Lage H, Helmbach H, Dietel M, Schadendorf D
Institute of Pathology, Charité, Humboldt University Berlin, Germany.
Br J Cancer. 2000 Jan;82(2):488-91. doi: 10.1054/bjoc.1999.0947.
The role of DNA topoisomerases (Topo) IIalpha and IIbeta was investigated in various drug-resistant melanoma cells. Melanoma cells resistant to etoposide, exhibited an up to tenfold reduced Topo II activity corresponding to an increasing degree of drug resistance indicating that modulation of Topo II activity contribute to the drug-resistant phenotype. The reduction of Topo II activity was reflected by decreased nuclear amounts of both Topo II isoforms.
在各种耐药性黑色素瘤细胞中研究了DNA拓扑异构酶(Topo)IIα和IIβ的作用。对依托泊苷耐药的黑色素瘤细胞,其Topo II活性降低了多达10倍,这与耐药程度的增加相对应,表明Topo II活性的调节促成了耐药表型。Topo II活性的降低表现为两种Topo II亚型的核含量减少。