1986 Volume 2 Issue 2 Pages 157-163
Experimental mouse leukemia L1210 cells were subjected to hyperthermia (43.0±0.05°C, waterbath) and photodynamic therapy (50μg/ml HpD, 630 ± 5nm at 0.1mW/cm2) for varying lengths of time and sequences. The results show that the two modalities intract in a manner which is more cytotoxic than the sum of the individual treatments, and the sequence of treatments is a determining factor in the degree of interaction of the HpD-uptake by the tumor cells. The most cytotoxic effect of photodynamic therapy is seen when the photodynamic therapy is treated after hyperthermia with HpD. When hyperthermia is done after HpD-uptake and photodynamic therapy, additive cytotoxic effect is obtained by analysis of dose-response curves. These data are supported on DNA damage (amount of single strand DNA) and RNA damage with analysing by flow cytometer to which the treated cells are stained with acridine orange (AO). Furthermore, an application to the clinical treatment, namely, the photodynamic therapy after the hyperthermia with HpD injection was able to propose as an useful combination therapy from the obtained finding in vitro experiments.
