Low frequency magnetic fields enhance antitumor immune response against mouse H22 hepatocellular carcinoma

PLoS One. 2013 Nov 20;8(11):e72411. doi: 10.1371/journal.pone.0072411. eCollection 2013.

Abstract

Objective: Many studies have shown that magnetic fields (MF) inhibit tumor growth and influence the function of immune system. However, the effect of MF on mechanism of immunological function in tumor-bearing mice is still unclear.

Methods: In this study, tumor-bearing mice were prepared by subcutaneously inoculating Balb/c mice with hepatocarcinoma cell line H22. The mice were then exposed to a low frequency MF (0.4 T, 7.5 Hz) for 30 days. Survival rate, tumor growth and the innate and adaptive immune parameters were measured.

Results: MF treatment could prolong survival time (n = 28, p<0.05) and inhibit tumor growth (n = 9, p<0.01) in tumor-bearing mice. Moreover, this MF suppressed tumor-induced production of cytokines including interleukin-6 (IL-6), granulocyte colony- stimulating factor (G-CSF) and keratinocyte-derived chemokine (KC) (n = 9-10, p<0.05 or 0.01). Furthermore, MF exposure was associated with activation of macrophages and dendritic cells, enhanced profiles of CD4(+) T and CD8(+) T lymphocytes, the balance of Th17/Treg and reduced inhibitory function of Treg cells (n = 9-10, p<0.05 or 0.01) in the mice model.

Conclusion: The inhibitory effect of MF on tumor growth was related to the improvement of immune function in the tumor-bearing mice.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptive Immunity / physiology
  • Animals
  • Carcinoma, Hepatocellular / blood
  • Carcinoma, Hepatocellular / immunology*
  • Carcinoma, Hepatocellular / therapy*
  • Cell Line, Tumor
  • Cell Survival / physiology
  • Cytokines / blood
  • Female
  • Flow Cytometry
  • Immunity, Innate / physiology
  • Immunohistochemistry
  • Liver Neoplasms / blood
  • Liver Neoplasms / immunology*
  • Liver Neoplasms / therapy*
  • Magnetic Fields*
  • Mice
  • Mice, Inbred BALB C
  • Real-Time Polymerase Chain Reaction
  • T-Lymphocytes / immunology

Substances

  • Cytokines

Grants and funding

This work was supported by the National Natural Science Foundation of China (81101552/81070839), the Natural Science Foundation of Jiangsu Province (BK2011571& BK2012744), Specialized Research Fund for the Doctoral Program of Higher Education (20100091120002), the Ministry of Science and Technology “Twelfth Five-Year” national scientific and technological support for major projects (2012BA/15B03), Key Project supported by Medical Science and Technology Development Foundation, Nanjing Department of Health (ZKX10030), and Jiangsu Province’s Outstanding Medical Academic Leader Program (No.LJ201110). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.