人表皮细胞整合素β1启动子活性分析的研究
摘要
研究背景
表皮干细胞(keratinocyte stem cell, KSC)在皮肤生理功能中的作用得到广泛关注。表皮干细胞具有强大增殖能力,可向各个阶段表皮细胞分化以维持皮肤的正常功能。研究KSC调控增殖分化的分子机制,对于研究创面愈合的机制及KSC在组织工程中的应用有重要的意义。
KSC高表达整合素β1,是KSC的标志物之一,在KSC增殖和分化中扮演重要角色。整合素β1在表皮基底层及毛囊隆突富含KSC的部位高表达,整合素β1的表达水平在KSC表面比已经分化的快速增殖细胞(transit amplifying cell, TAC)高数倍。KSC通常与基底膜粘附,脱离粘附后,开始走向终末分化[1,2]。整合素β1是被认为是维持KSC未分化状态及其增殖能力的粘附分子之一。Jones等发现表皮细胞表达整合素β1水平的高低,与其增殖能力有关[3];整合素β1小RNA干扰研究证明,下调表达整合素β1蛋白,KSC克隆形成率降低,并促进KSC的分化[4]。这些都提示整合素β1在KSC的增殖/分化调控中发挥重要作用。
Piero C等人用MG-63细胞株(人骨肉瘤细胞株)研究证实:整合素β1表达是由近端和远端两个启动子区调控。它们缺少CAAT盒和TATA盒,高GC含量,可作为转录起始的两个独立启动子存在,促进整合素β1基因表达,产生两种mRNA—有相同的编码序列。近端和远端启动子在正常或刺激因素作用下都能促进转录,但具体参与转录水平调控的转录因子及其机制尚不清楚[5]。
人表皮细胞株(Human adult skin keratinocytos ,HaCaT)来源于正常成人皮肤,是具有完整表皮分化能力的永生化细胞株。研究表明,移植到裸鼠上,HaCaT可以分化形成上皮组织,表达特异性分化蛋白标志[6];另外,整合素β1小干扰RNA载体转染HaCaT,能够抑制整合素β1蛋白表达,生长曲线右移,HaCaT的增殖受到抑制[7],由此说明HaCaT可以为研究人表皮细胞分化的调控提供一个非常理想的模型。
我们已经构建了整合素β1启动子的全长启动序列(-1745bp～+11bp)载体pGL3-1755、近端启动子序列(-250bp～+11)载体pGL3-261、远端启动子序列(-1745bp～-304bp)载体pGL3-1442、远端启动子缺失片段载体(-905bp～-304bp)pGL3-602及(-655bp～-304bp)pGL3-352载体,在HaCat细胞中pGL3-602载体活性明显高于其它启动序列片段载体活性,而pGL3-352载体显著低于pGL3-602,分析在远端启动子-905bp～-655bp序列中有整合素β1的高活性启动序列。
研究目的
应用整合素β1启动子荧光素酶报告基因系统,以HaCaT细胞为模型,探讨表皮细胞中整合素β1启动子的转录启动活性区域,为进一步研究表皮干细胞增殖与分化的信号转导机制奠定基础。
研究方法
1.以本实验室前期构建的含整合素β1启动子序列的重组pGL3-602(-905bp～-304bp)载体为模板,用PCR分别扩增并克隆整合素β1启动子区-905bp～-304bp和-655bp～-304bp之间的连续缺失片段载体序列,分别构建荧光素酶报告基因载体pGL3-372(-675bp～-304bp)、pGL3-392(-695bp～-304bp)和pGL3-412(-715bp～-304bp), pGL3-432(-735bp～-304bp)、pGL3-452(-755bp～-304bp)、pGL3-492(-795bp～-304bp)和pGL3-542(-845bp～-304bp)载体,经双酶切、PCR反应及测序鉴定正确后转染HaCaT细胞,检测它们在HaCaT中的启动活性,分析各重组载体在HaCaT中的活性,初步确定整合素β1启动子中的高活性启动序列范围。
2.根据第一部分研究结果,用Tfsitescan软件对该启动子的转录因子结合位点进行分析预测,分析远端启动子可能的高活性转录起始位点及可能参与转录调控的转录因子。
研究结果
1.成功构建了整合素β1启动子区-905bp～-304bp和-655bp～-304bp之间的连续缺失片段载体序列载体pGL3-372(-675bp～-304bp)、pGL3-392(-695bp～-304bp)和pGL3-412(-715bp～-304bp),pGL3-432(-735bp～-304bp)、pGL3-452(-755bp～-304bp)、pGL3-492(-795bp～-304bp)和pGL3-542(-845bp～-304bp)载体,经酶切鉴定及序列测定表明,其序列与GenBank DNA序列数据库对比分析序列一致,且插入方向正确;用此多种质粒转染HaCaT细胞都有启动子活性。
2.整合素β1远端启动子连续缺失片段荧光素酶报告基因载体转染HaCaT细胞并检测荧光素酶活性,并进行统计分析表明,远端启动子系列重组质粒pGL3-352(-655bp～-304bp)、pGL3-372(-675bp～-304bp)、pGL3-392(-695bp～-304bp)、pGL3-412(-715bp～-304bp),pGL3-432(-735bp～-304bp)、pGL3-452(-755bp～-304bp)、pGL3-492(-795bp～-304bp)和pGL3-542(-845bp～-304bp)转染HaCaT细胞后,都有明显启动活性,pGL3-352(-655bp～-304bp)、pGL3-372(-675bp～-304bp)、pGL3-392(-695bp～-304bp)明显低于pGL3-412(-715bp～-304bp),pGL3-432(-735bp～-304bp)、pGL3-452(-755bp～-304bp)、pGL3-492(-795bp～-304bp)和pGL3-542(-845bp～-304bp)载体启动活性。
研究结论
通过构建远端启动子系列缺失片段荧光素酶报告基因载体并转染HaCaT细胞,检测荧光素酶活性(F/R),结果显示:
1、pGL3-352(-655bp～-304bp)、pGL3-372(-675bp～-304bp)和pGL3-392(-695bp～-304bp)载体荧光素酶活性相接近;
2、pGL3-412(-715bp～-304bp)、pGL3-432(-735bp～-304bp)、pGL3-452(-755bp～-304bp)、pGL3-492(-795bp～-304bp)和pGL3-542(-845bp～-304bp)载体荧光素酶活性相接近;
3、pGL3-352(-655bp～-304bp)、pGL3-372(-675bp～-304bp)和pGL3-392(-695bp～-304bp)载体荧光素酶活性显著低于pGL3-412(-715bp～-304bp)、pGL3-432(-735bp～-304bp)、pGL3-452(-755bp～-304bp)、pGL3-492(-795bp～-304bp)和pGL3-542(-845bp～-304bp)载体;
4、综上所述,在整合素β1启动子序列中,位于-686bp～-715bp之间的约30bp中可能有在HaCat细胞中让整合素β1高表达的转录因子结合起始位点。
Background:
At present, the keratinocyte stem cells(KSCs) obtains the widespread attention in theskin physiology function. Keratinocyte stem cells(KSCs) possess the powerfulproliferative capacity, and they also have the ability to differentiate into epidermal cells inevery stage. Investigation of regulative mechanism of KSC proliferation anddifferentiation is vital for wound healing and tissue engineering.
Integrinβ1 is one of the generally accepted molecular markers for theundifferentiation of KSCs.Previous studies have indicated that integrinβ1 playedimportant roles in generation and differentiation of KSCs. High expression of Integrinβ1was found in basal body and folliculus pili of epidermal cell(EC), and in this part stemcell is rich. On surface of KSC integrinβ1 expression is several times more than that intransit amplifying cell(TAC). KSC maintain its characteristics of stem cell throughadhering to basal membrane(BM). If KSC cast off , it will turn to terminaldifferentiation[1,2]. Jones found that epidermal cells with high expression of integrinβ1have the capacity to form more clones[3]. In our previous study, we found that expressionof integrinβ1 was down-regulated after the transfection of siIntegrinβ1 recombinant vectorinto KSCs[4]. The clone formation rate of cells after transfection was lower than thatwithout transfection, which showed that integrinβ1 paticipated in the regulation of KSCproliferation and differentiation.
Piero C et al[6] have shown that the regulatory region of theβ1-integrin genecontains two promoters, one distal and one proximal tandemly situated. The twotandemly promoter regions are very G + C-rich, and lack both a TATA box and a CAATbox .Each promoter drives the expression of a uniqueβ1 gene, and two mRNAs aresynthesized that share the same coding sequence but diverge in the complete 5′untranslated region. but the regulation mechanism in transcription level was still unclear.
HaCaT(Human adult skin keratinocytos ,HaCaT) cell line originates from normalhuman epidermal cells, which have the capacity to proliferate infinitely. Research hasshowed that after injection of HaCaT into subcutaneous skin of the nude mice, it coμlddifferentiate into epithelial tissues, with expression of special markers for differentiation[7].In addition,our previous study indicated that expression of integrinβ1 protein wassupressed by the transfection of siIntegrinβ1 vector. The growth curve of HaCaT cellsafter transfection was moved right forward, indicating that the proliferation of HaCaTcells was inhibited by the transfection[8]. As described above, HaCaT cell line can providean ideal model for the research of regulation of human epidermal cell proliferation.
Objective:
To explore the mechanism of regulation of integrinβ1 expression. HaCaT cells andluciferase reporter gene system containing integrinβ1 promoter were enrolled in our studyto investigate the influence of integrinβ1 on the proliferation and differentiation of humanepidermal cells.
Methods:
Dual-luciferase reporter vectors containing distal part and proximal part of integrinβ1 promoter were constructed successfully. Then they were transfected into HaCaT cellsto investigate their activity after transfection. This can help us to understand the role ofintegrinβ1 in the transcriptive regulation of HaCaT cells.
The main effect of promotor in transcriptional control was determined in accordingto the result in the first part. Tfsitescan software was used to analyze potential bindingsite of transcription factor in the promotor. Dissection and construction of mutationluciferase report gene vector with series deletion of promotor were carry out according toanalytic result. After sequencing, they were transfected into HaCaT cells, then the activityof luciferase was detected, and the activity of distal promoter of integrinβ1and potentialtranscriptional control factors participating possibly transcriptional control were analyzed.
Results:
We successfully amplified the whole length of integrinβ1 promoter from humangenome by PCR, and transfected the vector containing proximal ,distal and full part ofintegrinβ1 promoter into HaCaT cells. Analysis of luciferase activity revealed that thedistal part of promoter played an important role in the regulation of integrinβ1 transcripton.
In addition, we successfully constructed series deletion mutation luciferase reportgene vector of promotor:
pGL3-372,pGL3-392,pGL3-412,pGL3-432,pGL3-452,pGL3-492,p GL3-542, andtransfected the series vector into HaCaT cells. Analysis of luciferase activity revealed thatluciferase activity of pGL3-412,pGL3-432,pGL3-452,pGL3-492,p GL3-542 is higher thanpGL3-352 ,pGL3-372,pGL3-392.
Conclusion:
1. The luciferase activity of pGL3-352 ,pGL3-372,pGL3-392 is similar in HaCat.
2. The luciferase activity of pGL3-412,pGL3-432,pGL3-452,pGL3-492,p GL3-542 issimilar in HaCat .
3. The luciferase activity of pGL3-412,pGL3-432,pGL3-452,pGL3-492,p GL3-542 ishigher than pGL3-352 ,pGL3-372,pGL3-392 in HaCat.
4. In the integrinβ1 promoter sequences, the transcription factor binding initiationsite possibly is in 30bp located at between -686bp~-715bp in HaCat cells.
表皮干细胞(keratinocyte stem cell, KSC)在皮肤生理功能中的作用得到广泛关注。表皮干细胞具有强大增殖能力,可向各个阶段表皮细胞分化以维持皮肤的正常功能。研究KSC调控增殖分化的分子机制,对于研究创面愈合的机制及KSC在组织工程中的应用有重要的意义。
KSC高表达整合素β1,是KSC的标志物之一,在KSC增殖和分化中扮演重要角色。整合素β1在表皮基底层及毛囊隆突富含KSC的部位高表达,整合素β1的表达水平在KSC表面比已经分化的快速增殖细胞(transit amplifying cell, TAC)高数倍。KSC通常与基底膜粘附,脱离粘附后,开始走向终末分化[1,2]。整合素β1是被认为是维持KSC未分化状态及其增殖能力的粘附分子之一。Jones等发现表皮细胞表达整合素β1水平的高低,与其增殖能力有关[3];整合素β1小RNA干扰研究证明,下调表达整合素β1蛋白,KSC克隆形成率降低,并促进KSC的分化[4]。这些都提示整合素β1在KSC的增殖/分化调控中发挥重要作用。
Piero C等人用MG-63细胞株(人骨肉瘤细胞株)研究证实:整合素β1表达是由近端和远端两个启动子区调控。它们缺少CAAT盒和TATA盒,高GC含量,可作为转录起始的两个独立启动子存在,促进整合素β1基因表达,产生两种mRNA—有相同的编码序列。近端和远端启动子在正常或刺激因素作用下都能促进转录,但具体参与转录水平调控的转录因子及其机制尚不清楚[5]。
人表皮细胞株(Human adult skin keratinocytos ,HaCaT)来源于正常成人皮肤,是具有完整表皮分化能力的永生化细胞株。研究表明,移植到裸鼠上,HaCaT可以分化形成上皮组织,表达特异性分化蛋白标志[6];另外,整合素β1小干扰RNA载体转染HaCaT,能够抑制整合素β1蛋白表达,生长曲线右移,HaCaT的增殖受到抑制[7],由此说明HaCaT可以为研究人表皮细胞分化的调控提供一个非常理想的模型。
我们已经构建了整合素β1启动子的全长启动序列(-1745bp～+11bp)载体pGL3-1755、近端启动子序列(-250bp～+11)载体pGL3-261、远端启动子序列(-1745bp～-304bp)载体pGL3-1442、远端启动子缺失片段载体(-905bp～-304bp)pGL3-602及(-655bp～-304bp)pGL3-352载体,在HaCat细胞中pGL3-602载体活性明显高于其它启动序列片段载体活性,而pGL3-352载体显著低于pGL3-602,分析在远端启动子-905bp～-655bp序列中有整合素β1的高活性启动序列。
研究目的
应用整合素β1启动子荧光素酶报告基因系统,以HaCaT细胞为模型,探讨表皮细胞中整合素β1启动子的转录启动活性区域,为进一步研究表皮干细胞增殖与分化的信号转导机制奠定基础。
研究方法
1.以本实验室前期构建的含整合素β1启动子序列的重组pGL3-602(-905bp～-304bp)载体为模板,用PCR分别扩增并克隆整合素β1启动子区-905bp～-304bp和-655bp～-304bp之间的连续缺失片段载体序列,分别构建荧光素酶报告基因载体pGL3-372(-675bp～-304bp)、pGL3-392(-695bp～-304bp)和pGL3-412(-715bp～-304bp), pGL3-432(-735bp～-304bp)、pGL3-452(-755bp～-304bp)、pGL3-492(-795bp～-304bp)和pGL3-542(-845bp～-304bp)载体,经双酶切、PCR反应及测序鉴定正确后转染HaCaT细胞,检测它们在HaCaT中的启动活性,分析各重组载体在HaCaT中的活性,初步确定整合素β1启动子中的高活性启动序列范围。
2.根据第一部分研究结果,用Tfsitescan软件对该启动子的转录因子结合位点进行分析预测,分析远端启动子可能的高活性转录起始位点及可能参与转录调控的转录因子。
研究结果
1.成功构建了整合素β1启动子区-905bp～-304bp和-655bp～-304bp之间的连续缺失片段载体序列载体pGL3-372(-675bp～-304bp)、pGL3-392(-695bp～-304bp)和pGL3-412(-715bp～-304bp),pGL3-432(-735bp～-304bp)、pGL3-452(-755bp～-304bp)、pGL3-492(-795bp～-304bp)和pGL3-542(-845bp～-304bp)载体,经酶切鉴定及序列测定表明,其序列与GenBank DNA序列数据库对比分析序列一致,且插入方向正确;用此多种质粒转染HaCaT细胞都有启动子活性。
2.整合素β1远端启动子连续缺失片段荧光素酶报告基因载体转染HaCaT细胞并检测荧光素酶活性,并进行统计分析表明,远端启动子系列重组质粒pGL3-352(-655bp～-304bp)、pGL3-372(-675bp～-304bp)、pGL3-392(-695bp～-304bp)、pGL3-412(-715bp～-304bp),pGL3-432(-735bp～-304bp)、pGL3-452(-755bp～-304bp)、pGL3-492(-795bp～-304bp)和pGL3-542(-845bp～-304bp)转染HaCaT细胞后,都有明显启动活性,pGL3-352(-655bp～-304bp)、pGL3-372(-675bp～-304bp)、pGL3-392(-695bp～-304bp)明显低于pGL3-412(-715bp～-304bp),pGL3-432(-735bp～-304bp)、pGL3-452(-755bp～-304bp)、pGL3-492(-795bp～-304bp)和pGL3-542(-845bp～-304bp)载体启动活性。
研究结论
通过构建远端启动子系列缺失片段荧光素酶报告基因载体并转染HaCaT细胞,检测荧光素酶活性(F/R),结果显示:
1、pGL3-352(-655bp～-304bp)、pGL3-372(-675bp～-304bp)和pGL3-392(-695bp～-304bp)载体荧光素酶活性相接近;
2、pGL3-412(-715bp～-304bp)、pGL3-432(-735bp～-304bp)、pGL3-452(-755bp～-304bp)、pGL3-492(-795bp～-304bp)和pGL3-542(-845bp～-304bp)载体荧光素酶活性相接近;
3、pGL3-352(-655bp～-304bp)、pGL3-372(-675bp～-304bp)和pGL3-392(-695bp～-304bp)载体荧光素酶活性显著低于pGL3-412(-715bp～-304bp)、pGL3-432(-735bp～-304bp)、pGL3-452(-755bp～-304bp)、pGL3-492(-795bp～-304bp)和pGL3-542(-845bp～-304bp)载体;
4、综上所述,在整合素β1启动子序列中,位于-686bp～-715bp之间的约30bp中可能有在HaCat细胞中让整合素β1高表达的转录因子结合起始位点。
Background:
At present, the keratinocyte stem cells(KSCs) obtains the widespread attention in theskin physiology function. Keratinocyte stem cells(KSCs) possess the powerfulproliferative capacity, and they also have the ability to differentiate into epidermal cells inevery stage. Investigation of regulative mechanism of KSC proliferation anddifferentiation is vital for wound healing and tissue engineering.
Integrinβ1 is one of the generally accepted molecular markers for theundifferentiation of KSCs.Previous studies have indicated that integrinβ1 playedimportant roles in generation and differentiation of KSCs. High expression of Integrinβ1was found in basal body and folliculus pili of epidermal cell(EC), and in this part stemcell is rich. On surface of KSC integrinβ1 expression is several times more than that intransit amplifying cell(TAC). KSC maintain its characteristics of stem cell throughadhering to basal membrane(BM). If KSC cast off , it will turn to terminaldifferentiation[1,2]. Jones found that epidermal cells with high expression of integrinβ1have the capacity to form more clones[3]. In our previous study, we found that expressionof integrinβ1 was down-regulated after the transfection of siIntegrinβ1 recombinant vectorinto KSCs[4]. The clone formation rate of cells after transfection was lower than thatwithout transfection, which showed that integrinβ1 paticipated in the regulation of KSCproliferation and differentiation.
Piero C et al[6] have shown that the regulatory region of theβ1-integrin genecontains two promoters, one distal and one proximal tandemly situated. The twotandemly promoter regions are very G + C-rich, and lack both a TATA box and a CAATbox .Each promoter drives the expression of a uniqueβ1 gene, and two mRNAs aresynthesized that share the same coding sequence but diverge in the complete 5′untranslated region. but the regulation mechanism in transcription level was still unclear.
HaCaT(Human adult skin keratinocytos ,HaCaT) cell line originates from normalhuman epidermal cells, which have the capacity to proliferate infinitely. Research hasshowed that after injection of HaCaT into subcutaneous skin of the nude mice, it coμlddifferentiate into epithelial tissues, with expression of special markers for differentiation[7].In addition,our previous study indicated that expression of integrinβ1 protein wassupressed by the transfection of siIntegrinβ1 vector. The growth curve of HaCaT cellsafter transfection was moved right forward, indicating that the proliferation of HaCaTcells was inhibited by the transfection[8]. As described above, HaCaT cell line can providean ideal model for the research of regulation of human epidermal cell proliferation.
Objective:
To explore the mechanism of regulation of integrinβ1 expression. HaCaT cells andluciferase reporter gene system containing integrinβ1 promoter were enrolled in our studyto investigate the influence of integrinβ1 on the proliferation and differentiation of humanepidermal cells.
Methods:
Dual-luciferase reporter vectors containing distal part and proximal part of integrinβ1 promoter were constructed successfully. Then they were transfected into HaCaT cellsto investigate their activity after transfection. This can help us to understand the role ofintegrinβ1 in the transcriptive regulation of HaCaT cells.
The main effect of promotor in transcriptional control was determined in accordingto the result in the first part. Tfsitescan software was used to analyze potential bindingsite of transcription factor in the promotor. Dissection and construction of mutationluciferase report gene vector with series deletion of promotor were carry out according toanalytic result. After sequencing, they were transfected into HaCaT cells, then the activityof luciferase was detected, and the activity of distal promoter of integrinβ1and potentialtranscriptional control factors participating possibly transcriptional control were analyzed.
Results:
We successfully amplified the whole length of integrinβ1 promoter from humangenome by PCR, and transfected the vector containing proximal ,distal and full part ofintegrinβ1 promoter into HaCaT cells. Analysis of luciferase activity revealed that thedistal part of promoter played an important role in the regulation of integrinβ1 transcripton.
In addition, we successfully constructed series deletion mutation luciferase reportgene vector of promotor:
pGL3-372,pGL3-392,pGL3-412,pGL3-432,pGL3-452,pGL3-492,p GL3-542, andtransfected the series vector into HaCaT cells. Analysis of luciferase activity revealed thatluciferase activity of pGL3-412,pGL3-432,pGL3-452,pGL3-492,p GL3-542 is higher thanpGL3-352 ,pGL3-372,pGL3-392.
Conclusion:
1. The luciferase activity of pGL3-352 ,pGL3-372,pGL3-392 is similar in HaCat.
2. The luciferase activity of pGL3-412,pGL3-432,pGL3-452,pGL3-492,p GL3-542 issimilar in HaCat .
3. The luciferase activity of pGL3-412,pGL3-432,pGL3-452,pGL3-492,p GL3-542 ishigher than pGL3-352 ,pGL3-372,pGL3-392 in HaCat.
4. In the integrinβ1 promoter sequences, the transcription factor binding initiationsite possibly is in 30bp located at between -686bp~-715bp in HaCat cells.
引文
1. Watt FM, Hogan BLM. Out of Eden: stem cells and their niches. Science, 2000, 287:1427-1430
2. Jones SM, Lowell S, Hutter C. Epidermal stem cells. J Pathol,2002,197:479-491
3. Brown EJ: Integrin-associated proteins. Curr Opin CellBiol 2002,14: 603–607.
4.唐红英,伍素华,罗向东,等整合素β1小RNA载体构建及其在表皮干细胞干扰效应检测[J].第三军医大学学报,2004,26(23)2120-2022
5. Piero C, Lorenzo S, Cristina P, et al. Humanβ1- Integrin Gene Expression isregμlated by two promoter regions. 1993,268(7),5148-5155
6. Petra B, Rμle T. P, Dirk B,Jiirgen H, al et Normal Keratinization in a pontaneouslyImmortalized Aneuploid Human Keratinocyte Cell Line .Eur J Cell Biol. 1988,106:762-771
7.闫德雄,苏踊跃,唐红英,等。整合素β1在人表皮细胞株HaCaT增殖中影响的研究。第三军医大学学报,2006,28(8)760-762。
8. Sieber-Blum M, Grim M. The adμlt hair follicle: cradle for pluripotent neural creststem cells. Birth Defects Res C Embryo Today. 2004 ,72(2):162-172.
9. Lavker RM, Sun TT, Oshima H, et al. Hair follicle stem cells. J Investig DermatolSymp Proc. 2003 ,8(1):28-38.
10. Liang L, Bickenbach JR. Somatic epidermal stem cells can produce mμltiple celllineages during development. Stem Cells. 2002; 20(1):21-31
11. 14、Taylor G; Lehrer MS,Jensen PJ,et al. Involvement of follicμlar stem cells informing not only the follicle but also the epidermis. Cell. 2000,102(4): 451-461
12. Graus-Porta D, Blaess S, Senften M, et al:β1-class integrins regμlate the developmentof laminae and folia in the cerebral and cerebellar cortex. Neuron 2001,31: 367–379.
13. Michno K, Boras-Granic K, Mill P, et al: Shh expression is required for embryonichair follicle but not mammary gland development. Dev. Biol 2003,264:153–165
14.司徒镇强,吴军正主编.细胞培养.第一版,北京:世界图书出版公司,1996.
15.黄培堂等译.细胞实验指南.北京:科学出版社,2001.
16. Black AR, Jensen D, Lin SY, Azizkhan JC. Growth/cell cycle regμlation of Sp1phosphorylation. J Biol Chem. 1999, 274: 1207-1215.
17. Eastman HB, Swick AG, Schmitt MC, Azizkhan JC. Stimμlation of dihydrofolatereductase promoter activity by antimetabolic drugs. Proc Natl Acad Sci USA. 1991,88: 8572-8576.
18. Li S, Harrison D, Carbonetto S, F¨assler R, Smyth N, Edgar D, Yurchenco PD:Matrix assembly, regμlation, and survival functions of laminin and its receptors inembryonic stem cell differentiation. J Cell Biol 157: 1279–1290, 2002.
19. Henry MD, Campbell KP: A role for dystroglycan in basement membrane assembly.Cell 95: 859–870, 1998.
20. Brakebusch C, Grose R, Quondamatteo F, et al: Skin and hair follicle integrity iscrucially dependent onβ1 integrin expression on keratinocytes. EMBO J 2000,19:3990–4003.
21. Raghavan S, Bauer C, Mundschau G, et al:Conditional ablation ofβ1 integrin in skin.Severe defects in epidermal proliferation, basement membrane formation,and hairfollicle invagination. J Cell Biol 2000,150: 1149–1160.
22. Weaver RF. Molecμlar biology.北京:科学出版社, 2002:279-290
23.朱玉贤,李毅.现代分子生物学.第2版.北京:高等教育出版社,2002:64-77
1. Brakebusch, C., F?ssler, R.,β1 integrin function in vivo: adhesion, migration andmore. Cancer Metastasis Rev. 2005.24, 403–411.
2. Liu S, CalderwoodDA, Ginsberg MH: Integrin cytoplasmic domain-binding proteins.J Cell Sci 2000,13: 3563–3571.
3. Brakebusch C, F¨assler R: The integrin-actin connection,an eternal love affair. EMBOJ 2003,22: 2324–2333
4. Brown EJ: Integrin-associated proteins. Curr Opin CellBiol 2002,14: 603–607.
5. Takashi Yasuda,Satoshi kondo,Toshio Hamma,el al.Regulation of extraceller matrixby mechancal stress in rat glomerular mesangral cells The Journal of ClinicalInvestigation.Volumn 98 Number 9,Novernber 1996;1991-2000
6. W.S. Marshall , F. Katoh, H.P. Main, N. Sers, R.R.F. Cozzi, Focal adhesion kinaseandβ1 integrin regulation of Na+, K+, 2Cl? cotransporter in osmosensing iontransporting cells of killifish, Fundulus heteroclitus,J. Comparative Biochemistry andPhysiology, Part A 150 (2008) 288–300
7. Ingber DE. Mechanobiology and diseases ofmechanotransduction[J]。Ann Med, 2003,35(8):564-577
8. Urbic C, Walter DH, Zeiher AH, et al. Laminar Shear Stress Upregulates IntegrinExpression Role in Endothelial Cell Adhesion and Apoptosis [J]。Circ Res, 2000,87(8): 683-689.
9. Lee DJ , Rosenfeldt H , Grinnell F. Activation of ERK and p38 MAP kinases inhuman fi2 broblasts during collagen matrix contraction. Exp Cell Res , 2000 , 257 :
190 - 197.
10. Wang N,Ingber DE.Probing transmembrane mechanical coupling andcytomechanicsusing magnetic twisting cytometry[J].Cell Biol,1995,73:327-335.
11. C. Radel, V. Rizzo, Integrin mechanotransduction stimulates caveolin-1phosphorylation and recruitment of Csk to mediate actinreorganization, Am. J.Physiol. Heart Circ. Physiol. 288 (2005) H936–H945.
12. Chris Radel, MaryEllen Carlile-Klusacek, Victor Rizzo,Participation of caveolae inb1 integrin-mediated mechanotransduction[J].Biochemical and Biophysical ResearchCommunications 358 (2007) 626–631
13. Juan Sanchez-Esteban,1 Yulian Wang,1 Edward J. Filardo, et al. Integrins _1, _6, and_3 contribute to mechanical strain-induced differentiation of fetal lung type IIepithelial cells via distinct mechanisms J Am J Physiol Lung Cell Mol Physiol290(2006): L343–L350,
14. J.C. Adams, F.M. Watt, Expression of beta 1, beta 3, beta 4, and beta 5 integrins byhuman epidermal keratinocytes and non-differentiating keratinocytes, J. Cell Biol. 115(1991) ,829–841.
15. W.G. Carter, P. Kaur, S.G. Gil, P.J. Gahr, E.A. Wayner, Distinct functions for integrinsalpha 3 beta 1 in focal adhesions and alpha 6 beta 4/bullous pemphigoid antigen in anew stable anchoring contact (SAC) of keratinocytes: relation to hemidesmosomes, J.Cell Biol. 111 (1990) 3141–3154.
16. F.M. Watt, Role of integrins in regulating epidermal adhesion, growth anddifferentiation, Embo J. 21 (2002) 3919–3926.
17. N.A. Hotchin, A. Gandarillas, F.M. Watt, Regulation of cell surface beta 1 integrinlevels during keratinocyte terminal differentiation, J. Cell Biol. 128 (1995) 1209–1219.
18. Brakebusch C, Grose R, Quondamatteo F, et al: Skin and hair follicle integrity iscrucially dependent onβ1 integrin expression on keratinocytes. EMBO J 2000,19:3990–4003.
19. Michno K, Boras-Granic K, Mill P, et al: Shh expression is required for embryonichair follicle but not mammary gland development. Dev. Biol 2003,264:153–165
20. Grose R, Hutter C, BlochW, et al:Acrucial role ofβ1 integrins for keratinocytemigration in vitro and during cutaneous wound repair. Development 2002,129:2303–2315
21. Tsutomu Fujimura , Shigeru Moriwaki, Genji Imokawa, Yoshinori Takema. Crucialrole of fibroblast integrins a2 and b1 in maintaining the structural and mechanicalproperties of the skin[J]. Journal of Dermatological Science (2007) 45, 45—53
22. Broberg A, Heino J. Integrin a2b1-dependent contraction of floating collagen gels andinduction of collagenase are inhibited by tyrosine kinase inhibitors. Exp Cell Res1996;228:29—35.
23. Gardner H, Broberg A, Pozzi A, Laato M, Heino J. Absence of integrin alpha1beta1in the mouse causes loss of feedback regulation of collagen synthesis in normal andwounded dermis. J Cell Sci 1999;112:263—72.
24. Dao MA, Hashino K, Kato I et al. Adhesion to fibronectin maintains regenerativecapacity during ex vivo culture and transduction of human hematopoietic stem andprogenitor cells. Blood 1998;92:4612– 4621.
25. SANDRA GOTTSCHLING, RAINER SAFFRICH, ANJA SECKINGER et al. HumanMesenchymal Stromal Cells Regulate Initial Self-Renewing Divisions ofHematopoietic Progenitor Cells by a 1-Integrin- Dependent Mechanism[J] StemCells 2007;25;798-806
26. Papayannopoulou T, Priestley GV, Nakamoto B et al. Molecular pathways in bonemarrow homing: Dominant role of 4 1 over 2-integrins and selectins. Blood2001;98:2403–2411.
27. Brakebusch C, Fillatreau S, Potocnik AJ, et al:β1 integrin is not essential forhematopoiesis but is necessary for the T cell-dependent IgM antibody response.Immunity.2002, 16: 465–477.
28. J. Rohwedel, K. Guan, W. Zuschratter, S. Jin, G. Ahnert-Hilger, D. Furst, R. Fassler,A.M. Wobus, Loss ofβ1 integrin function results in a retardation of myogenic, but anacceleration of neuronal, differentiation of embryonic stem cells in vitro, Dev. Biol.201 (1998) 167–184.
29. S. Crawley, E.M. Farrell, W. W, M. Gu, H.Y. Huang, V. Huynh, B.L. Hodges, D.N.Cooper, S.J. Kaufman, Theα7β1 integrin mediates adhesion and migration of skeletalmyoblasts on laminin, Exp. Cell Res. 235 (1997) 274–286.
30. M. Schwander, M. Leu, M. Stumm, O.M. Dorchies, U.T. Ruegg, J. Schittny, U.Muller,β1 Integrins regulate myoblast fusion and sarcomere assembly, Dev. Cell 4(2003) 673–685.
31. M.D. Boppart, D.J. Burkin, S.J. Kaufman,α7β1 Integrin regulatesmechanotransduction and prevents skeletal muscle injury, Am. J. Physiol.: CellPhysiol. 290 (2006) C1660–C1666.
32. M. Schwander, R. Shirasaki, S.L. Pfaff, U. Muller,β1 Integrins in muscle, but not inmotor neurons, are required for skeletal muscle innervation, J. Neurosci. 24 (2004)8181–8191.
33. Hirsch E, Lohikangas L, Gμllberg D, Johansson S, F¨assler R: Mouse myoblasts canfuse and form a normal sarcomere in the absence ofβ1 integrin expression. J Cell Sci111(1998): 2397–2409.
34. Janes SM, Watt FM. New roles for integrins in squamous-cell carcinoma. Nat RevCancer 2006;6:175–83.
35. Marie-France D’Onofrio a,1, Ste′phane Bre′zillon a,1, Thomas Baranek et al.Identification of b1 integrin as mediator of melanoma cell adhesion to lumican,J.Biochemical and Biophysical Research Communications 365 (2008) 266–272
36. Letícia N. Gama-de-Souza 1, Elaine Cyreno-Oliveira 1, Vanessa M. Freitas 1 et al.Adhesion and protease activity in cell lines from human salivary gland tumors areregulated by the laminin-derived peptide AG73, syndecan-1 andβ1 integrin, J.Matrix Biology 27 (2008) 402–419
37. Ghosh S, Johnson JJ, Sen R, Mukhopadhyay S, Liu Y, Zhang F,et al. Functionalrelevance of urinary-type plasminogen activator receptor-alpha3beta1 integrinassociation in proteinase regulatory pathways. J Biol Chem 2006;281:13021–9.
38. Kramer RH, Shen X, Zhou H. Tumor cell invasion and survival in head and neckcancer. Cancer Metastasis Rev 2005;24:35–45.
39. Giannelli G, Astigiano S, Antonaci S, Morini M, Barbieri O, Noonan DM, et al. Roleof the alpha3beta1 and alpha6beta4 integrins in tumor invasion. Clin Exp Metastasis2002;19: 217–23.
40. Owens DM, Watt FM. Influence of beta1 integrins on epidermal squamous cellcarcinoma formation in a transgenic mouse model: alpha3beta1, but not alpha2beta1,suppresses malignant conversion. Cancer Res 2001;61:5248–54.
41. Jin H, Varner J. Integrins: roles in cancer development and as treatment targets. Br JCancer 2004;90:561–5.
42. Stroeken PJ, van Rijthoven EA, Boer E, et al: Cytoplasmic domain mutants ofβ1integrin, expressed inβ1-knockout lymphoma cells, have distinct effects on adhesion,invasion and metastasis. Oncogene. 2000,19: 1232–1238.
43. White DE, Kurpios NA, Zuo D, et al: Targeted disruption ofβ1-integrin in atransgenic mouse model of human breast cancer reveals an essential role in mammarytumor induction .Cancer Cell.2004, 6: 159–170.
44. Balkwill F: Cancer and the chemokine network. Nat Rev Cancer2004, 4: 540–550.
45. Cardones AR, Murakami T, Hwang ST: CXCR4 enhances adhesion of B16 tumorcells to endothelial cells in vitro and in vivo viaβ1 integrin. Cancer Res 2003, 63:6751–6757.
2. Jones SM, Lowell S, Hutter C. Epidermal stem cells. J Pathol,2002,197:479-491
3. Brown EJ: Integrin-associated proteins. Curr Opin CellBiol 2002,14: 603–607.
4.唐红英,伍素华,罗向东,等整合素β1小RNA载体构建及其在表皮干细胞干扰效应检测[J].第三军医大学学报,2004,26(23)2120-2022
5. Piero C, Lorenzo S, Cristina P, et al. Humanβ1- Integrin Gene Expression isregμlated by two promoter regions. 1993,268(7),5148-5155
6. Petra B, Rμle T. P, Dirk B,Jiirgen H, al et Normal Keratinization in a pontaneouslyImmortalized Aneuploid Human Keratinocyte Cell Line .Eur J Cell Biol. 1988,106:762-771
7.闫德雄,苏踊跃,唐红英,等。整合素β1在人表皮细胞株HaCaT增殖中影响的研究。第三军医大学学报,2006,28(8)760-762。
8. Sieber-Blum M, Grim M. The adμlt hair follicle: cradle for pluripotent neural creststem cells. Birth Defects Res C Embryo Today. 2004 ,72(2):162-172.
9. Lavker RM, Sun TT, Oshima H, et al. Hair follicle stem cells. J Investig DermatolSymp Proc. 2003 ,8(1):28-38.
10. Liang L, Bickenbach JR. Somatic epidermal stem cells can produce mμltiple celllineages during development. Stem Cells. 2002; 20(1):21-31
11. 14、Taylor G; Lehrer MS,Jensen PJ,et al. Involvement of follicμlar stem cells informing not only the follicle but also the epidermis. Cell. 2000,102(4): 451-461
12. Graus-Porta D, Blaess S, Senften M, et al:β1-class integrins regμlate the developmentof laminae and folia in the cerebral and cerebellar cortex. Neuron 2001,31: 367–379.
13. Michno K, Boras-Granic K, Mill P, et al: Shh expression is required for embryonichair follicle but not mammary gland development. Dev. Biol 2003,264:153–165
14.司徒镇强,吴军正主编.细胞培养.第一版,北京:世界图书出版公司,1996.
15.黄培堂等译.细胞实验指南.北京:科学出版社,2001.
16. Black AR, Jensen D, Lin SY, Azizkhan JC. Growth/cell cycle regμlation of Sp1phosphorylation. J Biol Chem. 1999, 274: 1207-1215.
17. Eastman HB, Swick AG, Schmitt MC, Azizkhan JC. Stimμlation of dihydrofolatereductase promoter activity by antimetabolic drugs. Proc Natl Acad Sci USA. 1991,88: 8572-8576.
18. Li S, Harrison D, Carbonetto S, F¨assler R, Smyth N, Edgar D, Yurchenco PD:Matrix assembly, regμlation, and survival functions of laminin and its receptors inembryonic stem cell differentiation. J Cell Biol 157: 1279–1290, 2002.
19. Henry MD, Campbell KP: A role for dystroglycan in basement membrane assembly.Cell 95: 859–870, 1998.
20. Brakebusch C, Grose R, Quondamatteo F, et al: Skin and hair follicle integrity iscrucially dependent onβ1 integrin expression on keratinocytes. EMBO J 2000,19:3990–4003.
21. Raghavan S, Bauer C, Mundschau G, et al:Conditional ablation ofβ1 integrin in skin.Severe defects in epidermal proliferation, basement membrane formation,and hairfollicle invagination. J Cell Biol 2000,150: 1149–1160.
22. Weaver RF. Molecμlar biology.北京:科学出版社, 2002:279-290
23.朱玉贤,李毅.现代分子生物学.第2版.北京:高等教育出版社,2002:64-77
1. Brakebusch, C., F?ssler, R.,β1 integrin function in vivo: adhesion, migration andmore. Cancer Metastasis Rev. 2005.24, 403–411.
2. Liu S, CalderwoodDA, Ginsberg MH: Integrin cytoplasmic domain-binding proteins.J Cell Sci 2000,13: 3563–3571.
3. Brakebusch C, F¨assler R: The integrin-actin connection,an eternal love affair. EMBOJ 2003,22: 2324–2333
4. Brown EJ: Integrin-associated proteins. Curr Opin CellBiol 2002,14: 603–607.
5. Takashi Yasuda,Satoshi kondo,Toshio Hamma,el al.Regulation of extraceller matrixby mechancal stress in rat glomerular mesangral cells The Journal of ClinicalInvestigation.Volumn 98 Number 9,Novernber 1996;1991-2000
6. W.S. Marshall , F. Katoh, H.P. Main, N. Sers, R.R.F. Cozzi, Focal adhesion kinaseandβ1 integrin regulation of Na+, K+, 2Cl? cotransporter in osmosensing iontransporting cells of killifish, Fundulus heteroclitus,J. Comparative Biochemistry andPhysiology, Part A 150 (2008) 288–300
7. Ingber DE. Mechanobiology and diseases ofmechanotransduction[J]。Ann Med, 2003,35(8):564-577
8. Urbic C, Walter DH, Zeiher AH, et al. Laminar Shear Stress Upregulates IntegrinExpression Role in Endothelial Cell Adhesion and Apoptosis [J]。Circ Res, 2000,87(8): 683-689.
9. Lee DJ , Rosenfeldt H , Grinnell F. Activation of ERK and p38 MAP kinases inhuman fi2 broblasts during collagen matrix contraction. Exp Cell Res , 2000 , 257 :
190 - 197.
10. Wang N,Ingber DE.Probing transmembrane mechanical coupling andcytomechanicsusing magnetic twisting cytometry[J].Cell Biol,1995,73:327-335.
11. C. Radel, V. Rizzo, Integrin mechanotransduction stimulates caveolin-1phosphorylation and recruitment of Csk to mediate actinreorganization, Am. J.Physiol. Heart Circ. Physiol. 288 (2005) H936–H945.
12. Chris Radel, MaryEllen Carlile-Klusacek, Victor Rizzo,Participation of caveolae inb1 integrin-mediated mechanotransduction[J].Biochemical and Biophysical ResearchCommunications 358 (2007) 626–631
13. Juan Sanchez-Esteban,1 Yulian Wang,1 Edward J. Filardo, et al. Integrins _1, _6, and_3 contribute to mechanical strain-induced differentiation of fetal lung type IIepithelial cells via distinct mechanisms J Am J Physiol Lung Cell Mol Physiol290(2006): L343–L350,
14. J.C. Adams, F.M. Watt, Expression of beta 1, beta 3, beta 4, and beta 5 integrins byhuman epidermal keratinocytes and non-differentiating keratinocytes, J. Cell Biol. 115(1991) ,829–841.
15. W.G. Carter, P. Kaur, S.G. Gil, P.J. Gahr, E.A. Wayner, Distinct functions for integrinsalpha 3 beta 1 in focal adhesions and alpha 6 beta 4/bullous pemphigoid antigen in anew stable anchoring contact (SAC) of keratinocytes: relation to hemidesmosomes, J.Cell Biol. 111 (1990) 3141–3154.
16. F.M. Watt, Role of integrins in regulating epidermal adhesion, growth anddifferentiation, Embo J. 21 (2002) 3919–3926.
17. N.A. Hotchin, A. Gandarillas, F.M. Watt, Regulation of cell surface beta 1 integrinlevels during keratinocyte terminal differentiation, J. Cell Biol. 128 (1995) 1209–1219.
18. Brakebusch C, Grose R, Quondamatteo F, et al: Skin and hair follicle integrity iscrucially dependent onβ1 integrin expression on keratinocytes. EMBO J 2000,19:3990–4003.
19. Michno K, Boras-Granic K, Mill P, et al: Shh expression is required for embryonichair follicle but not mammary gland development. Dev. Biol 2003,264:153–165
20. Grose R, Hutter C, BlochW, et al:Acrucial role ofβ1 integrins for keratinocytemigration in vitro and during cutaneous wound repair. Development 2002,129:2303–2315
21. Tsutomu Fujimura , Shigeru Moriwaki, Genji Imokawa, Yoshinori Takema. Crucialrole of fibroblast integrins a2 and b1 in maintaining the structural and mechanicalproperties of the skin[J]. Journal of Dermatological Science (2007) 45, 45—53
22. Broberg A, Heino J. Integrin a2b1-dependent contraction of floating collagen gels andinduction of collagenase are inhibited by tyrosine kinase inhibitors. Exp Cell Res1996;228:29—35.
23. Gardner H, Broberg A, Pozzi A, Laato M, Heino J. Absence of integrin alpha1beta1in the mouse causes loss of feedback regulation of collagen synthesis in normal andwounded dermis. J Cell Sci 1999;112:263—72.
24. Dao MA, Hashino K, Kato I et al. Adhesion to fibronectin maintains regenerativecapacity during ex vivo culture and transduction of human hematopoietic stem andprogenitor cells. Blood 1998;92:4612– 4621.
25. SANDRA GOTTSCHLING, RAINER SAFFRICH, ANJA SECKINGER et al. HumanMesenchymal Stromal Cells Regulate Initial Self-Renewing Divisions ofHematopoietic Progenitor Cells by a 1-Integrin- Dependent Mechanism[J] StemCells 2007;25;798-806
26. Papayannopoulou T, Priestley GV, Nakamoto B et al. Molecular pathways in bonemarrow homing: Dominant role of 4 1 over 2-integrins and selectins. Blood2001;98:2403–2411.
27. Brakebusch C, Fillatreau S, Potocnik AJ, et al:β1 integrin is not essential forhematopoiesis but is necessary for the T cell-dependent IgM antibody response.Immunity.2002, 16: 465–477.
28. J. Rohwedel, K. Guan, W. Zuschratter, S. Jin, G. Ahnert-Hilger, D. Furst, R. Fassler,A.M. Wobus, Loss ofβ1 integrin function results in a retardation of myogenic, but anacceleration of neuronal, differentiation of embryonic stem cells in vitro, Dev. Biol.201 (1998) 167–184.
29. S. Crawley, E.M. Farrell, W. W, M. Gu, H.Y. Huang, V. Huynh, B.L. Hodges, D.N.Cooper, S.J. Kaufman, Theα7β1 integrin mediates adhesion and migration of skeletalmyoblasts on laminin, Exp. Cell Res. 235 (1997) 274–286.
30. M. Schwander, M. Leu, M. Stumm, O.M. Dorchies, U.T. Ruegg, J. Schittny, U.Muller,β1 Integrins regulate myoblast fusion and sarcomere assembly, Dev. Cell 4(2003) 673–685.
31. M.D. Boppart, D.J. Burkin, S.J. Kaufman,α7β1 Integrin regulatesmechanotransduction and prevents skeletal muscle injury, Am. J. Physiol.: CellPhysiol. 290 (2006) C1660–C1666.
32. M. Schwander, R. Shirasaki, S.L. Pfaff, U. Muller,β1 Integrins in muscle, but not inmotor neurons, are required for skeletal muscle innervation, J. Neurosci. 24 (2004)8181–8191.
33. Hirsch E, Lohikangas L, Gμllberg D, Johansson S, F¨assler R: Mouse myoblasts canfuse and form a normal sarcomere in the absence ofβ1 integrin expression. J Cell Sci111(1998): 2397–2409.
34. Janes SM, Watt FM. New roles for integrins in squamous-cell carcinoma. Nat RevCancer 2006;6:175–83.
35. Marie-France D’Onofrio a,1, Ste′phane Bre′zillon a,1, Thomas Baranek et al.Identification of b1 integrin as mediator of melanoma cell adhesion to lumican,J.Biochemical and Biophysical Research Communications 365 (2008) 266–272
36. Letícia N. Gama-de-Souza 1, Elaine Cyreno-Oliveira 1, Vanessa M. Freitas 1 et al.Adhesion and protease activity in cell lines from human salivary gland tumors areregulated by the laminin-derived peptide AG73, syndecan-1 andβ1 integrin, J.Matrix Biology 27 (2008) 402–419
37. Ghosh S, Johnson JJ, Sen R, Mukhopadhyay S, Liu Y, Zhang F,et al. Functionalrelevance of urinary-type plasminogen activator receptor-alpha3beta1 integrinassociation in proteinase regulatory pathways. J Biol Chem 2006;281:13021–9.
38. Kramer RH, Shen X, Zhou H. Tumor cell invasion and survival in head and neckcancer. Cancer Metastasis Rev 2005;24:35–45.
39. Giannelli G, Astigiano S, Antonaci S, Morini M, Barbieri O, Noonan DM, et al. Roleof the alpha3beta1 and alpha6beta4 integrins in tumor invasion. Clin Exp Metastasis2002;19: 217–23.
40. Owens DM, Watt FM. Influence of beta1 integrins on epidermal squamous cellcarcinoma formation in a transgenic mouse model: alpha3beta1, but not alpha2beta1,suppresses malignant conversion. Cancer Res 2001;61:5248–54.
41. Jin H, Varner J. Integrins: roles in cancer development and as treatment targets. Br JCancer 2004;90:561–5.
42. Stroeken PJ, van Rijthoven EA, Boer E, et al: Cytoplasmic domain mutants ofβ1integrin, expressed inβ1-knockout lymphoma cells, have distinct effects on adhesion,invasion and metastasis. Oncogene. 2000,19: 1232–1238.
43. White DE, Kurpios NA, Zuo D, et al: Targeted disruption ofβ1-integrin in atransgenic mouse model of human breast cancer reveals an essential role in mammarytumor induction .Cancer Cell.2004, 6: 159–170.
44. Balkwill F: Cancer and the chemokine network. Nat Rev Cancer2004, 4: 540–550.
45. Cardones AR, Murakami T, Hwang ST: CXCR4 enhances adhesion of B16 tumorcells to endothelial cells in vitro and in vivo viaβ1 integrin. Cancer Res 2003, 63:6751–6757.