公开(公告)号：US05998600A

公开(公告)日：1999-12-07

申请号：US3687

申请日：1998-01-07

申请人： Nick Barker ,  Hans Clevers ,  Vladimar Korinek

发明人： Nick Barker ,  Hans Clevers ,  Vladimar Korinek

IPC分类号： G01N33/50 ,  A61K31/711 ,  A61K38/00 ,  A61K48/00 ,  A61P35/00 ,  C07K14/47 ,  C12N15/09 ,  C12N15/12 ,  C12Q1/68 ,  G01N33/15

CPC分类号： C07K14/47 ,  C07K14/4705 ,  C12Q1/6897 ,  A61K38/00 ,  A61K48/00

摘要： The APC tumor suppressor protein binds to .beta.-catenin, a protein recently shown to interact with Tcf/Lef transcription factors. Here, the gene encoding a Tcf family member that is expressed in colonic epithelium (hTcf-4) a was cloned and characterized. hTcf-4 transactivates transcription only when associated with .beta.-catenin. Nuclei of APC.sup.-/- colon carcinoma cells were found to contain a stable .beta.-catenin-hTCF-4 complex that was constitutively active, as measured by transcription of a Tcf reporter gene. Reintroduction of APC removed .beta.-catenin from hTcf4 and abrogated the transcriptional transactivation. Constitutive transcription of TCF target genes, caused by loss of APC function, may be a crucial event in the early transformation of colonic epithelium. It is also shown here that the products of mutant APC genes found in colorectal tumors are defective in regulating .beta.-catenin/Tcf-4 transcrpitional activation. Furthermore, colorectal tumors with intact APC genes were shown to contain subtle activating mutations of .beta.-catenin that altered functionally significant phosphorylation sites. These results indicate that regulation of .beta.-catenin is critical to APC's tumor suppressive effect and that this regulation can be circumvented by mutations in either APC or .beta.-catenin.

摘要翻译： APC肿瘤抑制蛋白结合β-连环蛋白，最近显示出与Tcf / Lef转录因子相互作用的蛋白质。 这里，克隆并表征编码在结肠上皮（hTcf-4）a中表达的Tcf家族成员的基因。 hTcf-4仅在与β-连环蛋白相关时才转录转录。 发现APC - / - 结肠癌细胞的核含有稳定的β-联蛋白-hTCF-4复合物，其通过Tcf报道基因的转录测量而具有组成型活性。 重新引入APC从hTcf4中除去β-连环蛋白，并废除转录反式激活。 由APC功能丧失引起的TCF靶基因的组成转录可能是结肠上皮早期转化的关键事件。 这里还显示，在结肠直肠肿瘤中发现的突变APC基因的产物在调节β-连环蛋白/ Tcf-4跨刺激激活中是有缺陷的。 此外，具有完整APC基因的结肠直肠肿瘤显示含有改变功能显着磷酸化位点的β-连环蛋白的微妙活化突变。 这些结果表明，β-连环蛋白的调节对于APC的肿瘤抑制作用至关重要，并且该调节可以通过APC或β-连环蛋白的突变来规避。

公开(公告)号：US5851775A

公开(公告)日：1998-12-22

申请号：US821355

申请日：1997-03-20

申请人： Nick Barker ,  Hans Clevers ,  Kenneth W. Kinzler ,  Vladimer Korinek ,  Patrice J. Morin ,  Andrew B. Sparks ,  Bert Vogelstein

发明人： Nick Barker ,  Hans Clevers ,  Kenneth W. Kinzler ,  Vladimer Korinek ,  Patrice J. Morin ,  Andrew B. Sparks ,  Bert Vogelstein

IPC分类号： G01N33/50 ,  A61K31/711 ,  A61K38/00 ,  A61K48/00 ,  A61P35/00 ,  C07K14/47 ,  C12N15/09 ,  C12N15/12 ,  C12Q1/68 ,  G01N33/15 ,  G01N33/53

CPC分类号： C07K14/47 ,  C07K14/4705 ,  C12Q1/6897 ,  A61K38/00 ,  A61K48/00

摘要： The APC tumor suppressor protein binds to .beta.-catenin, a protein recently shown to interact with Tcf/Lef transcription factors. Here, the gene encoding a Tcf family member that is expressed in colonic epithelium (hTcf-4) was cloned and characterized. hTcf-4 transactivates transcription only when associated with .beta.-catenin. Nuclei of APC.sup.-/- colon carcinoma cells were found to contain a stable .beta.-catenin-hTCF-4 complex that was constitutively active, as measured by transcription of a Tcf reporter gene. Reintroduction of APC removed .beta.-catenin from hTcf4 and abrogated the transcriptional transactivation. Constitutive transcription of TCF target genes, caused by loss of APC function, may be a crucial event in the early transformation of colonic epithelium. It is also shown here that the products of mutant APC genes found in colorectal tumors are defective in regulating .beta.-catenin/Tcf-4 transcrpitional activation. Furthermore, colorectal tumors with intact APC genes were shown to contain subtle activating mutations of .beta.-catenin that altered functionally significant phosphorylation sites. These results indicate that regulation of .beta.-catenin is critical to APC's tumor suppressive effect and that this regulation can be circumvented by mutations in either APC or .beta.-catenin.

摘要翻译： APC肿瘤抑制蛋白结合β-连环蛋白，最近显示出与Tcf / Lef转录因子相互作用的蛋白质。 这里，克隆并表征编码在结肠上皮（hTcf-4）中表达的Tcf家族成员的基因。 hTcf-4仅在与β-连环蛋白相关时才转录转录。 发现APC - / - 结肠癌细胞的核含有稳定的β-联蛋白-hTCF-4复合物，其通过Tcf报道基因的转录测量而具有组成型活性。 重新引入APC从hTcf4中除去β-连环蛋白，并废除转录反式激活。 由APC功能丧失引起的TCF靶基因的组成转录可能是结肠上皮早期转化的关键事件。 这里还显示，在结肠直肠肿瘤中发现的突变APC基因的产物在调节β-连环蛋白/ Tcf-4跨刺激激活中是有缺陷的。 此外，具有完整APC基因的结肠直肠肿瘤显示含有改变功能显着磷酸化位点的β-连环蛋白的微妙活化突变。 这些结果表明，β-连环蛋白的调节对于APC的肿瘤抑制作用至关重要，并且该调节可以通过APC或β-连环蛋白的突变来规避。