Variation in heat sensitivity through the cell cycle of M10 and Burkitt P3HR-1 cells.
The cell-cycle age response to 44 or 45 degrees C hyperthermic treatment was studied in M10, a mutant of mouse L5178Y cells, and human Burkitt P3HR-1 cells synchronized by centrifugal elutriation. Survival response to 44 degrees C hyperthermia or radiation showed that Burkitt cells were relatively hyperthermic resistant and average in radiosensitivity, while M10 cells were relatively hyperthermic sensitive and substantially radiosensitive. A typical age-response to hyperthermia through the cell-cycle was observed in M10 cells, although no significant variation in the response to hyperthermia was demonstrated in Burkitt P3HR-1 cells. Combined effect of procaine with 44 degrees C 20-min treatment for Burkitt P3HR-1 cells showed a substantial enhancement of cytotoxicity in S phase cells. The probable implication of membrane composition, membrane changes due to heat and its modifying agents are discussed. Furthermore, when hyperthermia was combined with radiation in Burkitt P3HR-1 cells, cytotoxic enhancement was observed in G1/S boundary phase, not in S phase.
Malyapa
R S
RS
Department of Radiation Biology, Hiroshima University, Japan.
Sawada
S
S
D000818:Animals; D002453:Cell Cycle / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects; D003131:Combined Modality Therapy; D006801:Humans; D006979:Hyperthermia, Induced; D011343:Procaine / Q000494:pharmacology; D011836:Radiation Tolerance; D016196:S Phase; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000473:pathology / Q000528:radiation effects
D011343:Procaine