Martínez María Antonia, Úbeda Alejandro, Trillo María Àngeles
Serv. Investigación-BEM, Hosp. Universitario Ramón y Cajal-IRYCIS, Madrid, Spain,
Serv. Investigación-BEM, Hosp. Universitario Ramón y Cajal-IRYCIS, Madrid, Spain.
Cell Physiol Biochem. 2019;52(4):893-907. doi: 10.33594/000000062.
BACKGROUND/AIMS: Previous studies have shown that a 63-hour, intermittent exposure to a 50 Hz, 100 μT magnetic field (MF) induces in the NB69 line of human neuroblastoma a proliferative response that is mediated by activation of the MAPK pathways ERK1/2 and p38. The present study aims to investigate the potential involvement of the epidermal growth factor receptor (EGFR) in the field-induced cell proliferation and activation of MAPK pathways.
NB69 cultures were MF- or sham-exposed for 5 to 30 minute intervals and 63 hours. Cell proliferation and activation of MAPK-ERK1/2, -p38 and -JNK was analyzed in the presence or absence of erlotinib, an effective inhibitor of EGFR tyrosine kinase. The expression of p-EGFR and MMP-9 in the presence or absence of MF was also studied. Between 3 and 7 replicates of each experiment were performed, using between 3 and 4 samples per experimental condition and replicate. At the end of each replicate, the samples were analyzed at short times (5-30 min) through immunofluorescence and Western blotting, and the growth response was assessed (63 hours interval) through dye exclusion with Trypan blue.
The results confirmed that field exposure induces cell proliferation and activation of ERK1/2, p38 and JNK, and revealed that these effects were blocked with erlotinib. The data also showed that, compared to shamexposed controls, the MF exposure induces early and transient increases in the expression of p-EGFR and MMP-9 at 15 and 5 min from the exposure onset, respectively.
The obtained results reveal that the activation of the MAPK-ERK1/2 and -p38 pathways by the MF is mediated by the EGF receptor. Taken together with our previously published results, this dataset suggests that the proliferative response induced in NB69 by a 63-hour exposure to a weak, power frequency MF, is mediated by early transient activation of EGFR in which MMP-9 would be involved.
背景/目的：先前的研究表明，63小时间歇性暴露于50Hz、100μT的磁场（MF）可诱导人神经母细胞瘤NB69细胞系产生增殖反应，该反应由丝裂原活化蛋白激酶（MAPK）途径ERK1/2和p38的激活介导。本研究旨在探讨表皮生长因子受体（EGFR）在磁场诱导的细胞增殖及MAPK途径激活中的潜在作用。
将NB69细胞培养物分别进行MF暴露或假暴露，暴露时间间隔为5至30分钟，共63小时。在存在或不存在埃罗替尼（一种有效的EGFR酪氨酸激酶抑制剂）的情况下，分析细胞增殖以及MAPK-ERK1/2、-p38和-JNK的激活情况。还研究了在存在或不存在MF的情况下p-EGFR和基质金属蛋白酶-9（MMP-9）的表达。每个实验进行3至7次重复，每个实验条件和重复使用3至4个样本。在每次重复结束时，通过免疫荧光和蛋白质印迹在短时间（5 - 30分钟）分析样本，并通过台盼蓝染料排除法评估生长反应（63小时间隔）。
结果证实磁场暴露可诱导细胞增殖以及ERK1/2、p38和JNK的激活，并表明这些效应被埃罗替尼阻断。数据还显示，与假暴露对照组相比，MF暴露分别在暴露开始后15分钟和5分钟诱导p-EGFR和MMP-9表达的早期短暂增加。
所得结果表明，MF对MAPK-ERK1/2和-p38途径的激活由EGF受体介导。结合我们之前发表的结果，该数据集表明，63小时暴露于弱工频MF诱导的NB69细胞增殖反应由EGFR的早期短暂激活介导，其中MMP-9可能参与其中。
