Apoptosis, energy metabolism, and fraction of radiobiologically hypoxic cells: a study of human melanoma multicellular spheroids.

摘要: The magnitude of the fraction radiobiologically hypoxic cells in tumours is generally believed to reflect efficiency vascular network. Theoretical studies have suggested that might also be influenced by biological properties tumour cells. Quantitative experimental results cell energy metabolism, hypoxia- induced apoptosis, and radiobiological hypoxia are reported here. Human melanoma multicellular spheroids (BEX-c WIX-c) were used as models avoid confounding effects Radiobiological showed fractions 1000-microM 32 +/- 12% (BEX-c) 2.5 1.1% (WIX-c). spheroid volume (28 6% 1.4 7% (WIX-c)), calculated from rate oxygen consumption per cell, packing density, thickness viable rim, similar Large differences between therefore not necessarily a result Studies monolayer cultures, performed identify BEX-c WIX-c leading this large difference cells, gave following results: (1) lower surviving after exposure than BEX-c, (2) higher glucose uptake lactate release rates both under aerobic conditions, (3) apoptosis but BEX-c. These observations resulted partly metabolism capacity retain viability stress. induction was identified phenomenon which has an important influence on spheroids.