Effect of heat-drug sequences on thermoenhancement and uptake of cis-DDP in human pharyngeal carcinoma.
To discover the point of maximum interactive effect, we examined the time sequence of high (above (42.5 degrees C) or low (below 42.5 degrees C) -hyperthermia and cis-diammine dichloroplatinum (II) (CDDP). Simultaneous or post-hyperthermic CDDP (0.5 micrograms/ml) treatment at 43 degrees C resulted in a slight synergistic effect, with thermoenhancement ratios (TER) of 1.42 or 1.38, respectively, and there was a significant increase CDDP uptake after both combinations compared with pre-hyperthermic CDDP treatment. However, at 42 degrees C, the maximal interaction (TER = 8.57) was obtained when KB cells were simultaneously heated with CDDP, there was also a significant increase of CDDP uptake by simultaneous procedures compared with pre or post-hyperthermic CDDP treatment. These results indicate that simultaneous or post-hyperthermic CDDP treatment for high-hyperthermia and simultaneous CDDP treatment for low-hyperthermia are the most effective means of CDDP thermochemotherapy with hyperthermia.
Ohtsubo
T
T
Department of Otolaryngology, Fukui Medical School, Japan.
Saito
H
H
Tanaka
N
N
Noda
I
I
Saito
T
T
Kano
E
E
D000970:Antineoplastic Agents / Q000493:pharmacokinetics / Q000494:pharmacology*; D016923:Cell Death / Q000187:drug effects / Q000502:physiology; D002945:Cisplatin / Q000493:pharmacokinetics / Q000494:pharmacology*; D003131:Combined Modality Therapy; D006801:Humans; D006979:Hyperthermia, Induced; D007624:KB Cells; D013696:Temperature
D000970:Antineoplastic Agents; D002945:Cisplatin