MECHANISTIC STUDY OF APOPTOTIC CELL DEATH AND INVASION POTENTIAL USING SIGNAL TRANSDUCTION INHIBITORS IN THE ONCOGENE-TRANSFECTED HUMAN CELLS

使用信号转导抑制剂对转染癌基因的人类细胞进行凋亡细胞死亡和侵袭潜力的机制研究

基本信息

批准号：
10670415
负责人：
NAKANO Shuji
金额：
$ 2.11万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10670415/
关键词：
Oncogene apoptosis signal transductione Focal adhesion kinase Rac Rho loss of anchorage-dependence Src tyrosine kinase Ras rac rho ras

项目摘要

Although src or ras oncogene induces transformation, their precise roles in the apoptotic machinery and invasion remain to be clarified. We examined the role of these oncogenes on the detachment-induced apoptosis termed anoikis and invasion potential, using HAG-1 human epithelial cell lines transfected with v-src or activated ras. Non-tumorigenic parental, mock-transfected, and ras-transfected HAG-1 cells underwent anoikis. By contrast, tumorigenic, v-src-transformed cells did not exhibit such apoptotic features. pp125^<FAK> focal adhesion kinase (FAK), was constitutively activated only in the v-src-transformed cells. Moreover, herbimycin A, a Src tyrosine kinase inhibitor, reduced tyrosyl phosphorylation of pp125^<FAK>, and reversed resistance to anoikis. These data suggest that pp60^<v-src> may substitute for integrin in the activation of pp125^<FAK>, thereby evading anoikis, and that the association of pp60^<src> with FAK might be required for acquisition of anchorage-independence. … More The functional role of ras in the acquisition of fully neoplastic potentials by v-src-transformed human gallbladder HAG/src3-1 cells, were investigated by introducing adenoviral vector containing dominant negative Ras (DN/Ras) into these cells. The anchorage-independent growth of the HAG/src3-1 was inhibted by DN/Ras by 93%. The HAG/src3-1 cells transfected with DN/ras failed to form tumors. Thus, v-src might requires a Ras-MAP kinase signaling cascade in the acquisition of tumorigenic potential. To examine the potential role of Rac, a small GTPase binding protein which acts downstream of Ras, experiments using adenovirus vectors containing DN/Ras or dominant negative Rac (DN/Rac), were performed. The data indicated that both DN/Ras and DN/Rac reduced the invasive potential of src-transfected cells by 60% and 99%, respectively, as compared to AdCALacZ containing β-gal gene as a control. Moreover, DN/Rac suppressed completely the tumorigenic potentials of src-transfected cells in nude mice. These results suggest that Src, Ras, Rac, all appeared to participate in the invasion processes, and that Rac may act downstream of these signaling pathways of invasion and tumorigenicity. Less

尽管 src 或 ras 癌基因诱导转化，但它们在细胞凋亡机制和侵袭中的确切作用仍有待阐明。我们使用转染的 HAG-1 人上皮细胞系检查了这些癌基因对称为失巢凋亡的脱离诱导细胞凋亡和侵袭潜力的作用。使用 v-src 或激活的 ras，非致瘤性亲本、模拟转染和 ras 转染的 HAG-1 细胞在失巢凋亡中存活。相比之下，致瘤性、v-src-转化的细胞不表现出这样的凋亡特征，pp125^<FAK>粘着斑激酶(FAK)仅在v-src-转化的细胞中被组成型激活。此外，除草霉素A（一种Src酪氨酸）。激酶抑制剂，减少 pp125^<FAK> 的酪氨酰磷酸化，并逆转对失巢凋亡的抵抗力。 pp60^<v-src> 可以在 pp125^<FAK> 的激活中替代整合素，从而避免失巢凋亡，并且 pp60^<src> 与 FAK 的关联可能是获得锚定独立性所必需的……更多ras 在 v-src 转化的人胆囊 HAG/src3-1 细胞获得完全肿瘤潜能中的功能作用，通过引入将含有显性失活 Ras (DN/Ras) 的腺病毒载体导入这些细胞中，DN/Ras 抑制 HAG/src3-1 的贴壁依赖性生长 93%，转染 DN/ras 的 HAG/src3-1 细胞失败。因此，v-src 可能需要 Ras-MAP 激酶信号级联才能获得致瘤潜力，以检查 Rac（一种小型 GTP 酶）的潜在作用。使用含有 DN/Ras 或显性失活 Rac (DN/Rac) 的腺病毒载体进行实验，数据表明 DN/Ras 和 DN/Rac 均降低了 src 转染细胞的侵袭潜力。与作为对照的含有β-gal基因的AdCALacZ相比，DN/Rac分别降低了60%和99%。此外，DN/Rac完全抑制了其致瘤潜力。这些结果表明Src、Ras、Rac似乎都参与了侵袭过程，并且Rac可能在这些侵袭和致瘤性信号通路的下游发挥作用。