Microwave-induced Apoptosis and Cytotoxicity of NK Cells through ERK1/2 Signaling

• Published in: Biomedical and environmental sciences Vol. 30; no. 5; pp. 323 - 332
• Main Authors: ZHAO, Li, LI, Jing, HAO, Yan Hui, GAO, Ya Bing, WANG, Shui Ming, ZHANG, Jing, DONG, Ji, ZHOU, Hong Mei, LIU, Shu Chen, PENG, Rui Yun
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.05.2017; Department of Experimental Pathology, Beijing Institute of Radiation Medicine, Beijing 100850, China%Department of Pathology, General Hospital of Beijing Command of PLA, Beijing 100700, China
• Subjects: Apoptosis; Apoptosis - radiation effects; Cell cycle; Cell Cycle - radiation effects; Cell Line; Cytotoxicity; Dose-Response Relationship, Radiation; Down-Regulation; Humans; Killer Cells, Natural - radiation effects; MAP Kinase Signaling System; Microwave; Microwaves - adverse effects; Natural killer cells; NK Cell Lectin-Like Receptor Subfamily K - genetics; NK Cell Lectin-Like Receptor Subfamily K - metabolism; Perforin; Signal Transduction; Microwave; Cytotoxicity; Natural killer cells; Perforin; Cell cycle; Apoptosis
• ISSN: 0895-3988; 2214-0190
• DOI: 10.3967/bes2017.043

Objective To investigate microwave-induced morphological and functional injury of natural killer（NK） cells and uncover their mechanisms. Methods NK-92 cells were exposed to 10, 30, and 50 m W/cm~2 microwaves for 5 min. Ultrastructural changes, cellular apoptosis and cell cycle regulation were detected at 1 h and 24 h after exposure. Cytotoxic activity was assayed at 1 h after exposure, while perforin and NKG2 D expression were detected at 1 h, 6 h, and 12 h after exposure. To clarify the mechanisms, phosphorylated ERK（p-ERK） was detected at 1 h after exposure. Moreover, microwave-induced cellular apoptosis and cell cycle regulation were analyzed after blockade of ERK signaling by using U0126. Results Microwave-induced morphological and ultrastructural injury, dose-dependent apoptosis（P 〈 0.001） and cell cycle arrest（P 〈 0.001） were detected at 1 h after microwave exposure. Moreover, significant apoptosis was still detected at 24 h after 50 m W/cm~2 microwave exposure（P 〈 0.01）. In the 30 m W/cm~2 microwave exposure model, microwaves impaired the cytotoxic activity of NK-92 cells at 1 h and down regulated perforin protein both at 1 h and 6 h after exposure（P 〈 0.05）. Furthermore, p-ERK was down regulated at 1 h after exposure（P 〈 0.05）, while ERK blockade significantly promoted microwave-induced apoptosis（P 〈 0.05） and downregulation of perforin（P 〈 0.01）. Conclusion Microwave dose-dependently induced morphological and functional injury in NK-92 cells, possibly through ERK-mediated regulation of apoptosis and perforin expression.