Physicochemical and immunologic properties of 6-aminolevulinate (ALA) dehydratase in human K562 erythroleukemia cells were examined. ALA dehydratase activity was found to increase in K562 cells after treatment with butyric acid or selenium oxide. Enzyme activity in untreated K562 cells was comparable to that in normal adult erythrocytes but was increased threeto six-fold in K562 cells treated w...

A series of novel podophyllotoxin derivatives were designed and synthesized. The cytotoxic activities of these compounds were tested against three tumor cell lines (HeLa, K562, and K562/A02). Most of the derivatives (IC50 = 1-20 μM) were found to have stronger cell growth inhibitory activity than positive control etoposide. Among them, 4β-N-[(E)-(5-((4-(4-nitrophenyl)-piperazin-1-yl)methyl)fura...

Activin A, a member of the transforming growth factor (TGF)-beta superfamily, is involved in the regulation of erythroid differentiation. Previous studies have shown that activin A inhibited the colony-forming activity of mouse Friend erythroleukemia cells, however, the mechanism remains unknown. First, we show herein that activin A induced the expression and activated the promoters of alpha-gl...

BACKGROUND Several studies have shown that multidrug transporters, such as P-glycoprotein (PGP), are involved in cell resistance to chemotherapy and refractory epilepsy. The p38 mitogen-activated protein kinase (MAPK) signaling pathway may increase PGP activity. However, p38-mediated drug resistance associated with PGP is unclear. Here, we investigated p38-mediated doxorubicin-induced drug resi...

BACKGROUND Chronic myelogenous leukemia (CML) has unsatisfactory treatment efficacy at present. As the major component of red orpiment, tetra-arsenic tetra-sulfide (As4S4) has been recently used in treating leukemia, but with unclear mechanism targeting CML. MicroRNA (miR) is a group of endogenous non-coding RNAs regulating pathogenesis. MiR181 has been shown to exert important roles in tumor p...