We have investigated the molecular basis of the 100-fold resistance of mutant human erythroleukemia K562/PMEA-1 cells to the antiproliferative potential of 9-(2-phosphonylmethoxyethyl)adenine (PMEA). Upon exposure to high PMEA concentrations, comparable intracellular PMEA levels were initially observed in mutant K562/PMEA-1 and wild-type K562/0 cells, indicating that PMEA influx was unaltered. ...

Membrane currents were examined in a drug-sensitive human leukemia cell line (K562) and its multidrug-resistant cell line (K562/ADM) under the whole-cell variation of the patch electrode voltage clamp technique. Most K562 cells showed only the outward current, which was completely suppressed by internal Cs* ions and 20 HIMethyleneglycol bis(0-aminoethyl ctht-r)-.V..V..V. V'-tetraacelkacid. In c...

BACKGROUND Leukemia seriously threatens human life and health. MicroRNAs can regulate cell growth, proliferation, and death. This article investigated the role of miR-29 on regulating leukemia cell growth, proliferation, and apoptosis. MATERIAL AND METHODS miR-29 and scramble miRNA were transfected to K562 cells. MTT assay, colony formation assay, caspase-3 activity detection, and flow cytome...

OBJECTIVE A novel multi-drug resistance gene named as HA117 has been screened and cloned in multidrug resisitant leukemia cell lines in our previous research, but its function is still unknown. In this study, HA117 gene was investigated whether it could increase the drug resistance in chronic myelogenous myeloid leukemia cell line K562. METHODS HA117 was cloned and adenovirus vectors were con...

Background: RNA interference (RNAi) is the mechanism of gene silencing-mediated messenger RNA degradation by small interference RNA (siRNA), which becomes a powerful tool for in vivo research, especially in the areas of cancer. In this research, the potential use of an expression vector as a specific siRNA producing tool for silencing of Bcr-abl in K562 cell line has been investigated. Methods:...

Membrane currents were examined in a drug-sensitive human leukemia cell line (K562) and its multidrug-resistant cell line (K562/ADM) under the whole-cell variation of the patch electrode voltage clamp technique. Most K562 cells showed only the outward current, which was completely suppressed by internal Cs+ ions and 20 mM ethyleneglycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid. In ...

We have investigated the hormonal responsiveness of K562 cells using a serum-substituted in vitro clonogenic assay. Dexamethasone inhibited colony formation by the K562 cells. and the inhibitory effect could be reversed by progesterone (10 M). Fluoxymesterone caused a prominent enhancement of K562 colony growth. whereas estriol had no effect. Stimulation by triiodothyronine was maximal at iO M....