title: Increase in cell motility by carbon ion irradiation via the Rho signaling pathway and its inhibition by the ROCK inhibitor Y-27632 in lung adenocarcinoma A549 cells.
abstract: This study aimed to investigate the effect of carbon ion (C-ion) irradiation on cell motility through the ras homolog gene family member (Rho) signaling pathway in the human lung adenocarcinoma cell line A549. Cell motility was assessed by a wound-healing assay, and the formation of cell protrusions was evaluated by F-actin staining. Cell viability was examined by the WST-1 assay. The expression of myosin light chain 2 (MLC2) and the phosphorylation of MLC2 at Ser19 (P-MLC2-S19) were analyzed by Western blot. At 48 h after irradiation, the wound-healing assay demonstrated that migration was significantly greater in cells irradiated with C-ion (2 or 8 Gy) than in unirradiated cells. Similarly, F-actin staining showed that the formation of protrusions was significantly increased in cells irradiated with C-ion (2 or 8 Gy) compared with unirradiated cells. The observed increase in cell motility due to C-ion irradiation was similar to that observed due to X-ray irradiation. Western-blot analysis showed that C-ion irradiation (8 Gy) increased P-MLC2-S19 expression compared with in unirradiated controls, while total MLC2 expression was unchanged. Exposure to a non-toxic concentration of Y-27632, a specific inhibitor of Rho-associated coiled-coil-forming protein kinase (ROCK), reduced the expression of P-MLC2-S19 after C-ion irradiation (8 Gy), resulting in a significant reduction in migration. These data suggest that C-ion irradiation increases cell motility in A549 cells via the Rho signaling pathway and that ROCK inhibition reduces that effect.
authors.affiliation: Department of Radiation Oncology, Gunma University Graduate School of Medicine, 3-39-22, Showa-machi, Maebashi, Gunma 371-8511, Japan.
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Murata
authors.affiliation: Department of Radiation Oncology, Gunma University Graduate School of Medicine, 3-39-22, Showa-machi, Maebashi, Gunma 371-8511, Japan snoda@gunma-u.ac.jp.
authors.forename: Shin-ei
authors.initials: SE
authors.lastname: Noda
authors.affiliation: Department of Radiation Oncology, Gunma University Graduate School of Medicine, 3-39-22, Showa-machi, Maebashi, Gunma 371-8511, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Oike
authors.affiliation: Advanced Scientific Research Leaders Development Unit, Gunma University, 3-39-22, Showa-machi, Maebashi, Gunma 371-8511, Japan.
authors.forename: Akihisa
authors.initials: A
authors.lastname: Takahashi
authors.affiliation: Gunma University Heavy Ion Medical Center, 3-39-22, Showa-machi, Maebashi, Gunma 371-8511, Japan.
authors.forename: Yukari
authors.initials: Y
authors.lastname: Yoshida
authors.affiliation: Department of Radiation Oncology, Gunma University Graduate School of Medicine, 3-39-22, Showa-machi, Maebashi, Gunma 371-8511, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Suzuki
authors.affiliation: Gunma University Heavy Ion Medical Center, 3-39-22, Showa-machi, Maebashi, Gunma 371-8511, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Ohno
authors.affiliation: Microbeam Radiation Biology Group, Japan Atomic Energy Agency, Watanuki 1233, Takasaki, Gunma 370-1292, Japan.
authors.forename: Tomoo
authors.initials: T
authors.lastname: Funayama
authors.affiliation: Microbeam Radiation Biology Group, Japan Atomic Energy Agency, Watanuki 1233, Takasaki, Gunma 370-1292, Japan.
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Kobayashi
authors.affiliation: Department of Radiation Oncology, Saitama Medical Center, Saitama Medical University, 1981, Kamoda, Kawagoe, Saitama 350-8550, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Takahashi
authors.affiliation: Department of Radiation Oncology, Gunma University Graduate School of Medicine, 3-39-22, Showa-machi, Maebashi, Gunma 371-8511, Japan Gunma University Heavy Ion Medical Center, 3-39-22, Showa-machi, Maebashi, Gunma 371-8511, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakano
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D000077192:Adenocarcinoma of Lung; D000577:Amides / Q000494:pharmacology; D024722:Cardiac Myosins / Q000378:metabolism; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000502:physiology / Q000528:radiation effects*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D063193:Heavy Ion Radiotherapy / Q000009:adverse effects*; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D018994:Myosin Light Chains / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology; D015398:Signal Transduction / Q000528:radiation effects; D020741:rho GTP-Binding Proteins / Q000378:metabolism; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000577:Amides; D004791:Enzyme Inhibitors; D018994:Myosin Light Chains; D011725:Pyridines; C107184:myosin light chain 2; C108830:Y 27632; D054460:rho-Associated Kinases; D024722:Cardiac Myosins; D020741:rho GTP-Binding Proteins
keywords: Rho-associated coiled-coil-forming protein kinase (ROCK); carbon ion (C-ion) irradiation; cell motility; non-small cell lung carcinoma (NSCLC); ras homolog gene family member (Rho)