Wright Casey W, Rumble Julie M, Duckett Colin S
Department of Pathology, the Molecular Mechanisms of Disease Program, University of Michigan, Ann Arbor, Michigan 48109, USA.
J Biol Chem. 2007 Apr 6;282(14):10252-62. doi: 10.1074/jbc.M608817200. Epub 2007 Jan 29.
CD30 is a member of the tumor necrosis factor receptor superfamily whose expression is up-regulated on anaplastic large cell lymphoma (ALCL) and Hodgkin lymphoma (HL) cells. Many different outcomes of CD30 stimulation have been reported, including cell cycle arrest, apoptosis, and activation of the prosurvival transcription factor, NF-kappaB, although this last activity is much less well defined in ALCL cells. In order to better understand the signaling properties of CD30 in cancer, we established a system for the stimulation of CD30 with its physiological ligand. Using this system, CD30 was stimulated on ALCL and HL cells, and the subsequent CD30 signaling properties were characterized. We show that a fraction of ALCL cells rapidly underwent apoptosis following CD30 stimulation, whereas HL cells were unaffected. The surviving ALCL cells exhibited robust activation of both the canonical and alternative NF-kappaB pathways as measured by nuclear translocation of RelA, p50, RelB, and p52, and this culminated in the transactivation of classical NF-kappaB-responsive genes. With prolonged CD30 stimulation, ALCL cells underwent cell cycle arrest that correlated with expression of the cell cycle inhibitor p21(waf1). Furthermore, p21(waf1) expression and cell cycle arrest were found to depend predominantly on the canonical NF-kappaB pathway, since it was reversed by RNA interference-mediated suppression of RelA. In contrast, suppression of the p100/p52 NF-kappaB subunit had little effect on p21(waf1). These data reveal that in ALCL cells, in contrast to other cell types, CD30 stimulation elicits p21(waf1)-mediated arrest through the canonical but not the alternative NF-kappaB pathway.
CD30是肿瘤坏死因子受体超家族的成员,其表达在间变性大细胞淋巴瘤(ALCL)和霍奇金淋巴瘤(HL)细胞上上调。已有许多关于CD30刺激的不同结果的报道,包括细胞周期停滞、凋亡以及促生存转录因子NF-κB的激活,尽管在ALCL细胞中最后这种活性的定义还不太明确。为了更好地理解CD30在癌症中的信号特性,我们建立了一个用其生理配体刺激CD30的系统。利用该系统,在ALCL和HL细胞上刺激CD30,并对随后的CD30信号特性进行了表征。我们发现,一部分ALCL细胞在CD30刺激后迅速发生凋亡,而HL细胞未受影响。通过RelA、p50、RelB和p52的核转位检测发现,存活的ALCL细胞表现出经典和替代NF-κB途径的强烈激活,这最终导致经典NF-κB反应性基因的反式激活。随着CD30刺激时间的延长,ALCL细胞发生细胞周期停滞,这与细胞周期抑制剂p21(waf1)的表达相关。此外,发现p21(waf1)的表达和细胞周期停滞主要依赖于经典NF-κB途径,因为RNA干扰介导的RelA抑制可使其逆转。相比之下,抑制p100/p52 NF-κB亚基对p21(waf1)影响很小。这些数据表明,在ALCL细胞中,与其他细胞类型不同,CD30刺激通过经典而非替代NF-κB途径引发p21(waf1)介导的停滞。