Lian Xin, Jiao Yu, Yang Yu, Wang Zhipeng, Xuan Qijia, Liu Hang, Lu Shan, Wang Zunxian, Liu Yue, Li Shuo, Yang Yuguang, Guo Li, Zhao Ling, Zhang Qingyuan
Department of Medical Oncology, The Third Affiliated Hospital of Harbin Medical University, Haping Road 150 of Nangang District, Harbin, 150081, Heilongjiang, China.
Med Oncol. 2015 Jan;32(1):411. doi: 10.1007/s12032-014-0411-z. Epub 2014 Dec 5.
The adapter protein CrkL is required for regulating the malignant potential of human cancers. However, the regulatory mechanisms of CrkL on the stromal cell-derived factor 1 (SDF-1)/CXCR4 signaling pathways in breast cancer are not well characterized. Here, CXCR4 and CrkL proteins were tested in breast cancer cell lines and 60 primary breast cancer tissues. In vitro, the roles of CrkL in SDF-1-induced MDA-MB-231 cell cycle, invasion and migration were investigated. In the present study, CXCR4 and CrkL were highly expressed in MCF-7, MDA-MB-231, MDA-MB-231HM MDA-MB-468 and tumor tissues (80 and 60 %, respectively) and closely correlated with lymph node metastasis. In vitro studies revealed that SDF-1 induced the activation of CrkL, Erk1/2, Akt and matrix metallopeptidase 9 (MMP9) in MDA-MB-231 cells. The si-CrkL treatment significantly down-regulated the phosphorylated Erk1/2 (p-Erk1/2) and MMP9, but up-regulated p-Akt, compared with control. Importantly, wound-healing and transwell invasion assays showed that si-CrkL significantly impaired the wound closure and inhibited the SDF-1-induced invasion; similarly, flow cytometry showed that si-CrkL affected cell cycle. In conclusion, these results suggest that CrkL plays a regulatory role in the SDF-1-induced Erk1/2 and PI3K/Akt pathways and further managed the invasion and migration of breast cancer cells. Thus, CrkL may be recommended as an interesting therapeutic target for breast cancer.
衔接蛋白CrkL是调节人类癌症恶性潜能所必需的。然而，CrkL对乳腺癌中基质细胞衍生因子1（SDF-1）/CXCR4信号通路的调节机制尚未完全明确。在此，对乳腺癌细胞系和60例原发性乳腺癌组织中的CXCR4和CrkL蛋白进行了检测。在体外，研究了CrkL在SDF-1诱导的MDA-MB-231细胞周期、侵袭和迁移中的作用。在本研究中，CXCR4和CrkL在MCF-7、MDA-MB-231、MDA-MB-231HM、MDA-MB-468细胞系及肿瘤组织中高表达（分别为80%和60%），且与淋巴结转移密切相关。体外研究显示，SDF-1可诱导MDA-MB-231细胞中CrkL、Erk1/2、Akt和基质金属蛋白酶9（MMP9）的激活。与对照组相比，si-CrkL处理显著下调了磷酸化的Erk1/2（p-Erk1/2）和MMP9，但上调了p-Akt。重要的是，伤口愈合和Transwell侵袭实验表明，si-CrkL显著损害伤口闭合，并抑制SDF-1诱导的侵袭；同样，流式细胞术显示si-CrkL影响细胞周期。总之，这些结果表明CrkL在SDF-1诱导的Erk1/2和PI3K/Akt信号通路中发挥调节作用，并进一步调控乳腺癌细胞的侵袭和迁移。因此，CrkL可能是一个有前景的乳腺癌治疗靶点。
