The study aim was to investigate the impacts of K562 cells towards the activities of Toll-like receptor pathway of human mesenchymal stem cell-bone marrow (HMSC-bm). The in vitro co-culture of HMSC-bm and K562 cells was set as the experiment group (HMSC-bm + K562), the HMSC-bm cultured alone was set as the control group (HMSC-bm), the expressions of six interested genes and their proteins, name...

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...

BACKGROUND To identify novel proteins involved in multidrug resistance in chronic myeloid leukemia (CML). MATERIALS AND METHODS Comparative proteomics was used to screen multidrug resistance-related proteins from K562 and K562/A02; the differently expressed proteins were further confirmed by western blot and real-time PCR. short hairpin RNA (shRNA) assay was applied to determine the relations...

Resistance to cytosine arabinoside (Ara-C) is a major problem in the treatment of patients with acute myeloid leukemia (AML). In order to investigate the mechanisms involved in Ara-C resistance, the gene expression profile of Ara-C-resistant K562 human myeloid leukemia cells (K562/AC cells) was compared to that of Ara-C-sensitive K562 cells (K562 cells) by using a cDNA microarray platform. Corr...

BACKGROUND Natural killer (NK) cells constantly survey surrounding tissues and remove newly generated cancer cells, independent of cancer antigen recognition. Although there have been a number of attempts to apply NK cells for cancer therapy, clinical application has been somewhat limited because of the difficulty in preparing a sufficient number of NK cells. Therefore, ex vivo NK cell expansio...

Riccardin F and pakyonol, macrocyclic bisbibenzyls from Plagiochasm intermedium, have been confirmed to possess antifungic activities against Candida albicans. Herein, we evaluated their anti-tumor activity in vitro by employing K562 and K562/A02 cells, the well-known adriamycin (ADR)-induced multidrug resistance (MDR) tumor cell lines over-expressing P-glycoprotein (P-gp). 3-(4,5-dimethylthiaz...

We have previously demonstrated that continuous exposure of human HL-60 human promyelocytes to 1-fl-D-arabinofuranosylcytosine (araC) results in the induction of terminal differentiation to monocyte-like cells. The present study extends these findings by demonstrating that ara-C induces hemoglobin synthesis in human K562 erythroleukemia cells. This effect occurs maximally at an ara-C concentrat...

This study aims to evaluate the multidrug resistance (MDR) reversal activity by magnetic nanoparticles of Fe3O4 (MNPs-Fe3O4) and 5-bromotetrandrine (BrTet) MDR cell line K562/A02 solitarily or symphysially. The proliferation of K562 and K562/A02 cells and the cytotoxicity on peripheral blood mononuclear cells (PMBCs) were evaluated by MTT assay. Cellular accumulation of daunorubicin (DNR) was a...

K562-R, a pleiotropic drug-resistant cell line established in vitro, and K562-S, the chemotherapy-sensitive parent line, were used as targets in the natural killer cell (NK) system. At each of the effectortarget ratios studied, the K562-R demonstrated a decrease in their susceptibility to both unstimulated and interferon-activated NK cells, as compared to the K562-S line. This difference did no...

A subpopulation of low density granular lymphocytes that express the natural killer (NK) cell-associated Leu-11 antigen (IgG Fc receptor) were stimulated directly by coculture with an NK-sensitive tumor cell, K562. T lymphocytes (Leu-11-) responded only weakly when cocultured with K562. The response of Leu-11+ cells apparently did not require exogeneous factors or accessory cells. The K562-acti...