THERMAL ENHANCEMENT OF TETRAPLATIN AND CARBOPLATIN IN HUMAN LEUKEMIC-CELLS

The thermal enhancement of tetraplatin (racemic, d-trans and l-trans isomers) and carboplatin was studied as a function of temperature in vitro in JM, a human acute lymphoblastic leukaemia cell line. Exponentially growing JM cells were exposed to tetraplatin (0-10 μg/ml) or carboplatin (0-45 μg/ml) for 1 h at 37-43°C in 1°C increments. Graphic analysis demonstrated a breakpoint for the onset of thermal enhancement for tetraplatin at 40°C. Thermal enhancement was maximal at 42°C with no significant increase at 43°C. The tetraplatin thermal enhancement ratio (TER) was 2.7 at 42°C. The TERs for d and / isomers at 41.8°C were not significantly different. The relationship of TER to temperature for carboplatin closely paralleled that of tetraplatin. The implications of these results are discussed in the context of tetraplatin's unique properties. © 1990 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.