权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

REGULATORY MECHANISM OF RANKL GENE EXPRESSION

RANKL基因表达的调控机制

基本信息

批准号：
14570188
负责人：
KITAZAWA Riko
金额：
$ 2.3万
依托单位：
KOBE UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2003
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14570188/
关键词：
osteoclast RANKL gene promoter Vitamin D cAMP responsive element CpG methylation cAMP応答配列

项目摘要

Osteoclast differentiation factor (RANKL) is requisite for the formation and maintenance of osteoclasts from hematopoietic precursors. To clarify the mechanism of RANKL gene expression and osteoclastogenesis, mouse and human RANKL gene promoters were characterized. Both human and mouse RANKL gene promoter shares the common structure, inverted-TATA and CAAT boxes, Runx2/Cbfa-1 binding sites and vitamin D responsive element (VDRE). To elucidate the molecular mechanism of osteolytic bone metastasis, we assessed RANKL gene expression and osteoclastogenesis in osteolytic lesions of mouse experimental model and human bone specimen taken at the autopsy. In both mouse and human osteolytic lesion due to cancer metastasis, RANKL expression was observed on the stromal/osteoblastic cells close to the cancer cell nests. In the mouse model, PTHrP-producing tumor generated osteolytic lesion, whereas non-producing tumor rarely caused RANKL expression and induction of osteoclasts. We further analyzed the effects of PTHrP on RANKL gene transcription. By transient transfection studies using deletion constructs of mouse and human RANKL gene promoter, PTHrP upregulated the transcriptional activity through c-AMP responsive element (CRE) located close to VDRE in both mouse and human. EMSA showed specific protein DNA binding, and the supershift with anti-CREB1 and -ATF2 antibodies. Thus PTHrP induces osteoclastic bone resorption through the RANKL expression on stromal/osteoblastic cells, affording a bone microenvironment conducive to the survival of PTHrP-producing cancer cells.We have presented our data at various international as well as domestic meeting, and published scientific papers for academic journals.

破骨细胞分化因子(RANKL)是由造血祖细胞形成和维持破骨细胞所必需的。为了阐明RANKL基因表达和破骨细胞形成的机制，对小鼠和人RANKL基因启动子进行了鉴定。人和小鼠RANKL基因启动子具有共同的结构、倒转TATA和CAAT盒、Runx2/CBFA-1结合位点和维生素D反应元件(VDRE)。为了阐明溶骨性骨转移的分子机制，我们检测了RANKL基因在小鼠溶骨性病变中的表达和破骨细胞的形成，并在尸检中采集了人骨标本。在肿瘤转移所致的溶骨性病变中，RANKL在靠近癌巢的基质/成骨细胞上均有表达。在小鼠模型中，产生PTHrP的肿瘤产生溶骨损伤，而不产生肿瘤的肿瘤很少引起RANKL的表达和诱导破骨细胞。我们进一步分析了PTHrP对RANKL基因转录的影响。通过瞬时转染小鼠和人RANKL基因启动子的缺失结构，PTHrP通过位于VDRE附近的c-AMP反应元件(CRE)上调RANKL基因在小鼠和人中的转录活性。EMSA显示特异性蛋白DNA结合，并与抗CREB1和-ATF2抗体发生超位移位。因此，PTHrP通过在基质/成骨细胞上表达RANKL来诱导破骨细胞性骨吸收，为产生PTHrP的癌细胞提供了有利于生存的骨微环境。我们在各种国际和国内会议上发表了我们的数据，并在学术期刊上发表了科学论文。