Micronucleus formation in human melanoma xenografts following exposure to hyperthermia

摘要: The formation of micronuclei in two human melanoma xenografts (E. E. and V. N.) following hyperthermic treatment (42.5° C for 60 min) was studied compared to that single dose irradiation. melanomas were grown the hind leg athymic mice heated by immersing tumour-bearing into a water-bath. Histological sections prepared from tumours removed at predetermined times after fraction abnormal mitotic figures number per nucleus scored. During first 24 h treatment, increased abruptly 90%–100% followed rapid decrease 40%–50%. It then decreased slowly towards about twice level untreated tumours. started increase same time as highest, reached maximum 2–3 days slowly. seen lower than radiation treatments causing similar tumour regrowth delays. resulted more larger delays N. melanoma. present results indicate DNA damage is involved heat-induced cell death treated vivo.