PT  - JOURNAL ARTICLE
AU  - Li Chen
AU  - Jianmin Wang
AU  - Xiaoping Xu
AU  - Lei Gao
AU  - Xinhong Fei
AU  - Jingwei Lou
AU  - Zhengxia Huang
TI  - The Synergistic Inhibitory Effect of STI571 in Combination with Arsenic Trioxide (AS<sub>2</sub>O<sub>3</sub>) on Multidrug-Resistant Leukemic Cells
DP  - 2005 Jun 01
TA  - Chinese Journal of Clinical Oncology
PG  - 671--674
VI  - 2
IP  - 3
4099  - http://www.cancerbiomed.org/content/2/3/671.short
4100  - http://www.cancerbiomed.org/content/2/3/671.full
SO  - Cancer Biol Med2005 Jun 01; 2
AB  - OBJECTIVE To study the synergistic effect of STI571, an inhibitor of tyrosine kinase, in combination with arsenic trioxide As2O3 on a multidrug-resistant leukemia cell line expressing bcr-abl.METHODS The cytotoxic effect of STI571 alone or in combination with different concentrations of As2O3 on the bcr-abl and mdr1-positive leukemia cell line, K562-n/VCR, was examined by the MTT method.RESULTS One μmol/L of STI571 alone had no significant cytotoxic effect on K562-n/VCR cells. However the cytotoxic effect increased markedly when combined with As2O3 at concentrations of 10-5, 10-6, 10-7 and 10-8 mol/L. The IC50 of K562-n/VCR cells in As2O3 group was 1.879 mol/L, with Upon addition of STI571, the IC50 decreased to 0.155 μmol/L resulting in a synergistic cytotoxic effect on K562-n/VCR cells that was increased 12.1 times.CONCLUSION A combination of STI571 with As2O3 has a more powerful inhibitory effect on leukemia cells expressing positive bcr-abl and positive mdrl compared to the effect with As2O3 alone.