Effects of hyperthermochemoradiotherapy on KSE-1 cells, a newly established human squamous cell line derived from esophageal carcinoma.
Hyperthermia alone inhibits growth of the human esophageal cancer cell line (KSE-1). Even temporary exposure to hyperthermia results in substantial decreases in growth in a time- and temperature-dependent manner. A precipitous decrease in growth occurred at a temperature of approximately 42.5 degrees C. Concomitant application of hyperthermia, bleomycin and irradiation (hyperthermochemoradiotherapy, HCR) had a maximal effect on cell growth, compared to findings in cells treated with only one or two of these modalities. Fractionated hyperthermia (42 degrees C, 60 min) at a time interval of under 12 h was less effective than a single application (42 degrees C, 120 min). However, over a 12-hour time interval, the effects of both treatments were similar. Fractionated HCR (hyperthermia: 42 degrees C, 60 min; chemotherapy: 2 micrograms/ml of bleomycin, 60 min; radiotherapy: 2 Gy) at a time interval of under 21 h was less effective than a single HCR (hyperthermia: 42 degrees C, 120 min; chemotherapy: 2 micrograms/ml of bleomycin, 120 min; radiotherapy: 4 Gy). We conclude that care should be taken regarding development of thermotolerance when combined modality therapy is given.
Matsuoka
H
H
Department of Surgery II, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Sugimachi
K
K
Mori
M
M
Kuwano
H
H
Ohno
S
S
Nakano
S
S
D000818:Animals; D001761:Bleomycin / Q000494:pharmacology; D002455:Cell Division; D003131:Combined Modality Therapy; D006224:Cricetinae; D004938:Esophageal Neoplasms / Q000473:pathology*; D005260:Female; D006358:Hot Temperature; D006801:Humans; D011879:Radiotherapy Dosage; D014407:Tumor Cells, Cultured; D014410:Tumor Stem Cell Assay; D014965:X-Rays
D001761:Bleomycin