Miyamoto Chihiro, Maehata Yojiro, Motohashi Kazuhiko, Ozawa Shigeyuki, Ikoma Takeharu, Hidaka Kouki, Wada-Takahashi Satoko, Takahashi Shun-Suke, Yoshino Fumihiko, Yoshida Ayaka, Kubota Eiro, Hata Ryu-Ichiro, Lee Masaichi-Chang-il
Department of Oral Science, Graduate School, Kanagawa Dental University; Oral Health Science Research Center, Japan.
Biomed Res. 2014;35(6):381-8. doi: 10.2220/biomedres.35.381.
CXCL14/BRAK (BRAK) is a secreted chemokine with anti-tumor activity, and its expression is suppressed in tumor cells. We previously reported the anti-tumor activity of BRAK in cell lines of head and neck squamous cell carcinoma (HNSCC) and the suppression of BRAK secretion in these cells. BRAK secretion in fibrosarcoma cells is restored by Fasudil, which is a Rho-kinase (ROCK) inhibitor. In this study, we examined the anti-tumor effect of BRAK by evaluating its gene expression and protein secretion in HNSCC cell lines. We found that BRAK mediated the suppressive effect of Fasudil against HNSCC cells. Tumor development in female BALB/cAJclnu/nu mice was suppressed by Fasudil. Also secretion of BRAK protein by tumor cell lines in vitro was significantly stimulated by Fasudil treatment. Similarly, the production of BRAK protein was significantly increased by the addition of Fasudil to cultured tumor cells. Furthermore Fasudil significantly increased BRAK gene expression at the mRNA level in HNSCC cell line. Inhibition of the RhoA/ROCK pathway by siRNAs significantly stimulated BRAK gene expression. These results show that the tumor-suppressive effect of Fasudil was mediated by BRAK, suggesting that Fasudil may therefore be useful for the treatment of HNSCC.
CXCL14/BRAK（BRAK）是一种具有抗肿瘤活性的分泌型趋化因子，其在肿瘤细胞中的表达受到抑制。我们之前报道了BRAK在头颈部鳞状细胞癌（HNSCC）细胞系中的抗肿瘤活性以及这些细胞中BRAK分泌的抑制情况。法舒地尔（一种Rho激酶（ROCK）抑制剂）可恢复纤维肉瘤细胞中BRAK的分泌。在本研究中，我们通过评估BRAK在HNSCC细胞系中的基因表达和蛋白分泌来检测其抗肿瘤作用。我们发现BRAK介导了法舒地尔对HNSCC细胞的抑制作用。法舒地尔抑制了雌性BALB/cAJclnu/nu小鼠的肿瘤发展。此外，法舒地尔处理显著刺激了体外肿瘤细胞系中BRAK蛋白的分泌。同样，向培养的肿瘤细胞中添加法舒地尔可显著增加BRAK蛋白的产生。此外，法舒地尔在HNSCC细胞系中显著增加了BRAK基因在mRNA水平的表达。通过小干扰RNA（siRNAs）抑制RhoA/ROCK途径可显著刺激BRAK基因表达。这些结果表明法舒地尔的肿瘤抑制作用是由BRAK介导的，这表明法舒地尔可能因此对HNSCC的治疗有用。
