Inactivation of Rho GTPases by p190 RhoGAP reduces human pancreatic cancer cell invasion and metastasis
Inactivation of Rho GTPases by p190 RhoGAP reduces human pancreatic cancer cell invasion and metastasis
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DOI：
10.1111/j.1349-7006.2006.00242.x
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发表时间：
2006-09-01
期刊：
影响因子：
5.7
通讯作者：
Inoue, Masahiro
中科院分区：
文献类型：
--
作者：
Kusama, Toshiyuki;Mukai, Mutsuko;Inoue, Masahiro
许多小的GTP酶参与癌细胞的增殖、迁移和侵袭，充当分子开关，在GTP和GDP结合状态之间循环。GTP酶激活蛋白(GAP)是Rho GTP酶信号的一类主要负调控因子。为了探讨p190 RhoGAP对RhoA在癌细胞侵袭转移中的生物学作用，我们构建了p190的RhoGAP结构域与RhoA的C末端的嵌合体(p190-RhoA嵌合体)，并将其导入人胰腺癌细胞ASPC-1。通过GTP结合的RhoA、RhoB和RhoC的下拉实验表明，在p190-RhoA嵌合体转染的ASPC-1细胞中，表皮生长因子(EGF)诱导的RhoA、RhoB和RhoC的激活与对照细胞(模拟感染细胞)相比受到较小程度的抑制。在改良的Boyden小室实验中，与模拟感染细胞相比，EGF诱导的p190-RhoA嵌合体细胞的侵袭受到显著抑制。此外，脾内注射过表达p190-RhoA嵌合体的ASPC-1细胞的小鼠，肝脏转移结节的数量和大小显著减少。这些数据表明，p190 RhoGAP对RhoA的抑制作用为治疗癌细胞的侵袭和转移提供了一条新的途径。
A number of small GTPases are involved in cancer cell proliferation, migration and invasion, acting as molecular switches that cycle between GTP- and GDP-bound states. GTPase-activating proteins (GAPs) have been established as a major class of negative regulators of Rho GTPase signaling. To investigate the biological function of p190 RhoGAP toward RhoA in cancer cell invasion and metastasis, we generated a chimera made of the RhoGAP domain of p190 and the C-terminus of RhoA (p190-RhoA chimera), and transfected it into human pancreatic cancer cells, AsPC-1. Epidermal growth factor (EGF)-induced activation of RhoA, as well as RhoB and RhoC, to a lesser extent, was significantly inhibited in p190-RhoA chimera-transfected AsPC-1 cells compared with that of control cells (mock-infected), when assessed by pull-down assay for GTP-bound RhoA, RhoB, and RhoC, respectively. EGF-induced invasion of p190-RhoA chimera transfectants was significantly inhibited compared with that of mock-infected cells in a modified Boyden chamber assay. Furthermore, the mice injected intrasplenically with AsPC-1 cells that overexpressed the p190-RhoA chimera had a marked reduction in the number and size of metastatic nodules in the liver. These data suggest that the inhibitory action of p190 RhoGAP toward RhoA offers a novel approach to the treatment of invasion and metastasis of cancer cells.