[Investigation on the migration and biologic effects of nano FeOx powders under the exposure of extremely low frequency altering electric magnetic field in human heptoma-bearing nude mice in vivo].

Zhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology · 2011 · Benefit · Low evidence

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Study snapshot

PublicationZhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology · 2011

Study typeanimal

Reported directionBenefit

Evidence ratingLow

Abstract

To investigate the mechanism and biologic effects of 37 nm magnetic nano FeOx powders (MNPs) on human hepatoma-bearing nude mice. 37 nm MNPs were prepared by coprecipitation methods and then injected into human hepatoma (Bel-7402) bearing-nude mice through the tail vein. After injection of MNPs, the mice were first exposed under static magnetic field and then treated under extremely low frequency altering-electric magnetic field directing to the tumor area. The migration and trafficking of MNPs were determined by MMR. Tumor growth was monitored with calipers every 5 days and tumor volume was calculated on the basis of three-dimensioned measurements. The apoptosis of tumor cells was analyzed by flow cytometry analysis. The expressions of apoptosis-associated proteins Bcl-2, Bax and HSP27 were determined using western-blot analysis. Static magnetic field could direct the migration and trafficking of MNPs to the tumor site with a higher ratio of 98.9%. Extremely Low Frequency Electric-Magnetic Field (EMF) treatment could inhibit the proliferation of tumor cells and prolong the survive time of tumor-bearing mice injected with MNPs. In addition, the survival time of tumor-bearing mice and percentages of prohibition on tumor cell growth were 27.4+/-0.7 days and 37.5+/-0.8% (F = 0.005, P is less than to 0.05), respectively. The results of flow cytometry analyses showed that about 18.1+/-0.6% (F = 0.030, P is less than to 0.05) of tumor cells were induced into early apoptosis. Furthermore, expressions of apoptosis-associated proteins Bcl-2 and Bax were significantly induced by MNPs under EMF treatment. The ratio of Bcl/Bax in both MNPs and EMF treatment group was 0.07+/-0.01, which was much lower than that of control group (0.23+/-0.02) (F = 0.016, P is less than to 0.05). Heat shock protein-27 (Hsp-27) was not significantly induced in different treatment groups. Injection of MNPs with EMF exposure on human hepatoma-bearing nude mice could significantly prolong the survival time, inhibit the tumor proliferation and growth, and induce tumor cells into apoptosis.

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Structured fields below were generated from the paper’s abstract and metadata to make the evidence easier to inspect. Automated extraction may be incomplete or incorrect; verify important details against the original paper.

Study typeanimal

Effect directionbenefit

PopulationHuman hepatoma (Bel-7402) bearing nude mice

Sample sizeNot supplied

ExposureELF

Evidence strengthLowConfidence: 74% · Peer reviewed: yes

Main findings

Static magnetic field directed migration/trafficking of 37 nm magnetic nano FeOx powders to the tumor site with a reported ratio of 98.9%. Subsequent extremely low frequency altering electric-magnetic field treatment (with MNP injection) was associated with inhibited tumor cell proliferation, prolonged survival time (27.4±0.7 days), increased early apoptosis (~18.1±0.6%), and altered Bcl-2/Bax (lower Bcl/Bax ratio vs control), while Hsp-27 was not significantly induced.

Outcomes measured

Migration/trafficking of magnetic nano FeOx powders (MNPs) to tumor site
Tumor growth/volume
Survival time
Tumor cell proliferation inhibition
Tumor cell apoptosis (early apoptosis by flow cytometry)
Expression of apoptosis-associated proteins (Bcl-2, Bax)
Expression of HSP27

Limitations

No sample size reported in abstract
Exposure parameters (ELF frequency, field strength, duration) not reported in abstract
Intervention includes both nanoparticle injection and magnetic/EMF exposure; effects of EMF alone cannot be separated from MNPs and static magnetic field
Animal tumor model; generalizability to humans is uncertain

View raw extracted JSON

{
  "study_type": "animal",
  "exposure": {
    "band": "ELF",
    "source": "other",
    "frequency_mhz": null,
    "sar_wkg": null,
    "duration": null
  },
  "population": "Human hepatoma (Bel-7402) bearing nude mice",
  "sample_size": null,
  "outcomes": [
    "Migration/trafficking of magnetic nano FeOx powders (MNPs) to tumor site",
    "Tumor growth/volume",
    "Survival time",
    "Tumor cell proliferation inhibition",
    "Tumor cell apoptosis (early apoptosis by flow cytometry)",
    "Expression of apoptosis-associated proteins (Bcl-2, Bax)",
    "Expression of HSP27"
  ],
  "main_findings": "Static magnetic field directed migration/trafficking of 37 nm magnetic nano FeOx powders to the tumor site with a reported ratio of 98.9%. Subsequent extremely low frequency altering electric-magnetic field treatment (with MNP injection) was associated with inhibited tumor cell proliferation, prolonged survival time (27.4±0.7 days), increased early apoptosis (~18.1±0.6%), and altered Bcl-2/Bax (lower Bcl/Bax ratio vs control), while Hsp-27 was not significantly induced.",
  "effect_direction": "benefit",
  "limitations": [
    "No sample size reported in abstract",
    "Exposure parameters (ELF frequency, field strength, duration) not reported in abstract",
    "Intervention includes both nanoparticle injection and magnetic/EMF exposure; effects of EMF alone cannot be separated from MNPs and static magnetic field",
    "Animal tumor model; generalizability to humans is uncertain"
  ],
  "evidence_strength": "low",
  "confidence": 0.74,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "extremely low frequency",
    "electric-magnetic field",
    "static magnetic field",
    "magnetic nanoparticles",
    "FeOx",
    "nude mice",
    "hepatoma",
    "Bel-7402",
    "apoptosis",
    "Bcl-2",
    "Bax",
    "HSP27",
    "tumor growth",
    "survival"
  ],
  "suggested_hubs": [
    {
      "slug": "occupational-exposure",
      "weight": 0.05,
      "reason": "Mentions extremely low frequency EMF exposure, but context is experimental tumor treatment rather than occupational settings."
    }
  ]
}

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AI-extracted fields are generated from the abstract and metadata and may be incomplete or incorrect. This material is for informational purposes and is not medical advice.

Identifiers and source

DOI: 10.3760/cma.j.issn.1007-3418.2011.08.009
PubMed: 22152316

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