The response of human and rodent cells to hyperthermia.

Inherent cellular radiosensitivity in vitro has been shown to be a good predictor of human tumor response in vivo. In contrast, the importance of the intrinsic thermosensitivity of normal and neoplastic human cells as a factor in the responsiveness of human tumors to adjuvant hyperthermia has never been analyzed systematically. A comparison of thermal sensitivity and thermo-radiosensitization in four rodent and eight human-derived cell lines was made in vitro. Arrhenius plots indicated that the rodent cells were more sensitive to heat killing than the human, and the break-point was 0.5 degrees C higher for the human than rodent cells. The relationship between thermal sensitivity and the interaction of heat with X rays at low doses was documented by thermal enhancement ratios (TER's). Cells received either a 1 hr exposure to 43 degrees C or a 20 minute treatment at 45 degrees C before exposure to 300 kVp X rays. Thermal enhancement ratios ranged from 1.0 to 2.7 for human cells heated at 43 degrees C and from 2.1 to 5.3 for heat exposures at 45 degrees C. Thermal enhancement ratios for rodent cells were generally 2 to 3 times higher than for human cells, because of the fact that the greater thermosensitivity of rodent cells results in a greater enhancement of radiation damage. Intrinsic thermosensitivity of human cells has relevance to the concept of thermal dose; intrinsic thermo-radiosensitization of a range of different tumor cells is useful in documenting the interactive effects of radiation combined with heat.

[1]  J. Pirro,et al.  A comparison of the heat and radiation sensitivity of rodent and human derived cells cultured in vitro. , 1986, International Journal of Radiation Oncology, Biology, Physics.

[2]  J. Overgaard,et al.  Some problems related to the clinical use of thermal isoeffect doses. , 1987, International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group.

[3]  E. Hall,et al.  Biological effects of heat. , 1984, Cancer research.

[4]  J. Overgaard,et al.  Hyperthermia as an adjuvant to radiotherapy in the treatment of malignant melanoma. , 1987, International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group.

[5]  B. Fertil,et al.  Distribution of radiation sensitivities for human tumor cells of specific histological types: comparison of in vitro to in vivo data. , 1986, International journal of radiation oncology, biology, physics.

[6]  Time-temperature relationships for hyperthermal radiosensitisation in mouse intestine: influence of thermotolerance. , 1985, Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology.

[7]  The concept of thermal dose. , 1988, Recent results in cancer research. Fortschritte der Krebsforschung. Progres dans les recherches sur le cancer.

[8]  P Rous,et al.  Recent Advances in Cancer Research. , 1947, Bulletin of the New York Academy of Medicine.

[9]  B. Fertil,et al.  Inherent cellular radiosensitivity as a basic concept for human tumor radiotherapy. , 1981, International journal of radiation oncology, biology, physics.

[10]  K. Henle,et al.  TIME‐TEMPERATURE RELATIONSHIPS FOR HEAT‐INDUCED KILLING OF MAMMALIAN CELLS * , 1980, Annals of the New York Academy of Sciences.

[11]  W. Dewey,et al.  Intrinsic differences in heat and/or X-ray sensitivity of seven mammalian cell lines cultured and treated under identical conditions. , 1979, Cancer research.

[12]  W A Brock,et al.  Initial slope of radiation survival curves is characteristic of the origin of primary and established cultures of human tumor cells and fibroblasts. , 1987, Radiation research.

[13]  Peter Armitage,et al.  THE DESIGN OF CLINICAL TRIALS , 1979 .

[14]  J. Pirro,et al.  Thermotolerance in human cells of normal and neoplastic origin. , 1988, International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group.

[15]  W. Dewey,et al.  Cellular responses to combinations of hyperthermia and radiation. , 1977, Radiology.

[16]  C. Perez,et al.  Combination of surgery, irradiation, and hyperthermia in treatment of recurrences of malignant tumors. , 1987, International journal of radiation oncology, biology, physics.

[17]  G. Hahn.  Hyperthermia and Cancer , 1982, Springer US.

[18]  S. B. Field,et al.  The problem of defining thermal dose. , 1988, Recent results in cancer research. Fortschritte der Krebsforschung. Progres dans les recherches sur le cancer.

[19]  C. Perez,et al.  Irradiation alone or combined with hyperthermia in the treatment of recurrent carcinoma of the breast in the chest wall: a nonrandomized comparison. , 1986, International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group.

[20]  S. B. Field,et al.  The relationship between heating time and temperature: its relevance to clinical hyperthermia. , 1983, Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology.

[21]  C. Streffer,et al.  The biological basis for tumour therapy by hyperthermia and radiation. , 1987, Recent results in cancer research. Fortschritte der Krebsforschung. Progres dans les recherches sur le cancer.

[22]  E. Dikomey.  Differential cytotoxic effects on hyperthermia below and above 43 degree C alone or combined with X irradiation. , 1981, Radiation research.

[23]  L. Peters,et al.  Potential methods for predicting tumor radiocurability. , 1986, International journal of radiation oncology, biology, physics.