Introduction: Cancer is, in essence, a genetic disease and is the second leading cause of death globally. Fortunately, many common types of cancer are treatable if detected early and of course there are many medications and treatments available today. Among the new methods to treat cancer, radiotherapy seems to be hopeful in patients with malignancies. This work investigates th...

The beta 2 integrin lymphocyte function-associated antigen 1 (LFA-1) mediates activation-dependent adhesion of lymphocytes. To investigate whether lymphocyte-specific elements are essential for LFA-1 function, we expressed LFA-1 in the erythroleukemic cell line K562, which expresses only the integrin very late antigen 5. We observed that LFA-1-expressing K562 cannot bind to intercellular adhesi...

Basic fibroblast growth factor (bFGF) and transforming growth factor-beta 1 (TGF-beta) have both been shown to act on hematopoietic progenitor cells. bFGF is a hematopoietic cytokine that acts on progenitor cells in concert with other cytokines to promote their proliferation. TGF-beta induces erythroid differentiation in K562 cells. To determine whether bFGF might act on progenitor cells by ant...

We investigated the influence of the activation state of integrin alpha 5 beta 1 on its dependence on the PHSRN synergy site for binding to RGD in fibronectin. K562 and MV3 cells lacked alpha v beta 3 expression and adhered to fibronectin through alpha 5 beta 1. Mel57 cells adhered through alpha v beta 3 and alpha 5 beta 1. A recombinant fibronectin polypeptide, containing five type III repeats...

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 compared the expression of the ras protooncogene family (H-, K-, and N-ras) in leukemia cell differentiation utilizing as a model K562 and HEL erythroleukemia cells treated either with 1-beta-arabinofuranosylcytosine or 12-O-tetradecanoylphorbol-13-acetate (TPA). 1-beta-D-Arabinofuranosylcytosine induced terminal erythroid differentiation of K562 cells, while TPA induced myeloid differe...

Purpose: To prepare beta-cryptoxanthin-loaded nanoliposomes and evaluate their anti-proliferative activity in leukemia K562 cell line, compared to free beta-cryptoxanthin. Methods: Beta-cryptoxanthin-loaded nanoliposomes were prepared by extrusion method. Morphological characterization of the nanoliposomes was performed by cryo-transmission electron microscopy (cryo-TEM). The anti-proliferation...

Herbimycin A, a benzoquinonoid ansamycin antibiotic, is found to reduce intracellular phosphorylation by tyrosine protein kinase. The human chronic myelogenous leukemia cell line K562 expresses a structurally altered c-abl protein with tyrosine kinase activity. When K562 cells are induced to undergo erythroid differentiation by hemin, reduction in the intracellular level of tyrosine phosphoryla...

Platelet alpha granules contain several growth factors such as the transforming growth factor beta (TGF-beta) that are released during blood clotting and are thought to participate in the repair of tissue injury; however, the site of synthesis of platelet TGF-beta has not been demonstrated. We studied TGF-beta expression during megakaryoblastic differentiation of the chronic myeloid leukemia ce...

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(-6) M). Fluoxymesterone caused a prominent enhancement of K562 colony growth, whereas estriol had no effect. Stimulation by triiodothyronine was maximal at 1...