Little is known about the role of vascular endothelial growth factor (VEGF) receptor-1 (VEGFR-1) in acute leukemia. In this study, using real-time PCR and ELISA, we found that VEGF and VEGFR-1 are highly expressed in U937 leukemia cells and primary leukemia cells (M4/M5 subtypes), which are associated with an increased migration rate and extramedullary disease. In order to elucidate the role of...

Nitric oxide (NO) has a central role in host defense against intracellular microbes. HLA-B27 has been shown to directly modulate host-microbe interaction in vitro, leading to the impaired elimination of Salmonella in human monocytic U937 cells. Here, we studied whether impaired elimination of Salmonella would result from differences in NO production between HLA-B27- and HLA-A2-transfected U937 ...

We analyzed the effect of recombinant human ¡nterleukin6 (IL-6), in combination with human recombinant interleukin la (IL-la), on the growth and differentiation of several human and mouse myeloid leukemic cell lines, specifically U937, HL-60, Ml, and its subclone Ml-3b-N, into macrophage-like cells. IL-6 and IL-1 inhibited the growth of U937, Ml, and Ml-3b-N in a dose-dependent manner. Treatme...

In this study, we investigated the functional role of Akt and c-jun-NH(2)-kinase (JNK) signaling cascades in apigenin-induced apoptosis in U937 human leukemia cells and anti-leukemic activity of apigenin in vivo. Apigenin induced apoptosis by inactivation of Akt with a concomitant activation of JNK, Mcl-1 and Bcl-2 downregulation, cytochrome c release from mitochondria, and activation of caspas...

Oxazaphosphorines belong to a group of alkylating agents. Mafosfamide cyclohexylamine salt (D-17272), 4-hydro-peroxy-cyclophosphamide (D-18864) and glufosfamide (D-19575, beta-D-glucose-isophosphoramide mustard) are new generation oxazaphosphorines. The objective of the present study was to compare the cytotoxic action of these oxazaphosphorine compounds against human histiocytic lymphoma U937 ...

Production of reactive oxygen species (ROS) by ischemic tissue after ischemia-reperfusion (I/RP) is an important factor that contributes to tissue injury. The small GTPase Rac1 mediates the oxidative burst, and ROS act on signaling pathways involved in expression of inflammatory genes. Because there is evidence implicating monocytes in the pathogenesis of I/RP injury, our objective was to deter...

Flavonoids, a vast group of polyphenols widely distributed in plants, are known to possess a range of biological activities and potential anti-tumor effects. X-linked inhibitor of apoptosis protein (XIAP) promotes the progression of leukemia by preventing tumor cells undergoing apoptosis. The present study investigated the potential effects and underlying mechanisms of pure total flavonoids fro...

We have found that an anti-CD11c monoclonal antibody (MAb) inhibits the respiratory burst induced in phorbol 12-myristate 13-acetate (PMA)-differentiated U937 cells as well as in human peripheral blood monocytes and neutrophils upon cell stimulation with concanavalin A. The MAb had no effect, however, when the added stimulus was fMet-Leu-Phe or PMA. Flow cytometry analyses indicated that concan...