An upward 9.4 T static magnetic field inhibits DNA synthesis and increases ROS-P53 to suppress lung cancer growth

a b s t r a c tStudies have shown that 9.4 Tesla (9.4 T) high-field magnetic resonance imaging (MRI) has obvious advantages inimproving image resolution and capacity, but their safety issues need to be further validated before their clinicalapproval. Meanwhile, emerging experimental evidences show that moderate to high intensity Static MagneticFields (SMFs) have some anti-cancer effects.We examined the effects of two opposite SMF directions on lung cancer bearing mice and found when the lungcancer cell-bearing mice were treated with 9.4 T SMFs for 88 h in total, the upward 9.4 T SMF significantlyinhibited A549 tumor growth (tumor growth inhibition=41%), but not the downward 9.4 T SMF. In vitro cellularanalysis shows that 9.4 T upward SMF treatment for 24 h not only inhibited A549 DNA synthesis, but alsosignificantly increased ROS and P53 levels, and arrested G2 cell cycle. Moreover, the 9.4 T SMF-treatments for88 h had no severe impairment to the key organs or blood cell count of the mice.Our findings demonstrated the safety of 9.4 T SMF long-term exposure for their future applications in MRI, andrevealed the anti-cancer potential of the upward direction 9.4 T SMF.

摘要：研究表明，9.4特斯拉（9.4 T）高场磁共振成像（Magnetic Resonance Imaging，MRI）在提升图像分辨率与成像容量方面具备显著优势，但其安全性仍需在临床应用前得到进一步验证。与此同时，新兴实验证据显示，中高强度静磁场（Static Magnetic Fields，SMFs）具备一定的抗癌功效。本研究考察了两种相反方向的静磁场对荷瘤小鼠的影响，结果发现，当接种肺癌细胞的小鼠累计接受9.4 T静磁场处理88小时后，正向9.4 T静磁场可显著抑制A549肿瘤生长（肿瘤生长抑制率=41%），而反向9.4 T静磁场则无此效果。体外细胞实验分析显示，接受24小时正向9.4 T静磁场处理后，A549细胞的DNA合成不仅受到抑制，活性氧（Reactive Oxygen Species，ROS）与P53蛋白水平亦显著升高，且细胞周期出现G2期阻滞。此外，累计接受88小时9.4 T静磁场处理并未对小鼠的关键脏器或血细胞计数造成严重损伤。本研究结果证实了长期暴露于9.4 T静磁场的安全性，为其未来在磁共振成像中的应用提供了支撑，并揭示了正向9.4 T静磁场的抗癌潜力。