Ohnishi Yuichi, Yasui Hiroki, Kakudo Kenji, Nozaki Masami
Department of Cell Biology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan; Second Department of Oral and Maxillofacial Surgery, Osaka Dental University, Hirakata, Osaka 573-1121, Japan.
Second Department of Oral and Maxillofacial Surgery, Osaka Dental University, Hirakata, Osaka 573-1121, Japan.
Oncol Lett. 2017 Feb;13(2):930-936. doi: 10.3892/ol.2016.5500. Epub 2016 Dec 14.
Cell migration potency is essential in cancer metastasis and is often regulated by extracellular stimuli. Oral squamous cell carcinoma cell lines include those that are sensitive, as well as resistant, to the effects of the epidermal growth factor receptor (EGFR) inhibitor cetuximab on cell migration. In the present study, the molecular differences in the EGFR response to cell migration between the SAS cetuximab-sensitive and HSC4 cetuximab-resistant cell lines was examined. Treatment with the EGFR inhibitors AG1478 and cetuximab reduced the migration potency of SAS cells, but not HSC4 cells. The migration of the two cell lines was inhibited under serum-free culture conditions, and the addition of EGF to the serum-free medium promoted the migration of SAS cells, but not HSC4 cells. In addition, SAS cell migration was reduced by the mitogen-activated protein kinase kinase and protein kinase B (Akt) inhibitors PD98059 and MK2206, whereas HSC4 cell migration was only inhibited by MK2206. EGF induced an increase in extracellular signal-regulated kinase phosphorylation levels in HSC4 cells, and stimulated Akt phosphorylation levels in SAS cells. Furthermore, the staining of actin filaments with phalloidin was significantly increased by the inhibition of EGFR in SAS cells, but was not observed as altered in HSC4 cells. Conversely, the addition of EGF to the culture medium decreased the accumulation of actin filaments in SAS cells. The results suggest that the EGF-EGFR signaling pathway has an important role in SAS cell migration via the modulation of actin dynamics, and that HSC4 cell migration is regulated by a serum component other than EGFR.
细胞迁移能力在癌症转移中至关重要，且常常受到细胞外刺激的调控。口腔鳞状细胞癌细胞系包括对表皮生长因子受体（EGFR）抑制剂西妥昔单抗的细胞迁移效应敏感以及耐药的细胞系。在本研究中，检测了SAS西妥昔单抗敏感细胞系和HSC4西妥昔单抗耐药细胞系之间EGFR对细胞迁移反应的分子差异。用EGFR抑制剂AG1478和西妥昔单抗处理可降低SAS细胞的迁移能力，但对HSC4细胞无此作用。在无血清培养条件下，两种细胞系的迁移均受到抑制，向无血清培养基中添加表皮生长因子（EGF）可促进SAS细胞的迁移，但对HSC4细胞无促进作用。此外，丝裂原活化蛋白激酶激酶和蛋白激酶B（Akt）抑制剂PD98059和MK2206可降低SAS细胞的迁移，而HSC4细胞迁移仅被MK2206抑制。EGF可诱导HSC4细胞中细胞外信号调节激酶磷酸化水平升高，并刺激SAS细胞中Akt磷酸化水平升高。此外，在SAS细胞中，用鬼笔环肽对肌动蛋白丝进行染色，EGFR抑制后染色显著增加，但在HSC4细胞中未观察到染色改变。相反，向培养基中添加EGF可减少SAS细胞中肌动蛋白丝的积累。结果表明，EGF-EGFR信号通路通过调节肌动蛋白动力学在SAS细胞迁移中起重要作用，且HSC4细胞迁移受EGFR以外的血清成分调控。
