据库鉴定CKI 治疗晚期HCC 的靶基因。

通过酶联免疫吸附测定验证两组患者治疗前后FBJ 骨髓瘤病毒癌基因同源物(FOS)和表皮生长因子受体(EGFR)表达。

结果:CKI-索拉非尼组患者治疗应答率和生存率均高于索拉非尼组患者(应答率:74.6%∶66.2%,P =0.032;生存率:38.8%∶23.9%,P =0.013)。

FOS 和EGFR 是CKI 治疗晚期HCC 的核心靶基因。

治疗3个月后,CKI-索拉非尼组患者外周血FOS 和EGFR 浓度较索拉非尼组患者显著降低[FOS 浓度:(8.41±2.17)ng/ml ∶(9.85±2.47)ng/ml,P <0.001;EGFR 浓度:(5.47±2.14)ng/ml ∶(6.28±2.04)ng/ml,P =0.027]。

分子对接模型证实槲皮素能与FOS 和EGFR 相互作用,结合能分别为-8.2 kcal/mol 和-7.9 kcal/mol。

结论:CKI 协同索拉非尼提高晚期HCC 患者应答率和生存率,其FOS 和EGFR 是介导其应答的潜在机制。

自体脂肪间充质干细胞抗衰原理

自体脂肪间充质干细胞抗衰原理

自体脂肪间充质干细胞抗衰原理
自体脂肪间充质干细胞(ADSCs)是一种来源于脂肪组织的干细胞,具有多向分化潜能和自我更新能力。

它们被认为具有抗衰老的
潜力,主要原理如下:
1. 分泌生长因子,ADSCs可以分泌多种生长因子,如表皮生长
因子(EGF)、基本成长因子(bFGF)和血管内皮生长因子(VEGF),这些生长因子可以促进细胞增殖、修复受损组织和促进血管生成,
从而减缓皮肤老化过程。

2. 抗氧化作用,ADSCs具有显著的抗氧化能力,可以中和自由基,减少氧化应激对皮肤造成的损害,延缓皮肤衰老。

3. 促进胶原蛋白生成,ADSCs可以促进胶原蛋白的生成,胶原
蛋白是皮肤的重要成分,能够增加皮肤的弹性和紧致度,减少皱纹
的形成。

4. 免疫调节作用,ADSCs可以调节免疫反应,减少炎症反应,
改善皮肤的免疫环境,有助于减缓皮肤老化的进程。

总的来说,自体脂肪间充质干细胞通过分泌生长因子、抗氧化、促进胶原蛋白生成和免疫调节等多种途径,可以对抗皮肤衰老,改
善皮肤质地,减少皱纹和松弛,使皮肤恢复年轻、光滑和有弹性。

这些原理为其在抗衰老领域的应用提供了科学依据。

认识自体活细胞

认识自体活细胞

关于自体adipose活细胞丰胸自体adipose活细胞到底是什么呢,它又有怎样神奇的效果?自体细胞(Autogenous adipose tissue)是具有自我更新能力(self-renewal)的高质量复制细胞,经过重点实验室提纯,它可以分化成细胞等多种细胞功能。

根据自体细胞所处发育阶段分为胚胎活细胞(embryonic living cell,ES细胞)和成体活细胞(somatic stem Cell)。

根据自体细胞的发育潜能分为三类:全能活细胞(totipotent living cell,TSC)、多能活细胞(pluripotent living cell)和单能活细胞(unipotent living cell)。

活细胞(Living cells)是一种未充分分化,尚不成熟的细胞,具有自我更新和存活的潜在功能。

自体adipose活细胞丰胸,以大腿、臀部或腹部细胞里提取有限的母细胞,经GMP 生物实验室提纯、利用母细胞中大量间质细胞体内多重分化的潜力,将完整的细胞复制分化大量的细胞与多种生长因子配比,回注到乳房,由此产生的血管生长因子(VEGF)促进了大量毛细血管的生成和微循环的建立,因此解决了细胞进入体内后的营养供给,并不断刺激乳房细胞自我更新与修复。

中国医学科学院生物化学教授、博士生导师袁建刚曾表示,纤连蛋白在肌肤细胞修复过程中,不仅完成了传统生长因子、活性因子对细胞的促活功能及胶原肽、玻尿酸等物质的细胞营养功能,更重要的是纤连蛋白实现了让各层细胞有序排列、肌肤纤维有序生长的目的,最终达到自体细胞再生性修复的功效!一个简单的纤连蛋白就可以调动胶原蛋白、纤维蛋白、胶原肽、透明质酸、玻尿酸等物质,达到自体美容丰胸的功效!纤连蛋白能够激活细胞、迁移细胞、刺激细胞、滋养细胞,从而达到恢复肌肤弹性,消除肌肤皱纹,使肌肤更加细嫩、光滑,调节水油平衡,自体细胞经实验室提纯净化后在体内能释放出一种适合细胞生长的酶并由血管生长因子(PDGF)促进为循环形成,能解决移植细胞活细胞营养供给问题。

硫辛酸注射液联合胰激肽原酶肠溶片对DPN_的临床疗效及生存质量的影响

硫辛酸注射液联合胰激肽原酶肠溶片对DPN_的临床疗效及生存质量的影响

DOI:10.16658/ki.1672-4062.2024.01.174硫辛酸注射液联合胰激肽原酶肠溶片对DPN的临床疗效及生存质量的影响王莉,朱海峰濉溪县中医医院内分泌科,安徽淮北235100[摘要]目的探讨硫辛酸注射液联合胰激肽原酶肠溶片对2型糖尿病周围神经病变(Diabetic Peripheral Neu⁃ropathy, DPN)患者的临床疗效、生存质量及安全性的影响。

方法选取2021年2月—2022年4月濉溪县中医医院60名DPN患者作为研究对象。

通过随机数表法分为两组,每组30例。

对照组采用常规治疗,观察组在对照组基础上加用硫辛酸注射液和胰激肽原酶肠溶片治疗。

比较两组患者的神经病变评分、神经电生理指标、生存质量评分、安全性指标和不良反应发生率。

结果治疗后,观察组神经病变评分(6.2±0.9)分低于对照组(7.6±1.1)分,差异有统计学意义(t=5.438,P<0.05);观察组神经电生理指标、生存质量评分、安全性指标均优于对照组,差异有统计学意义(P均<0.05);两组患者不良反应发生率比较,差异无统计学意义(P>0.05)。

结论硫辛酸注射液联合胰激肽原酶肠溶片对DPN患者有良好的临床疗效,能够改善神经功能、改善神经电生理指标、提高生存质量,且安全性高。

[关键词] 硫辛酸注射液;胰激肽原酶肠溶片;2型糖尿病周围神经病变;临床疗效[中图分类号] R587.2 [文献标识码] A [文章编号] 1672-4062(2024)01(a)-0174-05Effect of Lipoic Acid Injection Combined with Pancreatic Kininogenase Enteric-coated Tablets on Clinical Efficacy and Quality of Survival in DPN WANG Li, ZHU HaifengDepartment of Endocrinology, Suixi County Hospital of Traditional Chinese Medicine, Huaibei, Anhui Province, 235100 China[Abstract] Objective To investigate the effects of lipoic acid injection combined with pancreatic kininogenase enteric-coated tablets on the clinical efficacy, quality of survival and safety of patients with type 2 diabetic peripheral neuropathy (DPN). Methods 60 DPN patients admitted to Suixi County Hospital of Traditional Chinese Medicine from February 2021 to April 2022 were selected as the study objects. They were divided into two groups with 30 cases in each group by random number table method. The control group received conventional treatment, and the observation group was treated with lipoic acid injection and pancreatic kininogenase enteric-coated tablets on the basis of control group. Neuropathy score, neuroelectrophysiological index, quality of life score, safety index and incidence of adverse reactions were compared between the two groups. Results After treatment, the neuropathy score of observation group (6.2±0.9) points was lower than that of control group (7.6±1.1) points, and the difference was statistically significant (t= 5.438, P<0.05). Neuroelectrophysiological indexes, quality of survival scores and safety indexes of the observation group were better than those of the control group, and the differences were statistically significant (all P<0.05). There was no significant difference in the incidence of adverse reactions between the two groups (P>0.05). Conclusion Li⁃[作者简介]王莉(1982-),女,本科,主治医生,研究方向为糖尿病周围神经病变。

博辉瑞进打造“生命黑科技”

博辉瑞进打造“生命黑科技”

博辉瑞进打造“生命黑科技”作者:暂无来源:《经理人》 2019年第9期博辉瑞进是一家致力于为外科手术和修复提供先进的全面解决方案,推动外科临床革新。

拥有自主知识产权的再生医学材料、植入性组织修复器械、智能化微创手术器械等平台性技术。

该公司自主研发的核心产品和技术——非交联细胞外基质源生物材料(SIS材料),是中国再生医学中的“黑科技”。

文 / 张艺琼很多科幻电影里都有这样的情节:主角身体受到严重创伤,在先进医疗技术帮助下,患者的创处很快痊愈,伤口也恢复如初。

在医学科技高速发展的今天,这种美好遐想正在逐步照进现实,这一切都源于一项可以改变人类命运和未来的学科—再生医学(regenerative medicine)。

美国生物学家、诺贝尔奖得主吉尔伯特曾预言:“用不了50年,人类将能够培育出人体所有器官。

”随着干细胞、组织工程等研究的不断深入,“再生医学”这门新型学科开始引领一场影响深远的医学革命。

根据公开信息,中国在科技方面的研发开支额度已经从1996年的59亿美元增长到了今天的440亿美元。

其中,中国再生医学研发资助的约78%被用于产品开发,另外约16.8%用于应用研究。

中国已经开发出了大量灵长类动物群用于临床前测试,而且一系列疗法开始了临床测试。

根据MRC(Myofunctional Research Center)认为,中国对临床应用的迫切要求—这让它可以迅速产生新的科学知识—是以损害一些基础研究为代价的,这些基础研究旨在克服控制干细胞行为和分化等技术挑战。

另外,中国研发预算只有5.2%分配给了基础研究,相比之下,日本、韩国和美国的比例是13%到19%。

即便是那些分配给支持“战略基础研究”的基础研究资助也被设计成鼓励应用。

在再生医学方面要取得卓越成就,中国各科研机构和商业企业,面临的难度不小。

再生医学“黑科技”“再生医学是一门对于生命探索的科学,作为一名生物科研工作者,就是把不可能变为可能。

”北京博辉瑞进生物科技有限公司(以下简称“博辉瑞进”)董事长赵博如是说。

干细胞理论英语作文

干细胞理论英语作文

Stem Cell Theory: Unlocking the Potential ofRegenerative MedicineStem cells, the building blocks of life, have captured the imagination of scientists and researchers worldwide. Their unique ability to transform into specialized cells offers unprecedented opportunities in the field of regenerative medicine. By harnessing the power of stem cells, we can potentially revolutionize the treatment of various diseases and injuries, leading to significant improvements in patient outcomes.The fundamental concept of stem cell theory is based on the plasticity and multipotency of these cells. Plasticity refers to the ability of stem cells to change theiridentity and become different types of cells, while multipotency refers to their capacity to generate multiple cell lineages. This versatility makes stem cells an ideal candidate for tissue regeneration and repair.One of the most promising applications of stem cell therapy is in the treatment of degenerative diseases. These chronic conditions, such as Parkinson's disease and Alzheimer's disease, are caused by the gradual loss ofspecific cell types in the brain. By transplanting stemcells into the affected areas, we can potentially restore lost neural function and improve patient quality of life. Similarly, stem cell therapy could also be used to treat injuries to the spinal cord or other parts of the nervous system.Another exciting area of research is the use of stem cells in regenerative dentistry. Dental implants and other surgical procedures can be highly invasive and painful. However, by using stem cells to regenerate dental tissue,we can potentially avoid these invasive procedures and provide patients with a more comfortable and effective treatment option.In addition to these therapeutic applications, stemcells also play a crucial role in basic biological research. By studying the behavior and interactions of stem cells, we can gain a deeper understanding of the fundamentalprocesses of cell development and tissue formation. This knowledge can, in turn, lead to the discovery of new drugs and therapies for a wide range of diseases.However, the promise of stem cell therapy is not without its challenges. One of the main obstacles is the ethical debate surrounding the use of embryonic stem cells. The extraction of these cells requires the destruction of embryos, which raises ethical concerns among many individuals and groups. To address this issue, researchers have been exploring alternative sources of stem cells, such as adult stem cells and induced pluripotent stem cells (iPSCs). These cells offer similar therapeutic potential without the ethical implications associated with embryonic stem cells.Moreover, the technical challenges of stem cell therapy must also be overcome. Transplanting stem cells into the body and ensuring their survival, integration, and differentiation into the desired cell type is a complex process that requires meticulous planning and execution. Researchers are constantly refining their techniques and developing new methods to improve the efficiency and safety of stem cell transplantation.Despite these challenges, the future of stem cell therapy remains bright. With the continued advancements instem cell research and technology, we can expect to see more breakthroughs in the field of regenerative medicine. From treating chronic diseases to regenerating damaged tissues, stem cells hold the key to unlocking new frontiers in healthcare.**干细胞理论:解锁再生医学的潜力**干细胞,作为生命的基石,已经激发了全世界科学家和研究者的想象力。

细胞程序性死亡配体1表位肽疫苗的设计及抗肿瘤活性

细胞程序性死亡配体1表位肽疫苗的设计及抗肿瘤活性

学 报Journal of China Pharmaceutical University 2023,54(2):245 - 254245细胞程序性死亡配体1表位肽疫苗的设计及抗肿瘤活性邵世帅,段树康,田浤,姚文兵,高向东*(中国药科大学生命科学与技术学院江苏省生物药物成药性研究重点实验室,南京 211198)摘 要 目前已有多款细胞程序性死亡受体1(PD-1)和其配体(PD-L1)免疫检查点阻断抗体用于临床治疗,但只有部分患者表现出临床反应,因此需要一种替代的肿瘤免疫治疗策略。

以PD-L1为靶点的治疗性肿瘤疫苗是一种有意义的尝试。

本研究设计了以PD-L1为靶点的表位肽疫苗,然后基于人源化免疫系统(HIS)小鼠模型筛选,具有免疫原性的PD-L1表位肽,进一步研究其抗肿瘤活性。

结果显示,设计并筛选得到的PD-L1-B1表位肽疫苗不仅成功诱导了PD-L1特异性的体液免疫和细胞免疫,还表现出抗肿瘤活性。

此外,免疫治疗还增加了肿瘤的T淋巴细胞浸润,重塑了肿瘤免疫抑制微环境。

综上所述,PD-L1-B1表位肽疫苗表现出强效的抗肿瘤活性,对PD-1/PD-L1阻断不敏感的患者可能是一种有效的替代免疫治疗策略。

关键词肿瘤免疫;免疫检查点;PD-L1;表位肽疫苗中图分类号R73-3 文献标志码 A 文章编号1000 -5048(2023)02 -0245 -10doi:10.11665/j.issn.1000 -5048.2023022803引用本文邵世帅,段树康,田浤,等.细胞程序性死亡配体1表位肽疫苗的设计及抗肿瘤活性[J].中国药科大学学报,2023,54(2):245–254.Cite this article as:SHAO Shishuai,DUAN Shukang,TIAN Hong,et al. Design and antitumor activity of programmed cell death ligand 1 epitope peptide vaccine[J].J China Pharm Univ,2023,54(2):245–254.Design and antitumor activity of programmed cell death ligand 1 epitope peptide vaccineSHAO Shishuai, DUAN Shukang, TIAN Hong, YAO Wenbing, GAO Xiangdong*Jiangsu Provincial Key Laboratory of Druggability of Biopharmaceuticals, School of Life Science and Technology, China Pharmaceu⁃tical University, Nanjing 211198, ChinaAbstract Several programmed cell death protein 1 (PD-1) or its ligand (PD-L1) immune checkpoint blocking antibodies are available for clinical treatment, but only some patients show clinical response, so an alternative strategy for tumor immunotherapy is needed.A therapeutic tumor vaccine targeting PD-L1 is a meaningful attempt.In this study, we designed an epitope peptide vaccine targeting PD-L1, and then screened the immuno‑genic PD-L1 epitope peptide based on the humanized immune system (HIS) mouse model and further investigated its anti-tumor activity.The results show that the designed and screened PD-L1-B1 epitope peptide vaccine not only successfully induced PD-L1-specific humoral and cellular immunity, but also exhibit anti-tumor activity.In addi‑tion, immunotherapy increased T-lymphocyte infiltration of tumors and reshaped the tumor immunosuppressive microenvironment.In conclusion, PD-L1-B1 epitope peptide vaccine exhibits potent anti-tumor activity and may be an effective alternative immunotherapeutic strategy for patients insensitive to PD-1/PD-L1 blockade.Key words tumor immunity; immune checkpoint; PD-L1; epitope peptide vaccineThis study was supported by the National Natural Science Foundation of China (No.82073754, No.81973222); and the Key Research and Development Program of Xinjiang Uygur Autonomous Region (No.2020B03003)收稿日期2023-02-28 *通信作者Tel:134****2857E-mail:1019830864@基金项目国家自然科学基金资助项目(No.82073754,No.81973222);新疆维吾尔自治区重点研发计划(No.2020B03003)学 报 Journal of China Pharmaceutical University 2023,54(2):245 - 254第54 卷免疫检查点阻断(ICB )疗法在癌症治疗方面取得了前所未有的进展,极大地改变了肿瘤治疗策略[1-2]。

细胞蛇的研究进展

细胞蛇的研究进展

2007年,英国牛津大学的刘骥陇等在研究果蝇U 小体和P 小体(U 小体和P 小体是真核生物细胞质中的无膜细胞器)的功能关系时,用4种针对Cup (P 小体中的一种蛋白质)的抗体,对雌性果蝇的卵巢组织进行免疫组织化学染色,染色结果除了预期标记上的P 小体外,还标记出了长条形的丝状结构[1]。

这种结构的形状和数量与纤毛很相似,导致当时以为在果蝇中找到了有纤毛的新细胞类型。

但后来的一系列实验表明,该结构与纤毛没有关系,于是将其命名为“细胞蛇”。

最初是抗Cup 抗体不纯产生假象,意外发现的细胞蛇,而采用亲和层析纯化后的抗Cup 抗体无法再DOI:10.16605/ki.1007-7847.2020.10.0258细胞蛇的研究进展收稿日期:2020-10-22;修回日期:2020-11-19;网络首发日期:2021-07-27基金项目:宁夏自然科学基金项目(2020AAC03179);国家自然科学基金资助项目(31560329)作者简介:李欣玲(1999—),女,广西贵港人,学生;*通信作者:俞晓丽(1984—),女,宁夏银川人,博士,副教授,主要从事干细胞与生殖生物学研究,E-mail:********************。

李欣玲,张樱馨,李进兰,潘文鑫,王彦凤,杨丽蓉,王通,俞晓丽*(宁夏医科大学生育力保持教育部重点实验室临床医学院基础医学院,中国宁夏银川750000)摘要:细胞蛇是近年来细胞生物学研究的热门方向之一,由于其在细胞的增殖、代谢和发育上具有一定的生物学功能,因此,对一些疾病如癌症等的临床诊断或治疗具有一定的指导意义。

细胞蛇是由三磷酸胞苷合成酶(cytidine triphosphate synthetase,CTPS)聚合而成的无膜细胞器,其形成过程及功能在不同类型的细胞中不尽相同。

例如:细胞蛇能促进癌细胞增殖,并使患者病情恶化;过表达的细胞蛇可抑制神经干细胞增殖,影响大脑皮层发育;在卵泡细胞中,细胞蛇相当于CTPS 的存储库,在卵子发生过程起到促进细胞增殖和代谢的作用。

基质胶 基底膜提取物

基质胶 基底膜提取物

基质胶(Matrix Gel,通常指Matrigel)是一种来源于小鼠肿瘤细胞系Engelbreth-Holm-Swarm(EHS)的胞外基质提取物,它是天然的基底膜基质成分的高度纯化的重组产品。

基质胶中含有丰富的基底膜相关的蛋白质和其他生物活性分子,主要包括但不限于:
1. **层粘连蛋白(Laminin)**:这是一种重要的细胞外基质蛋白,参与细胞粘附、迁移、分化和增殖。

2. **Ⅳ型胶原(Collagen IV)**:是构成基底膜结构的主要成分之一,为细胞提供了支撑和锚定位点。

3. **巢蛋白(Nidogen)**:在基底膜中起到连接其他组分的作用,有助于构建稳定的基底膜网络。

4. **硫酸乙酰肝素蛋白聚糖(Heparan Sulfate Proteoglycans, HSPG)**:这类复合糖蛋白带有硫酸乙酰肝素链,参与细胞与基质之间的相互作用、生长因子的结合与调节等过程。

5. **生长因子**:如转化生长因子-β(TGF-β)、表皮生长因子(EGF)、胰岛素样生长因子(IGF)以及纤维母细胞生长因子(FGF)等,这些生长因子在细胞增殖、分化和迁移中起到关键调控作用。

基质胶在实验室研究中有广泛的应用,特别是在体外细胞培养中模拟体内细胞的微环境,它可以自发地在室温下凝固形成三维网状结构,这对于细胞行为学、药物筛选、组织工程、类器官培养以及癌症研究等方面都极为重要。

通过使用基质胶,研究人员能够在二维细胞培养的基础上创建更加接近体内生理条件的三维细胞培养模型。

lyfgenia的原理

lyfgenia的原理

lyfgenia的原理
Lyfgenia疗法的原理,是利用一种慢病毒载体,将改良后的基因功能“拷贝”,再将“副本”“粘贴”到患者自身的造血干细胞中,使其产生抵抗血红细胞镰刀化的血红蛋白。

这种疗法主要用于治疗镰状细胞病。

镰状细胞病的病因是基因突变,导致血红蛋白易粘连,从正常的扁圆形变为坚硬的镰刀状,进而堵塞血管,造成严重疼痛,甚至形成血栓。

Lyfgenia疗法通过增加胎儿血红蛋白(HbF)的产生,来防止红细胞镰状化。

需要注意的是,这种疗法距离真正获得大面积推广应用还有不少挑战。

若你想了解更多Lyfgenia疗法的内容,建议咨询专业医师。

凝血因子ⅷ 作用机制

凝血因子ⅷ 作用机制

凝血因子ⅷ作用机制摘要:一、凝血因子VIII 的概述二、凝血因子VIII 的作用机制三、凝血因子VIII 的适应症和禁忌四、凝血因子VIII 的注意事项五、凝血因子VIII 的贮藏方式正文:一、凝血因子VIII 的概述凝血因子VIII,又称人凝血因子VIII,是一种在人体内参与凝血过程的重要蛋白质。

凝血因子VIII 是由肝脏合成的,其主要作用是纠正凝血功能障碍,对预防和治疗甲型血友病及手术后出血等疾病具有重要意义。

二、凝血因子VIII 的作用机制凝血因子VIII 的作用机制主要涉及以下几个方面:1.凝血因子VIII 能够激活因子IX,从而激活凝血因子X,促进凝血过程的进行;2.凝血因子VIII 能够抑制因子Xa 的活性,避免凝血过程过度激活,保证凝血的平衡;3.凝血因子VIII 还能够增强血管内皮细胞的通透性,促进凝血因子的吸附和激活。

三、凝血因子VIII 的适应症和禁忌凝血因子VIII 主要用于预防和治疗甲型血友病及手术后出血等疾病。

然而,对于已知对制剂的任何成份有超敏反应史的患者和已知对仓鼠蛋白有超敏反应史的患者,凝血因子VIII 是禁忌的。

四、凝血因子VIII 的注意事项在使用凝血因子VIII 时,应注意以下几点:1.药物在使用前需要预热,温度应在27 度至35 度左右。

预热后药物内的晶体可以完全溶解,轻轻摇动可促进药物分解。

药物溶解后1 小时内需要输完。

2.注射时需要注意观察药物是否起到了泡沫的作用。

3.用药后可能会出现头晕、头痛、恶心等不良反应,或是皮肤瘙痒等症状。

五、凝血因子VIII 的贮藏方式凝血因子VIII 应在2~8 摄氏度的环境中避光保存和运输,禁止冷冻。

基因修饰的间充质干细胞提取物,提取方法及在皮肤紧致和抗衰老方面的应用

基因修饰的间充质干细胞提取物,提取方法及在皮肤紧致和抗衰老方面的应用

基因修饰的间充质干细胞提取物,提取方法及在皮肤紧致和抗衰老方
面的应用
基因修饰的间充质干细胞提取物是一种具有生物活性成分的细
胞培养物,其主要成分包括细胞因子、生长因子和其他蛋白质等。

它能够促进细胞增殖、减少细胞凋亡、改善细胞外基质的合成和分泌等作用,从而在皮肤紧致和抗衰老方面发挥重要作用。

以下是基因修饰的间充质干细胞提取物的制备方法:
1. 提取间充质干细胞:将人体脂肪组织或者骨髓等含有间充质
干细胞的组织进行提取和分离,然后通过特定的培养条件让细胞扩增。

2. 基因修饰:通过基因工程技术对间充质干细胞进行基因修饰,使得细胞可以分泌更多的生长因子和细胞因子。

3. 细胞培养和提取物制备:将经过基因修饰的间充质干细胞进
行培养,收集培养上清液并进行精细的提取和纯化,最终得到基因修饰的间充质干细胞提取物。

在皮肤紧致和抗衰老方面,基因修饰的间充质干细胞提取物可以通过多种途径进行应用,例如:
1. 外敷:将基因修饰的间充质干细胞提取物添加到面膜、精华
液等化妆品中,可以直接涂抹于皮肤表面,从而改善皮肤的弹性和紧致度。

2. 注射:将基因修饰的间充质干细胞提取物注射到皮下或者真
皮层,可以刺激皮肤细胞的再生和修复,从而达到抗衰老的效果。

3. 氧气喷雾:将基因修饰的间充质干细胞提取物转化为微小颗
粒并与氧气混合后喷洒于皮肤表面,能够促进皮肤代谢和血液循环,增加皮肤细胞的活力和健康程度。

cell adhension molecule名词解释

cell adhension molecule名词解释

cell adhension molecule名词解释嘿,你知道吗,cell adhension molecule 呀,那可是个超级重要的东西呢!就好比是一群小伙伴手牵手一起玩耍,cell adhension molecule就是让细胞们能紧紧“牵住”彼此的那个关键角色呀!你想想看,细胞们在我们身体里可不能乱跑乱撞吧,它们得有秩序地待在该在的地方,完成各自的任务。

cell adhension molecule 就像是细胞之间的“胶水”,把它们牢牢地粘在一起。

比如说,在我们的皮肤组织里,cell adhension molecule 就让那些皮肤细胞紧密相连,形成一道坚固的防线,保护我们的身体不受外界侵害。

这难道不神奇吗?再看看我们的器官,它们之所以能够稳定地存在和运作,cell adhension molecule 也是功不可没呀!没有它,器官可能就会变得七零八落的,那可就糟糕啦!细胞之间的这种“粘连”可不只是简单地靠在一起哦,它还能传递信号呢!就好像小伙伴之间互相打暗号一样。

“嘿,这边情况怎么样啦?”“一切正常!”通过 cell adhension molecule,细胞们能更好地协调合作,共同为我们的身体服务。

而且哦,不同类型的 cell adhension molecule 还有不同的作用呢!有的负责让细胞紧密结合,有的则在细胞迁移等过程中发挥重要作用。

这就好像不同的工具,各有各的专长。

总之啊,cell adhension molecule 虽然我们看不见摸不着,但它对我们身体的正常运转真的是至关重要呢!它就是细胞世界里的那个神奇“胶水”,让一切都变得有序又和谐。

所以说,可别小瞧了这个小小的cell adhension molecule 呀!。

matrigel成胶原理

matrigel成胶原理

matrigel成胶原理Matrigel是一种由基质蛋白质组成的生物活性基质,被广泛应用于细胞培养和实验室研究中。

它由一种称为基质金属蛋白酶的酶解产物制备而成,可以模拟细胞所处的基质环境,为细胞提供生长和分化所需的支持。

Matrigel的成胶原理涉及到其特殊的化学和生物特性。

Matrigel的主要成分是一种称为基质金属蛋白酶的酶解产物。

基质金属蛋白酶是一类酶,在胶原蛋白等基质分子的酶解和重塑过程中起重要作用。

当基质金属蛋白酶与胶原蛋白接触时,它们会降解胶原蛋白的三维结构,使其变得可溶解。

通过一系列的化学处理,可以将酶解产物提取出来,形成具有胶状结构的Matrigel。

Matrigel的成胶原理还涉及到其生物特性。

Matrigel含有多种细胞外基质蛋白质,如胶原蛋白、纤维连接蛋白、腺苷酸酰化酶等,这些蛋白质可以为细胞提供支持和指导细胞行为。

Matrigel中的胶原蛋白可以提供细胞所需的机械支撑,并与细胞表面的整合素相互作用,促进细胞黏附和迁移。

纤维连接蛋白则可以通过与细胞的细胞间连接结合,促进细胞间的相互作用和细胞外基质的形成。

腺苷酸酰化酶则参与细胞外信号传导通路,调节细胞的生长和分化。

在实验室中,研究人员经常使用Matrigel来建立细胞培养的三维模型。

这种模型可以更好地模拟细胞所处的生理环境,为研究细胞行为和细胞与基质的相互作用提供了重要的工具。

Matrigel可以用来培养和分化干细胞,研究细胞的分化机制;它也可以用来培养肿瘤细胞,模拟肿瘤的生长和扩散过程。

此外,Matrigel还可以用于药物筛选和治疗方法的研发。

总结起来,Matrigel的成胶原理是由基质金属蛋白酶的酶解产物组成的生物活性基质。

它具有特殊的化学和生物特性,可以模拟细胞所处的基质环境,为细胞提供支持和指导细胞行为。

Matrigel的广泛应用在细胞培养和实验室研究中发挥着重要的作用,为研究细胞行为和基质相互作用提供了重要的工具。

Matrixyl 3000(棕榈酰寡肽+棕榈酰四肽7),详细介绍其抗衰效果

Matrixyl 3000(棕榈酰寡肽+棕榈酰四肽7),详细介绍其抗衰效果

Matrixy1.3000(棕桐酰寡肽+棕桐酰四肽-7),详细介绍其抗衰效果几乎每个人都愿意掏空钱包来购买抗衰老护肤品。

而想要不浪费,最关键的就是,直接购买最有效果的抗哀老护肤品,比如含有Matrixy1.3000的。

Matrixy1.3000(棕桐酰三肽-1+棕桐酰四肽-7)这可能是最有效的抗衰老肽之一,可以向您的身体发出信号,产生更多的胶原蛋白和弹性蛋白,从而减少皱纹、减少下垂、改善水分和水合作用水平以及增强紧致度。

MatriXy1.3000是源于法国的肽组合物,”是第一个基于Matrikine肽技术的抗衰老成分Matrikine是一种肽(最多50个宓基酸的链),由抗皱活性成分组成,有助于皮肤结构更有效地发挥作用。

这就像从加油站的手洗车到自动洗车一样;这个过程要快得多,并且会产生更光滑、更干净、更“新”的外观。

通过将Matrixy1.3000精华液涂抹到您的皮肤上,将在短时间内获得惊人且明显的效果。

这些效果包括改善弹性、改善光泽、抚平皱纹、减少细纹和下垂。

这种“神奇成分”实际上是如何发挥作用的?它通过细胞信号传导调节细胞活动,以便您的皮肤在胶原蛋白分解后立即产生新的胶原蛋白。

当然,胶原蛋白和弹性蛋白会随着年龄的增长而降解,并且由于这些化合物对于保持皮肤紧致和弹性至关重要,因此它们的缺乏会导致细纹和皱纹。

但Matrixv1.3∞0不同于任何其他抗衰老成分。

它与许多其他脓不同,因为它的效果是持久的。

它有两个功能,并J1.专门负道这些功能:刺激胶原蛋白合成和修复损伤。

它能够深入渗透到皮肤层•(与仅治疗上表面的其他肽不同),几乎没有副作用。

总而言之,MatriXyI3000名副其实,是最好的抗衰老成分,让您拥有持久、年轻的肌肤。

甘露聚糖肽联合人参皂苷对浅表性膀胱癌患者细胞免疫功能及血管内皮生长因子的影响

甘露聚糖肽联合人参皂苷对浅表性膀胱癌患者细胞免疫功能及血管内皮生长因子的影响

甘露聚糖肽联合人参皂苷对浅表性膀胱癌患者细胞免疫功能及血管内皮生长因子的影响引言浅表性膀胱癌是一种常见的泌尿系统肿瘤,其易复发和易转移的特点使得它成为一种治疗难度较大的肿瘤。

传统的治疗方法通常包括手术切除、放疗和化疗等,但是这些治疗方式往往伴随着一系列的副作用和并发症,对患者的生活质量和长期生存率造成了一定的影响。

近年来,一些研究表明甘露聚糖肽和人参皂苷对膀胱癌具有一定的抗肿瘤活性,但是它们对膀胱癌患者细胞免疫功能和血管内皮生长因子的影响还不够清楚。

本研究旨在探讨甘露聚糖肽联合人参皂苷对浅表性膀胱癌患者细胞免疫功能及血管内皮生长因子的影响,为膀胱癌的靶向治疗提供新的思路和理论依据。

方法1. 研究对象:选择符合诊断标准的浅表性膀胱癌患者作为研究对象,共100例。

2. 实验分组:将患者随机分为实验组和对照组,每组各50例。

实验组患者接受甘露聚糖肽联合人参皂苷治疗,对照组患者接受传统治疗。

3. 观察指标:观察患者治疗前后的细胞免疫功能指标包括T淋巴细胞亚群、白细胞介素、干扰素等指标的变化,以及血管内皮生长因子的表达水平。

结果经过治疗后,实验组患者的T淋巴细胞亚群和白细胞介素、干扰素等细胞免疫功能指标均有明显改善,而对照组的改善程度较小。

血管内皮生长因子的表达水平也在实验组患者中得到一定的抑制,而对照组的抑制效果不显著。

讨论甘露聚糖肽和人参皂苷联合治疗能够显著改善浅表性膀胱癌患者的细胞免疫功能,减少血管内皮生长因子的表达,从而达到抑制肿瘤生长和复发的作用。

这为膀胱癌的靶向治疗提供了新的思路和方法。

本研究还存在一些不足之处,例如样本量偏小、随访时间不够长等,需要进一步完善。

ⅸ型胶原基因的作用

ⅸ型胶原基因的作用

ⅸ型胶原蛋白是一种重要的结缔组织蛋白,在人体中扮演着重要的角色。

ⅸ型胶原基因则是编码这种蛋白质的基因。

ⅸ型胶原蛋白主要存在于皮肤、血管壁、内脏器官、软骨和眼球等组织中,它对这些组织的结构和功能具有重要影响。

作为结缔组织的一部分,ⅸ型胶原蛋白的作用主要包括:
1. 结构支撑:ⅸ型胶原蛋白参与形成组织的结构支撑,使得组织能够保持形态稳定性,例如在皮肤和血管壁中起到重要作用。

2. 细胞黏附:ⅸ型胶原蛋白可以提供细胞黏附所需的支持,促进细胞间和细胞与基质之间的黏附和相互作用。

3. 肌肉和关节的支持:ⅸ型胶原蛋白在软骨、肌腱和关节中起到支持和维护的作用,有助于维持这些组织的弹性和稳定性。

当ⅸ型胶原基因发生突变或异常时,可能会导致相关蛋白质结构或功能发生改变,进而引发一系列疾病或遗传性疾病。

例如,ⅸ型胶原基因突变可能导致先天性结缔组织疾病,如Ehlers-Danlos 综合征等。

这些疾病可能影响到结缔组织的稳定性、弹性以及相关器官和组织的正常功能。

总之,ⅸ型胶原基因对于编码ⅸ型胶原蛋白,它的正常功能对于人体的结缔组织及相关器官的健康和正常功能都至关重要。

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Cancer and Metastasis Reviews24:425–439,2005.C 2005Springer Science+Business Media,Inc.Manufactured in The Netherlands.Clinging to life:cell to matrix adhesion and cell survivalPeter J.Reddig and Rudy L.JulianoDepartment of Pharmacology,School of Medicine,University of North Carolina,Chapel Hill,NC27599Key words:anoikis,integrin,Bim,Bax,PI3-kinase,FAKSummaryCell to matrix adhesion regulates cellular homeostasis in multiple ways.Integrin attachment to the extracellular matrix mediates this regulation through direct and indirect connections to the actin cytoskeleton,growth factor receptors,and intracellular signal transduction cascades.Disruption of this connection to the extracellular matrix has deleterious effects on cell survival.It leads to a specific type of apoptosis known as anoikis in most non-transformed cell types.Anchorage independent growth is a critical step in the tumorigenic transformation of cells.Thus,breaching the anoikis barrier disrupts the cell’s defenses against transformation.This review examines recent investigations into the molecular mechanisms of anoikis to illustrate current understanding of this important process.1.IntroductionAdhesion of cells to the extracellular matrix stimulatessignal transduction cascades that have been shown toimpinge on cell growth,differentiation,and cell death[1–4].In particular,numerous investigations have de-lineated the important role of cell adhesion in cellsurvival and apoptosis and have been reviewed else-where[5–8].This review will focus on recent inves-tigations into the regulation of cell death and survivalthrough signals regulated by adhesion of cells to theextracellular matrix.1.1.Molecular regulation of apoptosisTo understand the role of adhesion in cell survival,abrief introduction to the mechanisms of apoptosis ascurrently understood is required.Apoptosis removesexcess cells from tissues during normal growth anddevelopment.During apoptosis,proteases preciselydismantle the apoptotic cell through the digestion ofkey structural and signaling proteins.Additionally,thechromosomes themselves are torn asunder by nucle-ase digestion.The cell is eventually broken into smallmembrane enclosed particles that are phagocytosedby neighboring cells or professional phagocytes[9–11].Caspases are the cysteine proteases that cleave atconserved aspartic acids and are critical to apopto-sis.The apoptotic caspases are separated into a hi-erarchy of initiators(caspase-2,-8,-9,and-10)andexecutioners(caspase-3,-6,and-7).These moleculesexist as zymogens in the cell with very low activ-ity.Their activity can be induced by treatment ofthe cell with ligands for death receptors or cellularstress.The initiator caspases exist in the cell as inactivemonomers of large and small subunits.Dimerization ofthese subunits in multi-protein complexes stimulatestheir activation through conformational alterations[12,13].Cellular stress or death receptor initiated cell deathprimarily uses caspase-9and caspase-8,respectively,to start the caspase cascade.Clustering of initiator cas-pases stimulates their activation and the subsequentstimulation of the caspase cascade.Cleavage of theinitiator caspases is no longer postulated to be neces-sary for their activation.The activation of caspase-9isfacilitated by its association with apoptotic proteaseactivating factor1(Apaf-1)bound to cytochrome cin a structure denoted the apoptosome.Dimerizationalso appears to be the important event for the acti-vation of the caspase-8zymogen in the multi-proteindeath inducing signaling complex(DISC)(see below).Executioner caspases exist in the cytosol as inactivedimers.The limited proteolysis of their inter-domain426Reddig and Julianolinkers,usually by initiator caspases,leads to their ac-tivation through conformational changes[9,13–15]. Receptor mediated activation of apoptosis,also known as the extrinsic pathway,leads to the asso-ciation of a death adapter protein with the receptor and the recruitment of a caspase-8monomer to the adapter protein forming the death inducing signaling complex,DISC.In the case of the Fas death receptor, after binding of Fas ligand(Fas-L),the adapter FADD (Fas-associated death domain)binds to Fas through death domains on the two molecules.FADD recruits procaspase-8monomers in a multiprotein complex to allow dimerization and activation of procaspase-8. Caspase-8can also cleave Bid to form tBid stimu-lating the release of cytochrome c from the mito-chondria and amplification of this caspase cascade [9,16].A central event in cell stress induced apoptosis,the intrinsic pathway,is the mitochondrial outer membrane permeablization and the release of mitochondrial pro-teins like cytochrome c.Cytosolic cytochrome c can in-teract with Apaf-1to activate caspase-9.This activates caspase-3and stimulates the caspase cleavage cascade. This cascade is initiated by the pro-apoptotic,BH3-only family of proteins Bad,Bim,Bmf,Bid,Noxa, and Puma.These proteins stimulate the translocation of homo-oligomerized pro-apoptotic proteins of the Bax family(Bax,Bak,and Bok)to the mitochondrial outer membrane.This leads to the mitochondrial outer mem-brane permeablization and release of cytochrome c and other pro-apoptotic factors.This disruption may result from intrinsic pore forming activity of the Bax pro-teins or their interaction with mitochondrial channel proteins such as the voltage dependent anion channel. The Bcl-2family of proteins(Bcl-2,Bcl-x L,Bcl-w, Mcl-1,and A1/Bfl-1)is structurally related to the Bax and BH3-only families and prevents disruption of the mitochondrial outer membrane and apoptosis[10,11, 17–19].The precise interplay between these proteins and their function remains controversial.The original model of Bcl-2of inhibiting Bax function through het-erodimerization is no longer favored because of the difficulty in detecting this complex under physiolog-ical conditions.Bcl-2proteins may block apoptosis by maintaining mitochondrial membrane integrity and preventing pore formation though an undefined mech-anism.Additionally,Bcl-2family proteins can bind BH3-only proteins and may act as rheostat for BH3-only protein levels.Thus,the level of Bcl-2proteins would determine the threshold for BH3-only activation of Bax family proteins[10,11,17–19].Bax family proteins stimulate the release of cy-tochrome c by a conformational change that stimulates homo-oligomerization.This conformational change in Bax proteins may help them to induce pore formation and permeablization of the mitochondrial outer mem-brane,loss of the inner mitochondrial membrane po-tential,and release of cytochrome c.The signal for the activation of Bax family proteins and their interaction with the mitochondrial outer membrane remains ill de-fined.One mechanism for Bax activation may be its interaction with a proteolytically cleaved form of the BH3-only protein Bid,t-Bid[10,11,17–19].1.2.AnoikisAnoikis is a specific type of apoptosis caused by de-tachment of a cell from its supportive matrix and was originally described in MDCK cells by Frisch and Fran-cis[20].Early work suggested that the JNK/SAPK signaling was important for the induction of anoikis. However,later work pointed to a more prominent role for other signaling molecules like PI3-kinase,FAK,and the Ras/MAPK cascade in the regulation of anoikis[7]. Recent work has further delineated the role of these and other signaling molecules and that of the apoptotic reg-ulatory proteins themselves in adhesion regulated cell survival.2.BH3-only,Bax,and Bcl-2proteins and anoikis 2.1.Bim and anoikisBH3-only proteins appear to act as sensors of cellu-lar stress and have no intrinsic ability to induce cell death on their own.Two members of this family Bim and Bmf appear to be important sensors of changes in the actin cytoskeleton.The Bim isoforms Bim EL and Bim L bind to LC8,also known as cytoplasmic dynein light chain(DLC1),a component of the microtubule-associated dynein motor complex.These proteins are sequestered in the dynein complex until an apoptotic stimuli induces their release[21].The BH3only pro-tein Bmf binds to dynein light chain-2localizing it to the myosin V motor.Treatment of cells with cytocha-lasin D or induction of anoikis initiates the release of Bmf from the cytoskeleton[22].Several studies have recently investigated the role Bim plays in anoikis.Clinging to life:cell to matrix adhesion and cell survival427It has been previously demonstrated that activation of the epidermal growth factor receptor(EGFR)and the subsequent stimulation of the Erk/MAPK cascade were capable of suppressing anoikis.For example,the introduction of a Raf estrogen receptor fusion protein (Raf-ER)suppressed anoikis in MCF-10A cells and CCL39lungfibroblasts cells upon activation of Raf [23,24].Furthermore,the survival of MCF-10A cells in suspension depended on the autocrine production of EGFR ligands HB-EGF,TGFα,and amphiregulin[24]. The Erk/MAPK cascade directly leads to the phospho-rylation of Bim EL which can inhibit its function and lead to its degradation[25,26].Several recent studies have examined the connec-tion between the EGFR-Erk/MAPK survival path-way,Bim,and anoikis.One investigation found that during anoikis in immortalized mammary breast ep-ithelial cells(MCF-10A),all three Bim isoforms Bim EL,Bim L,and Bim S were elevated.In adher-ent cells,EGFR repressed Bim expression through the Erk/MAPK pathway.Suppression of Bim ex-pression by hyper-activation of the EGFR/Erk/MAPK signaling pathway by over expression of EGFR or constitutively active MAPK components blocked anoikis.Conversely,the loss ofβ1integrin engage-ment in detached cells repressed expression of the EGFR and increased Bim expression.Thus,the neg-ative regulation of Bim expression by adhesion and EGFR signaling were implicated in the suppression of anoikis in breast epithelial cell lines(Figure1) [27].An additional investigation found that suspension culture of the MCF-10A cells enhanced the expression of the Bim EL,and Bim L[28].Again,activation of the Erk/MAPK cascade suppressed anoikis.Erk activation stimulated phosphorylation and the proteasome depen-dent degradation of Bim EL.These alterations were not observed for Bim L.Furthermore,the elimination of Bim from MCF-10A cells by RNAi partially blocked anoikis.The relevance of the phosphorylation to the suppression of anoikis was indeterminate in this study since a phosphorylation resistant mutant of Bim EL still induced apoptosis(Figure1)[28].The cells used in the previous studies to examine Bim’s role in anoikis were immortalized breast epithe-lial cell lines.Interestingly,examination of the same phenomena in primary breast epithelial cells or a breast epithelial cell line with a more normal phenotype(FSK-7)gave different results.Detachment from substrate in the absence of growth factors induced dephosphoryla-tion of Bim EL and Erk.However,in the presence of a cocktail of growth factors,2%fetal calf serum,5ng/ml EGF,and5µg/ml insulin,Bim EL and Erk phosphory-lation and protein levels were maintained in detached cells and cell death still occurred within4–8hours.In a parallel examination of MCF-10A cells,the status of Bim EL and Erk phosphorylation also did not corre-late with survival in suspension.The MCF-10A cells were able to survive independently of adhesion status and were only dependent on growth factor signals for survival.In spite of no detectable role in anoikis in normal breast epithelial cells,Bim EL was important for EGF dependent survival.Suppression of Bim EL by RNAi in-hibited apoptosis in response to EGF withdrawal with no effect on anoikis.The absence of growth factors induced dephosphorylation of Bim EL and Erk and in-creased the level of Bim EL.Conversely,treatment of adherent cells with epidermal growth factor stimulated Bim EL phosphorylation in a MEK-Erk dependent man-ner and inhibited apoptosis.These results,in contrast to the other investigations, indicate that adhesion is critical for survival of breast epithelial cells,but anoikis can occur independently of Bim and Erk.However,in agreement with the other studies,Bim senses changes in the epidermal growth factor dependent survival signals with the stimulation of the Erk/MAPK cascade being needed for Bim EL and Erk phosphorylation and inhibition of apoptosis (Figure1)[29].2.2.BaxThe proapoptotic protein Bax contributes to the induc-tion of apoptosis by translocating to the outer mito-chondrial membrane,inducing its permeablization,and allowing the release apoptotic factors like cytochrome c[11,17].During anoikis in mammary epithelial cells, Bax translocation to the mitochondria depends on the loss of survival signals from FAK.As in other cell death programs,Bax’s movement to the mitochondria dur-ing anoikis correlates with it undergoing an activating, conformational change.The Bax translocation is inde-pendent of caspase activation and cytochrome c release. Detachment of cells from the extracellular matrix stim-ulates the translocation of Bax to the mitochondria in aboutfifteen minutes.However,the cells do not die immediately,rather death occurs after several hours in suspension.If cells are re-plated quickly enough,Bax428Reddig and JulianoFigure1.Suppression of apoptosis and anoikis in breast epithelial cells.(A).Attachment to the extracellular matrix and stimulation of growth factor signaling cascades suppresses the activity of apoptotic factors.EGF binding to the EGFR stimulates Erk/MAPK signaling,which negatively regulates Bim by phosphorylation and stimulating its degradation.This prevents Bim from antagonizing Bcl-2function or stimulating Bax activation.Inhibition of Bim suppresses disruption of the mitochondria and the induction of cell death.The adhesion survival signals suppress anoikis in a Bim dependent and independent manner depending on the time in suspension and the cell type used(B).Detachment from the matrix or growth factor deprivation shuts down these signaling cascades.Some investigations have found that suspension culture actively down regulates EGFR adding to the suppression of survival signals.Once survival signals are suppressed the levels of Bim increase in its dephosphorylated form.This leads to activation of Bax,inhibition of Bcl-2,and cell death.Clinging to life:cell to matrix adhesion and cell survival429will exit the mitochondria and the cells will remain viable[30,31]The temporal discrepancy between Bax mitochon-drial translocation and execution of cell death during anoikis was examined to determine how this related to spatial and conformational changes in Bax.In viable, anchored cells,Bax exists in the cytoplasm as an in-active monomer.During anoikis,Bax translocates to the mitochondria in the inactive ing a con-formation sensitive antibody,the activating conforma-tional change in Bax was observed only for Bax in the mitochondrial membrane.As observed for other apoptotic events,the mitochondrial Bax oligomerized with other Bax monomers.The activated Bax formed clusters just prior to loss of mitochondrial membrane potential and the release of cytochrome c.These events were independent of caspase activation.Interestingly, suspended cells commit to the apoptotic pathway be-fore Bax clustering,loss of membrane potential,or the release of cyotchrome c,but after the localization of Bax to the mitochondria.Thus,an undefined event oc-curs that commits cells to apoptosis that appears to be independent of Bax clustering,loss of mitochon-drial membrane potential,and release of cytochrome c [32].2.3.BidAs described above,Bid is a BH3only protein that is cleaved to form truncated t-Bid during death receptor mediated apoptosis.Death receptors signals for cleav-age of caspase8and t-Bid have been implicated in the regulation of anoikis[33–35].In contrast,studies of anoikis in mammary epithelial cells found that activa-tion of caspase-8and cleavage of Bid were not nec-essary for anoikis[30].Interestingly,during anoikis in mammary epithelial cells,Bid was found to translocate to the mitochondria as a full-length protein.Cleavage of Bid was not necessary for anoikis.The movement to the mitochondria by Bid was independent of caspase-8activation and translocation of Bax or Bcl-2family proteins to the mitochondria.Suppression of FAK and PI3-kinase signals with dominant negative mutants also stimulated the translocation of Bid to the mitochon-dria.Thus,full length Bid appears to be important for anoikis and suppression of the FAK/PI3-kinase survival signals by cell detachment stimulates its apoptotic ac-tivity[36].2.4.Bit1Adhesion to the extracellular matrix through certain integrins likeα5β1can stimulate Bcl-2expression [37,38].To identify new modulators of anoikis,Jan et ed a cDNA library screen to identify genes which could rescue integrin stimulated Bcl-2expres-sion in cells harboring an integrinα5subunit lacking its cytoplasmic domain[39].Surprisingly,a pro-apoptotic protein that inhibited Bcl-2transcription was isolated and named Bit1,Bcl-2inhibitor of transcription.Bit1 is a unique mitochondrial protein with no identifiable homologues and potently induces apoptosis when ex-pressed in the cytoplasm.This activity is specifically repressed by adhesion tofibronectin throughα5β1.The original cDNA clone may have been mutated in such a way that allowed it to act like a dominant negative and allowing it to rescue Bcl-2expression.During anoikis,Bit1translocates from the mitochon-dria to the cytoplasm and interacts with AES,a mem-ber and negative regulator of the Groucho/TLE family of transcriptional regulators.The interaction of Bit1 and AES initiates cell death independently of caspase activation,Bcl-2or Bcl-x L levels,or PI3-kinase ac-tivity.This suggests that Bit1acts downstream or in parallel to these pathways,likely at the level of Bcl-2 expression.Supporting this idea,the transcriptional regulator TLE1,which binds AES,blocks Bit1in-duced apoptosis when over-expressed.The induction of apoptosis positively correlates with TLE1’s abil-ity to stimulate Bcl2expression and Bit1to inhibit it.Bit1may be key mediator of the adhesion sur-vival signal with adhesion being the only upstream survival signal found to repress its death inducing activity when ectopically placed in the cytoplasm [39].3.PI3-kinaseThe generation of3 phosphorylated phosphoinositides (PI3,4P&PI3,4,5P)is mediated by the enzyme PI3-kinase.These phosphorylated phosphoinositides stimulate the recruitment of PKB/Akt to the mem-brane through its PH domain where PDK-1/PRK-2 phosphorylation of PKB/Akt at Thr-308and Ser-473 activates PKB/Akt.Activated PKB/Akt mediates cell survival through phosphorylation of several substrates including Bad and pro-caspase-9and inhibiting their function.PI3-kinase and the subsequent activation of430Reddig andJulianoFigure 2.Suppression of anoikis through PI3-kinase signaling.Upon stimulation with growth factors and adhesion PI3-kinase stimulates the generation of the phosphoinositide PIP 3.PIP 3binds to PKB/Akt helping to recruit it to the membrane where PDK-1can phosphorylate PKB/Akt on threonine 308.The activated TrkB receptor stimulates this pathway for suppression of anoikis.Adhesion can stimulate PKB/Akt phosphorylation on serine-473through ILK-1activation.PP2A associated with β1integrins negatively regulates PI3-kinase signaling by dephosphorylation of serine 473and turning off this survival pathway.Cdc42stimulates the PI3-kinase/PKB/Akt pathway through Rac.Rac and PI3-kinase may function in a positive feedback loop that stimulates this survival pathway.For cell survival,active PKB/Akt suppresses the function of pro-apoptotic proteins and stimulates survival proteins.PKB/Akt directly phosphorylates Bad,pro-caspase 9,and DAP-3to stimulate survival by inhibiting their function.PKB/Akt also stimulates the adhesion mediated increase in survivin levels.PKB/Akt play a central role in regulation of adhesion,mediated survival signals [7,40].Recent investigations have further delineated these connections.In a study to identify amino acids in the integrin β1cytoplasmic domain that specifically regulate sur-vival signaling,tryptophan 775on the β1cytoplasmic domain was found to be important for stimulation of PKB/Akt activity [41].Substitution of this tryptophan on the β1cytoplasmic domain with an alanine specifi-cally inhibits PKB/Akt activity and decreases cell sur-vival in cells expressing this mutant.Mutation of this tryptophan does not significantly interfere with inte-grin activation,binding to αsubunits,talin,vinculin,or α-actinin,localization to focal adhesion,or activa-tion of PI3-kinase.Instead,β1was found to selectively recruit a subpopulation of protein phosphatase 2A (PP2A)to β1cytoplasmic domain complexes.PP2A selectivelydephosphorylated PKB/Akt and reduced integrin me-diated survival signaling.The inhibitory nature of this mutant β1arises from an increase in the activity of bound PP2A,not the amount,and a subsequent de-crease in PKB/Akt phosphorylation on serine 473.The presence of PP2A associated with β1may allow for rapid suppression of PKB/Akt activity in response to changes in adhesion status (Figure 2)[41].In cells derived from stratified squamous epithelia,the selective activation of PI3-kinase via differential ex-pression of integrin subunits selectively regulates cell survival.In normal stratified squamous epithelia the αv integrin subunit normally pairs with the β5subunit as a receptor for vitronectin.During hyper-proliferation or in transformed cells the αv pairing with β5is re-placed with αv paired with β6.The switch to αv β6confers protection from anoikis in squamous epithe-lial cells.The increased adhesion independent survivalClinging to life:cell to matrix adhesion and cell survival431potentiated byαvβ6results from its ability to stimulatePI3-kinase in suspension whileαvβ5cannot.Replac-ing the cytoplasmic domains ofβ6with that ofβ5suppressed its survival phenotype and ability to acti-vate PI3-kinase;thus,localizing these functions to the β6cytoplasmic domain.Therefore,selective integrin isoform activation of PI3-kinase confers differentialsurvival phenotypes and this could be important forcellular transformation[42].Another connection in the web of PI3-kinase inter-actions regulating anoikis was found to be the GTP-binding,death associated protein-3(DAP-3).DAP-3is a pro-apopptotic protein with mitochondrial andcytoplasmic pools that regulates cell death mediatedby death receptor ligands like TNF-α.Suppression ofDAP3expression in HEK293cells inhibited anoikis.Cell detachment stimulated association of DAP3withFADD and increased caspase-8activity.Expression ofan active Akt inhibited the DAP-3/FADD association,caspase-8activation,and anoikis in suspended cells.The direct phosphorylation of DAP3by Akt mediatedAkt’s ability to stimulate survival in suspended cells.Additionally,adhesion of suspended cells to vitronectinincreased survival,Akt activation,and phosphorylationof DAP3.Thus,DAP3appears to be an important Akttarget in adhesion mediated survival signaling[43].Another target of the PI3-kinase pathway importantfor survival may be the IAP family protein survivin.Itis not expressed in most adult tissues,but is elevated innumerous human cancers and is associated with a poorprognosis[19].The regulation of survivin by adhesionwas examined in prostate cancer cell lines.Adhesion ofa malignant cancer cell line tofibronectin increased theexpression of survivin and resistance to TNF-αinducedapoptosis.A dominant negative survivin blocked theprotective effect of adhesion tofibronectin.Conversely,a wild type survivin imparted resistance to apoptosis tocells cultured in suspension.This elevation of survivinlevels only occurred in the tumorigenic cell types exam-ined.The survivin andfibronectin dependent increasein survival was dependent on theβ1A integrin isoformand PI3-kinase signaling(Figure2)[44].The importance of the PI3-kinase/AKT survival-signaling cascade in anoikis was reinforced in a screenfor suppressors of anoikis in rat intestinal epithelialcells(RIE).TrkB,a neurotrophic tyrosine kinase re-ceptor,was found to potently suppress anoikis in RIEcells in the presence or absence of its ligand,brain-derived neurotrophic factor.Elevation of TrkB levelsin RIE cells disrupted epithelial organization,stim-ulated cell aggregation,and enhanced the prolifera-tion of spheroids in suspension.The TrkB survival signal appeared to be specific for anoikis because it could not suppress apoptosis in serum deprivedfibrob-lasts overexpressing c-Myc.TrkB activated the PI3-kinase cascade and this activation was necessary for its suppression of anoikis and was independent of the cell aggregation.Rac,p70S6-kinase,and MEK,(down-stream effectors of PI3-kinase)were not necessary for its survival function.The importance of TrkB’s sup-pression of anoikis was confirmed by its ability to form metastatic tumors alone or in combination with its lig-and.TrkB and its ligand are overexpressed in several human tumors types.Thesefindings support the im-portance of anoikis,TrkB,and PI3-kinase signaling in tumorigenic transformation of cells(Figure2)[45]. The individual Akt isoforms may have unique and non-overlapping roles in anchorage dependent cell sur-vival.In intestinal epithelial cells Akt-1activation by cell adhesion throughβ1integrin,FAK,and PI3-kinase is critical for cell survival in all states of enterocyte differentiation.However,Akt-2is not regulated by PI3-kinase and cannot replace PKB/Akt in survival signaling[46].Although important in adhesion dependent survival signaling,the PI3-kinase/Akt survival pathway can be circumvented.In an examination of anoikis in a panel of breast cancer cell lines,Akt activation did not strongly correlate with cell survival.Even pharmacological in-hibition of PI3-kinase did not impart anoikis sensitivity to cells with high PKB/Akt phosphorylation levels[47]. Clearly,PI3-K has a central role in anoikis.The iden-tification of novel modes of regulation of its activity and substrates in relation to anoikis adds to our knowledge of this pathway.Further investigation into the precise interplay of these events and their deregulation in dis-ease will be required for a complete understanding of PI3-kinase regulation of anchorage dependent survival.4.ILKThe integrin linked kinase(ILK)binds to theβ1cy-toplasmic domain and is regulated by growth factor receptors and integrins in cooperation with PI3-kinase. ILK activity is important for cell survival.Substantial evidence indicates that ILK can enhance phosphory-lation of PKB/Akt on Ser-473that,in combination with Thr-308phosphorylation by PDK-1,is essen-tial for PKB/Akt activation[40,48].However,recent432Reddig and Julianoinvestigations suggest that ILK may not be the media-tor of the Ser-473phosphorylation of PKB/Akt[49]. To definitively show that ILK is the mediator of PKB/Akt phosphorylation,ILK was knocked out in cultured cells using both RNAi inhibition of ILK ex-pression and Cre/Lox conditional gene disruption.The elimination of ILK expression blocked Ser-473phos-phorylation of PKB/Akt.The loss of ILK in cells also elevated the levels of apoptosis.Thus,ILK has an im-portant role in the Ser-473phosphorylation of PKB/Akt and cell survival.However,whether ILK directly medi-ates this phosphorylation or regulates the activity of an intermediary kinase is yet to be determined(Figure2) [50].ILK interacts with the calponin homology domain-containing integrin-linked kinase-binding protein(CH-ILKBP)in a ternary complex with PINCH.CH-ILKBP has also been identified as actopaxin orα-parvin.This trimeric complex of proteins localizes to focal adhe-sions[51–53].Investigations of CH-ILKBP in ILK sig-naling found it to be important for cell survival. Suppression of CH-ILKBP with RNAi increased the level of apoptosis without disruption of focal adhe-sions or ILK focal adhesion localization.This increased apoptotic activity positively correlated with a loss of phosphorylation of Thr-308and Ser-473of PKB/Akt and inhibition of its activation.The impairment of PKB/Akt activation resulted from impaired membrane localization in the absence of CH-ILKBP.Artificially targeting PKB/Akt to the membrane permitted its ac-tivation in the absence of CH-ILKBP.The Erk/MAPK and p38/MAPK pathways did not significantly con-tribute to survival signaling mediated by CH-ILKBP and PKB/Akt.Thus,membrane targeting of PKB/Akt by CH-ILKBP plays an important role in cell survival (Figure2)[54].The other member of this dynamic trio,PINCH, also appears to play an important role in cell survival. The depletion of PINCH-1with RNAi led to inhibi-tion of cell spreading and induction of apoptosis.This increased apoptosis positively correlated with the in-hibition of PKB/Akt phosphorylation of Thr-308and Ser-473.Again,depletion of ILK suppressed Ser-473 phosphorylation.However,an active PKB/Akt could not block the apoptosis induced by RNAi suppression of PINCH-1or ILK-1.Thus,PINCH-1and ILK-1may have functions downstream or in parallel to PKB/Akt activation that are important for cell survival.The loss of PINCH-1stimulated the proteasomal degradation of ILK-1and CH-ILKBP.Expression of the PINCH-1homologue,PINCH-2,restored the lev-els of ILK-1and CH-ILKBP.However,the reduction in PKB/Akt activation and cell viability was not rescued by the presence of PINCH-2.Thus,the degradation of ILK-1and CH-ILKBP was not necessary for the re-duced viability in the absence of PINCH-1.However, caspase inhibition blocked the apoptotic response me-diated by PINCH-1reduction.Thus PINCH-1may be a conduit for survival signals from PKB/Akt or other parallel pathways[55].Activation of PKB/Akt depends on ILK and its as-sociated proteins.Membrane association of PKB/Akt mediated by CH-ILKBP appears to be a prereq-uisite for PKB/Akt activation.Once at the mem-brane PKB/Akt depends on the presence of ILK-1and PINCH-1,in addition to other proteins,for activation via phosphorylation.However,activation of PKB/Akt is not the only critical function of PINCH-1and ILK-1given that artificially activated PKB/Akt did not sustain cell viability in their absence. Thus,this complex of integrin-associated proteins has a pivotal role in the maintenance of cell viability (Figure2).5.Focal adhesion kinase(FAK)FAK plays a central role in transmitting adhesion de-pendent signals and is important for adhesion de-pendent survival signaling.FAK interacts with sev-eral effector proteins,like the p85catalytic subunit of PI3-kinase,Src,Shc,and Cas,in adherent cells to signal.Importantly,anoikis can be prevented by ex-pression of constitutively active FAK mutants.The disruption of FAK signaling in cancer cells by vari-ous techniques induces cell death after the induction of cell rounding and detachment from the substra-tum.FAK survival signaling depends on the PI3-kinase signaling cascade.Cell death in the absence of FAK survival signals depends on the presence of p53 [7,56].Recent investigations have further delineated the in-timate relationship between FAK and survival signal-ing.FAK was found to directly interact with RIP,a death domain containing serine/threonine kinase[57]. RIP contains a death domain that mediates the inter-action with other death domain proteins in the death receptor complex and regulates death/survival signal-ing through regulation of NF-κB[58,59].Induction of apoptosis in breast cancer cells with the protein。

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