Requirement for Arf6 in breast cancer invasive activities
Requirement for Arf6 in breast cancer invasive activities
复制标题
DOI：
10.1073/pnas.0401753101
复制
发表时间：
2004-04-27
影响因子：
11.1
通讯作者：
Sabe, H
中科院分区：
文献类型：
--
作者：
Hashimoto, S;Onodera, Y;Sabe, H
在大多数人乳腺癌细胞系中，它们的体内侵袭表型和体外侵袭活性之间存在直接相关性。在此，我们发现ADP-核糖基化因子6（Arf 6）定位于培养的乳腺癌细胞MDA-MB-231的侵袭伪足，并且其被小干扰RNA双链体抑制有效地阻断了细胞的侵袭活动，例如侵袭伪足形成、局部基质降解和基质胶迁移，但不阻断细胞粘附活性。我们还发现，GTP水解缺陷突变体Arf6（Q67 L）和GTP结合缺陷突变体Arf6（T27 N）都阻断了这些侵入活动，但不细胞粘附，这表明在入侵中持续激活和循环Arf6 GTP酶循环的必要性。在我们研究的不同的人乳腺癌细胞系中，具有高侵袭活性的细胞系表达的Arf 6蛋白量高于弱侵袭性和非侵袭性细胞系，尽管在Arf 6 mRNA表达水平和侵袭活性之间没有发现显着的相关性。此外，所有这些侵入性细胞的基质胶迁移活性被Arf6小干扰RNA双链体有效地阻断。因此，Arf 6似乎是乳腺癌侵袭活动的一个组成部分，我们建议，Arf 6和细胞内机制调节Arf 6在入侵期间应被视为预防乳腺癌侵袭的治疗靶点。
in most human breast cancer cell lines, there is a direct correlation between their in vivo invasive phenotypes and in vitro invasion activities. Here, we found that ADP-ribosylation factor 6 (Arf6) is localized at the invadopodia of the cultured breast cancer cells MDA-MB-231, and its suppression by a small-interfering RNA duplex effectively blocks the invasive activities of the cells, such as invadopodia formation, localized matrix degradation and Matrigel transmigration but not the cell-adhesion activity. We also found that the GTP hydrolysis-defective mutant Arf6(Q67L) and the GTP-binding defective mutant Arf6(T27N) both blocked these invasive activities but not cell adhesion, suggesting the necessity of continued activation and cycling of the Arf6 GTPase cycle in invasion. Among the different human breast cancer cell lines that we examined, cell lines with high invasive activities expressed higher amounts of Arf6 protein than those in weakly invasive and noninvasive cell lines, although no notable correlation was found between Arf6 mRNA expression levels and invasive activities. Moreover, Matrigel-transmigration activity of all of these invasive cells was blocked effectively by an Arf6 small-interfering RNA duplex. Hence, Arf6 appears to be an integral component of breast cancer invasive activities, and we propose that Arf6 and the intracellular machinery regulating Arf6 during invasion should be considered as therapeutic targets for the prevention of breast cancer invasion.