CXC Receptor-1 Silencing Inhibits Androgen-Independent Prostate Cancer
CXC Receptor-1 Silencing Inhibits Androgen-Independent Prostate Cancer
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DOI：
10.1158/0008-5472.can-09-0374
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发表时间：
2009-11-01
期刊：
影响因子：
11.2
通讯作者：
Lokeshwar, Bal L.
中科院分区：
文献类型：
--
作者：
Shamaladevi, Nagarajarao;Lyn, Dominic A.;Lokeshwar, Bal L.
CXC受体-1（CXCR 1）是白细胞介素-8（IL-8）的辅助受体，在正常细胞和肿瘤细胞上均有表达。CXCR 1在前列腺癌中的功能通过使用RNA干扰沉默其表达来研究。我们建立了稳定的PC-3细胞的细胞集落，耗尽CXCR 1，使用慢病毒质粒（pLK0.1puro）产生针对CXCR 1 mRNA的小发夹RNA（shRNA）。表征了表达显著降低的CXCR 1 mRNA（>= 90%下降）和蛋白质（>= 43%下降）的稳定shRNA转染子（PLK 1-PLK 5）或仅载体转染子（PC-3V）。与PC-3V细胞相比，PLK细胞表现出细胞增殖减少（下降，>= 66%），这是由于细胞周期停滞在G（1）-S期，细胞周期蛋白D1、CDK 4、磷酸化Rb和细胞外信号调节激酶1/2水平降低。CXCR 1的描述导致自发性凋亡的增加，通过ESTA介导的内在机制和增加促凋亡蛋白（BAD，40%; BAX，12%），但减少抗凋亡蛋白（BCL 2，下降38%; BCLxL，20%）。PLK 2细胞生长为缓慢生长的肿瘤（减少54%），与无胸腺小鼠中的PC 3V肿瘤相比。PLK 2肿瘤组织的体外分析显示细胞周期蛋白D1和血管内皮生长因子的表达减少，细胞凋亡活性增加。当通过CXCR 1 shRNA转染耗尽CXCR 1时，其他表达IL-8的前列腺癌细胞系也表现出相似的表型。与这些细胞相反，CXCR 1耗竭对IL-8配体缺陷的LNCaP细胞几乎没有影响。使用突变的CXCR 1质粒的RNA干扰拯救逆转了PLK 2的沉默效应，从而证明了CXCR 1 shRNA的表型改变的特异性。这些研究证实CXCR 1促进IL-8介导的肿瘤生长。[Cancer Res 2009;69（2，1）：8265-74]
The CXC receptor-1 (CXCR1) is a coreceptor for interleukin-8 (IL-8) and is expressed on both normal and tumor cells. The function of CXCR1 in prostate cancer was investigated by silencing its expression, using RNA interference. We established stable cell colonies of PC-3 cells, depleted of CXCR1, using lentiviral plasmids (pLK0.1puro) generating small hairpin RNA (shRNA) against CXCR1 mRNA. Stable shRNA transfectants (PLK1-PLK5) that express significantly reduced CXCR1 mRNA (>= 90% down) and protein (>= 43% down) or vector-only transfectants (PC-3V) were characterized. PLK cells showed reduced cell proliferation (down, >= 66%), due to cell cycle arrest at G(1)-S phase, decreases in Cyclin D1, CDK4, phosphorylated Rb, and extracellular signal-regulated kinase 1/2 levels compared with those in PC-3V cells. CXCR1 depiction lead to increases in spontaneous apoptosis by mitochondria-mediated intrinsic mechanism and increases in proapoptotic proteins (BAD, 40%; BAX, 12%), but decreases in antiapoptotic proteins (BCL2, down 38%; BCLxL, 20%). PLK2 cells grew as slow-growing tumors (decrease of 54%), compared with that of PC3V tumors in athymic mice. Ex vivo analyses of PLK2 tumor tissues showed reduced expression of Cyclin D1 and vascular endothelial growth factor, and increased apoptosis activity. Other IL-8-expressing prostate cancer cell lines also exhibited similar phenotypes when CXCR1 was depleted by CXCR1 shRNA transfection. In contrast to these cells, CXCR1 depletion had little effect on IL-8 ligand-deficient LNCaP cells. RNA interference rescue using mutated CXCR1 plasmids reversed the silencing effect of PLK2, thus demonstrating the specificity of phenotypic alteration by CXCR1 shRNA. These studies establish that CXCR1 promotes IL-8-mediated tumor growth. [Cancer Res 2009;69(2,1):8265-74]