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1.  Hyperthermia using magnetite cationic liposomes for hamster osteosarcoma 
We have developed magnetite cationic liposomes (MCLs) and applied them to local hyperthermia as a mediator. MCLs have a positive charge and generate heat under an alternating magnetic field (AMF) by hysteresis loss. In this study, the effect of hyperthermia using MCLs was examined in an in vivo study of hamster osteosarcoma.
MCLs were injected into the osteosarcoma and then subjected to an AMF.
The tumor was heated at over 42°C, but other normal tissues were not heated as much. Complete regression was observed in 100% of the treated group hamsters, whereas no regression was observed in the control group hamsters. At day 12, the average tumor volume of the treated hamsters was about 1/1000 of that of the control hamsters. In the treated hamsters, no regrowth of osteosarcomas was observed over a period of 3 months after the complete regression.
These results suggest that this treatment is effective for osteosarcoma.
PMCID: PMC400754  PMID: 15040804
2.  Heat induction of reporter gene expression via the gadd153 promoter and its possible application to hyperthermia treatment of cancer 
Cytotechnology  2000;33(1-3):131-137.
The use of the gadd153promoter to induce expression of a reporter geneunder heat stress conditions was investigated,since the results of previous studies have suggestedthat the gadd153promoter is likely to be activated by the indirecteffects of hyperthermia, that is, by DNA damage thatoccurs when reactive oxygen species are produced byheat stress. The optimum temperature for a significantinduction was found to be between 41 and 43 °C andincreased expression of the reporter gene was observedat about 24 h after the heat treatment. Under theseconditions, the cell integrity was not alteredmorphologically and the growth stopped temporarily,while the viability was maintained. A second increasein expression occurred at a later stage when the cellswere severely damaged at 43–45 °C. Atthese temperatures, the cellular morphology showedsignificant alteration and the growth was stronglyarrested. This is likely to be due to a differentmechanism which could involve DNA repair processes. Itis expected that this method of induction can beexploited to drive the production of a protein ofinterest in a cancer treatment program that includes hyperthermia.
PMCID: PMC3466714  PMID: 19002820
3.  Enhancement of cytokine expression in transiently transfected cells by magnetoliposome mediated hyperthermia 
Cytotechnology  1997;25(1-3):231-234.
We investigated the enhancement of cytokine expression by heat treatment in transiently transfected glioma cells. The cells were transfected with plasmid bearing the interferon (IFN)-β gene under control of the MMTV promoter, which is inducible by glucocorticoid (dexamethasone). Then magnetite particles (10 nm diameter) as intracellular heating material were incorporated to the cells as the form of magnetoliposome. After 5 hours of incorporation, alternative magnetic field (384Oe, 118kHz) was applied for intracellular heating. IFN-β secreted in the medium was assayed and its concentration was compared to the extracellular heating induced expression, both in the presence and absence of dexamethasone. Higher IFN-β concentration was detected in intracellular heating even at lower temperature, 39 °C, than 43 °C in extracellular heating. The IFN-β expression level reached in the presence of dexamethasone was about three times higher than in the absence of inducer. In intracellular heating of 60 min, the surviving cell number reduced until 20%.
PMCID: PMC3466751  PMID: 22358897
heat shock inducible promoter; hyperthermia; interferon-β; magnetoliposome

Results 1-3 (3)