Heckmann Doreen, Laufs Stephanie, Maier Patrick, Zucknick Manuela, Giordano Frank A, Veldwijk Marlon R, Eckstein Volker, Wenz Frederik, Zeller W Jens, Fruehauf Stefan, Allgayer Heike
Molecular Oncology of Solid Tumors, DKFZ (German Cancer Research Center), Heidelberg, Germany.
Onkologie. 2011;34(10):502-8. doi: 10.1159/000332390. Epub 2011 Sep 20.
The development of distant metastasis is associated with poor outcome in patients with colorectal cancer (CRC). The stromal cell-derived factor-1 (SDF-1) and its receptor CXC chemokine receptor 4 (CXCR4) have pivotal roles in the chemotaxis of migrating tumor cells during metastasis. Thus, hampering the SDF-1/CXCR4 cross-talk is a promising strategy to suppress metastasis.
We investigated the invasive behavior of the lentivirally CXCR4 overexpressing CRC cell lines SW480, SW620 and RKO in chemotaxis and invasion assays toward an SDF-1α gradient. Low endogenous CXCR4 expression levels were determined by quantitative realtime polymerase chain reaction (PCR) and fluorescence-activated cell sorting (FACS) analyses.
A lentiviral CXCR4 overexpression and knockdown model was established in these CRC cells. In transwell migration assays, CXCR4 overexpression favored chemotaxis and invasion of cells in all 3 lines depending on an SDF-1α gradient (p < 0.001 vs. untransduced cells). Functional CXCR4 knockdown using lentiviral short hairpin RNA (shRNA) vectors significantly decreased the migration behavior in CRC cell lines (p < 0.001), confirming a CXCR4-specific effect. Pharmacologic inhibition of the SDF-1α/CXCR4 interaction by the bicyclam Plerixafor(TM) at 100 μM significantly abrogated CXCR4-dependent migration and invasion through Matrigel(TM) (SW480, SW620, RKO; p < 0.05).
Our results indicate that a CXCR4-antagonistic therapy might prevent tumor cell dissemination and metastasis in CRC patients, consequently improving survival.
远处转移的发生与结直肠癌（CRC）患者的不良预后相关。基质细胞衍生因子-1（SDF-1）及其受体CXC趋化因子受体4（CXCR4）在转移过程中肿瘤细胞迁移的趋化作用中起关键作用。因此，阻碍SDF-1/CXCR4相互作用是抑制转移的一种有前景的策略。
我们在趋化性和侵袭试验中，研究了慢病毒介导CXCR4过表达的CRC细胞系SW480、SW620和RKO对SDF-1α梯度的侵袭行为。通过定量实时聚合酶链反应（PCR）和荧光激活细胞分选（FACS）分析确定内源性CXCR4表达水平较低。
在这些CRC细胞中建立了慢病毒介导的CXCR4过表达和敲低模型。在Transwell迁移试验中，CXCR4过表达有利于所有3个细胞系中的细胞趋化和侵袭，这取决于SDF-1α梯度（与未转导细胞相比，p < 0.001）。使用慢病毒短发夹RNA（shRNA）载体进行功能性CXCR4敲低显著降低了CRC细胞系中的迁移行为（p < 0.001），证实了CXCR4特异性效应。双环胺普乐沙福（Plerixafor™）在100 μM时对SDF-1α/CXCR4相互作用的药理抑制显著消除了通过基质胶（Matrigel™）的CXCR4依赖性迁移和侵袭（SW480、SW620、RKO；p < 0.05）。
我们的结果表明，CXCR4拮抗疗法可能预防CRC患者的肿瘤细胞播散和转移，从而提高生存率。
