Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The anti-proliferation effects of oridonin on acute promyelocytic leukemia (APL) cells and its mechanisms were studied in vitro. NB4 cells as well as fresh leukemia cells obtained from APL patients in culture medium were treated with different concentrations of oridonin. Cell growth inhibition, apoptosis and related pathways were assessed by MTT assay as well as flow cytometry (FCM) and western blot analysis. The data revealed that oridonin (over 16 micromol/L) could inhibit the growth of NB4 cells by induction of apoptosis. Marked changes of cell apoptosis were observed very clearly by using electron microscopy and DNA fragmentation analysis after the cells exposed to oridonin for 48 h; Western blotting showed cleavage of the caspase-3 zymogen protein (32-kDa) with the appearance of its 20-kDa subunit as well as a cleaved 89-kDa fragment of 116-kDa PARP when apoptosis occurred. The expression of Bcl-2 was down-regulated remarkably accompanied by the disruption of the mitochondrial membrane potential (delta(psi)m). The anti-proliferative and apoptosis-inducing effects by oridonin in fresh APL cells were also found remarkably using Trypan Blue dye exclusion method and Wright's staining. We concluded that oridoning has significant anti-proliferative and apoptosis-inducing effects on NB4 cells by activation of caspase-3 and cleavage of PARP as well as by down regulation of Bcl-2 and disruption of the delta(psi)m. Furthermore, oridonin demonstrated apparent cell growth inhibition effects on fresh APL cells in vitro. The results indicated that oridonin may serve as a potential anti-leukemia reagent.
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PMID:Apoptotic effect of oridonin on NB4 cells and its mechanism. 1601 88

All-trans retinoic acid (ATRA) induces complete remission in a high proportion of patients with acute promyelocytic leukemia (APL); however, the response is sometimes very slow. Furthermore, relapse and resistance to treatment often occur despite continued treatment with ATRA. Thereafter, combination treatment strategies have been suggested to circumvent these problems. The present study demonstrates that caffeic acid phenethyl ester (CAPE), a major component of honeybee propolis, enhanced ATRA-induced granulocytic differentiation in HL-60, a human promyelocytic cell line. The differentiation was assessed by Wright-Giemsa stain, nitroblue tetrazolium reduction, and membrane differentiation marker CD11b. In addition, CAPE enhanced ATRA-induced cell cycle arrest at the G1 phase by decreasing the association of cdk2-cyclin E complex. Finally, it was demonstrated that CAPE promoted the ATRA-mediated nuclear transcription activation of RARalpha assessed by EMSA assay and enhanced the expression of target genes including RARalpha, C/EBPepsilon, and p21 protein resulting in the differentiation development of leukemia. It is suggested that CAPE possesses the potential to enhance the efficiency of ATRA in the differentiation therapy of APL.
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PMID:Enhancement of caffeic acid phenethyl ester on all-trans retinoic acid-induced differentiation in human leukemia HL-60 cells. 1676 8

Recently, we have reported that 3-hydrogenkwadaphnin (3-HK), a diterpene ester isolated from Dendrostellera lessertii (Thymealeaceae), is very effective against leukemia cell lines without any detectable effects on normal cells (Moosavi et al., 2005b). In this study, we report that 3-HK induces G1 cell-cycle arrest, differentiation and apoptosis in APL NB4 cell line. Indeed, the drug between 24 to 96 h induced 7-65% growth inhibition of NB4 cells. Cell viability was also decreased by 2-55% between 24 to 96 h treatments with the drug, respectively. These effects of the drug were also dose-dependent. According to flow cytomtry results, 3-HK (15 nM) induced a significant G1-arrest up to 24 h which was consequently followed with appearance of sub-G(1) peak at 72 to 96 h. Hoechst 33258 staining and DNA fragmentation assays confirmed the occurrence of apoptosis among the treated cells. On the other hand, NBT reducing assay, Wright-Giemsa staining, phagocytic activity and expression of cell surface markers (CD11b and CD14) confirmed that the inhibition of proliferation is associated with differentiation especially toward macrophage-like morphology. Interestingly, 3-HK at 5 and 10 nM enhanced the effects of all-trans retinoic acid (ATRA) in NB4 cells. Based on these results, 3-HK might become an ideal candidate for treatment of APL patients pending full exploration of its biological functions.
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PMID:3-Hydrogenkwadaphnin induces monocytic differentiation and enhances retinoic acid-mediated granulocytic differentiation in NB4 cell line. 1712 8

Pneumocystis jiroveci (formerly carinii) pneumonia (PCP) is a serious opportunistic infection in children and adolescents with cancer. It was the most common cause of death among children receiving chemotherapy prior to the inclusion of PCP prophylaxis as part of standard care for children with leukemia. The incidence of PCP has decreased significantly since initiation of prophylaxis; however, breakthrough cases continue to occur. Hematologic malignancies, brain tumors necessitating prolonged corticosteroid therapy, hematopoietic stem cell transplantation, prolonged neutropenia, and lymphopenia are the most important risk factors for PCP in children not infected with HIV. Of children with leukemia, 15-20% may develop PCP in the absence of prophylaxis. Infection with P. jiroveci occurs early in life in most individuals. However, clinically apparent disease occurs almost exclusively in immunocompromised persons. Dyspnea, cough, hypoxia, and fever are the most common presenting symptoms of PCP. Chest radiography and high-resolution CT scans of the chest demonstrate a characteristic ground-glass pattern. Induced sputum analysis and bronchoalveolar lavage are the diagnostic procedures of choice. Gomori's methenamine-silver stain, Geimsa or Wright's stain, and monoclonal immunofluorescent antibody stains are most commonly used to make a diagnosis. However, identification of P. jiroveci DNA using polymerase chain reaction assays in bronchoalveolar lavage fluid is more sensitive. Trimethoprim-sulfamethoxazole (TMP-SMZ; cotrimoxazole) is the recommended drug for the treatment of PCP. Patients who are intolerant of TMP-SMZ or who have not responded to treatment after 5-7 days of therapy with TMP-SMZ should be treated with pentamidine. A short course of corticosteroids is recommended for moderate to severe cases of PCP within the first 72 hours after diagnosis. Mutations in the dihydropteroate synthetase gene may confer resistance to TMP-SMZ; however, the clinical relevance of these mutations is not well established. TMP-SMZ is the most commonly used agent for prophylaxis. Myelosuppression is the most important adverse effect of TMP-SMZ and the most frequent cause for choosing alternative prophylactic agents in children undergoing chemotherapy. Alternative agents for chemoprophylaxis include dapsone, aerosolized pentamidine, and atovaquone. Alternative prophylactic agents must be used in patients developing myelosuppression secondary to TMP-SMZ or dapsone.
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PMID:Management of Pneumocystis jiroveci pneumonia in children receiving chemotherapy. 1792 2

3-Hydrogenkwadaphnin (3-HK) (Fig. 1) is a daphnane-type diterpene ester isolated from the leaves of Dendrostellera lessertii (Thymelaeaceae) with differentiation and apoptotic potency among several leukemic cells without any measurable adverse effects on normal cells [Moosavi, M.A., Yazdanparast, R., Sanati, M.H., Nejad, A.S., 2005a. 3-Hydrogenkwadaphnin targets inosine 5'-monophosphate dehydrogenase and triggers post-G1 arrest apoptosis in human leukemia cell lines. Int. J. Biochem. Cell Biol. 37, 2366-2379]. In this study, we evaluated differentiating and apoptotic efficiency of a second new anti-proliferating agent from the same plant relative to 3-HK using acute myeloid leukemia (AML) KG1 cell line. 3-HK at 5-30 nM inhibited proliferation of KG1 cells after 24-96 h of treatment. NBT reducing assay and expression of cell surface markers (CD11b and CD14) confirmed that the inhibition of proliferation is associated with differentiation toward macrophage-like morphology. Regarding the relatively weaker potency of 3-HK in the induction of differentiation compared to that of the crude extract, we looked for additional compound(s) with similar properties in the crude extract. This effort led to isolation of the second compound from the leaves' extract with higher differentiating potency. The new compound inhibited proliferation of KG1 cells by almost 48+/-3.1% after 72 h of treatment with a single dose of 1.5 microg/ml. The treated cells differentiated along the monocyte/macrophage lineage based on the morphological features apparent after Wright-Giemsa staining, phagocytic activity and expression of cell surface markers as analyzed by flow cytometry. On the other hand, the results indicated that exposure of KG1 cells to either 3-HK or the new compound for 3-4 days induced apoptosis as assayed qualitatively by acridine orange/ethidium bromide (Ao/EtBr) double staining, agarose gel electrophoresis and quantitatively by Annexin-V technique and sub-G1 DNA staining using flow cytometry. Based on the present data, these two active constituents of D. lessertii have the novelty of being further evaluated for pharmaceutical applications.
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PMID:3-Hydrogenkwadaphnine, a novel diterpene ester from Dendrostellera lessertii, its role in differentiation and apoptosis of KG1 cells. 1882 78

This study was aimed to investigate the effects of low frequency and power ultrasound combined with adriamycin on apoptosis of drug-resistant leukemia cell line K562/A02 in vitro, to find out the parameters of optimal exposure, and to explore the possible mechanism reversing drug-resistance of K562/A02 cells. The K562/A02 cells in logarithmic growth phase were used in experiments. The experiments were divided into 4 groups: group control, group adriamycin (A02) alone, group ultrasound (US) alone and group A02+US. The trypan blue dye exclusion test and MTT assay were used to determine the cell viability; Wright's staining was used to detect the apoptosis; the flow cytometry was used to analyze the drug concentration, and the scanning electron microscopy was used to observe the changes of cell surface. The results showed that the significant differences in cell viability, intracellular adriamycin concentration and changes of cell membrane were found between ultrasound-treated and untreated cells in the presence of various concentration of adriamycin. The exposure to ultrasound at 20 kHZ, 0.25 W/cm2 for 60 seconds could obviously decrease LC50 of adriamycin to K562/A02 cells, while the exposure to ultrasound at 20 kHZ, 0.05 W/cm2 for 60 seconds could kill K562/A02 cells at once. After being treated by low frequency ultrasound, the small holes with diameter about 1-2 microm in the cell surface appeared. The ultrasound increased the adriamycin concentration in the cells, accelerated the formation of apoptotic bodies, and promoted apoptosis of adriamycin-resistant cells. It is concluded that the ultrasound at optimal parameters enhances inhibitory effect of adriamycin on drug-resistant cell line, thereby reverses drug-resistance of drug-resistant cell line through sound-hole effect in tumor cells resulting from ultrasound induced cavitation.
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PMID:[Enhancement of reversing drug resistance of K562/A02 cells to adriamycin by ultrasound-induced cavitation]. 1909 28

This study was aimed to explore whether the apoptosis of leukemia cells can be induced by targeting silencing nucleostemin gene in vitro. HL-60 cells were taken as the model, and were directly transfected with nucleostemin short hairpin RNA (NS-shRNA). Sequences unrelated with NS gene were taken as control. The blocking effect of NS-shRNA was detected by RT-PCR, the morphology changes in living cells were observed under inverted microscope, and the changes of cell shape and nucleus were detected by Wright-Giemsa staining. The amount of apoptotic cells were assayed by flow cytometer (FCM) and TUNEL technique, and the positive rate of apoptosis was determined meanwhile. The results showed that two NS-shRNA were synthesized in vitro, and the more effective one was selected to be transfected into HL-60 cells. The blocking rate of NS-mRNA reached to 74.94%. After transfection for 48 hours, Wright-Giemsa staining showed nuclear fragmentations and "apoptosis body" in cells. The apoptosis rate in transfected group detected by flow cytometry and TUNEL method were (25.32 +/- 3.06)% and (27.3 +/- 3.21)% respectively, but were only (3.12 +/- 0.38)% and (3.30 +/- 1.52)% in control group, the difference between the transfected group and the control group was significant (p < 0.01). It is concluded that the apoptosis of HL-60 leukemia cells can be induced by the silencing NS gene expression in vitro, which provides a theoretical basis for using NS gene as a candidate target gene in therapy of malignant tumor.
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PMID:[Effects of silent nucleostemin gene expression on apoptosis of HL-60 cells in vitro]. 1937 59

This study was aimed to compare partial biological characteristics of bone marrow mesenchymal stem cells (BMMSCs) in AML patients, AML patients with complete remission (CR) and non-leukemia patients. The bone marrow (BM) MSCs were divided into 3 groups: group of MSCs from AML patients, group of MSCs from AML patients with CR, group of MSCs from non-leukemia patients. The morphologic features of MSCs were observed by light microscopy; CFU-F numbers of MSCs were counted after Wright-Giemsa staining in situ; the fusion times of MSCs were determined; the growth curves of MSCs were drawn by counting cell numbers; the immunophenotypes and cell cycle of MSCs were detected by flow cytometry; the DI values of MSCs were calculated. The results showed that the morphologic features of MSCs in 3 groups did not display difference; there was significant difference (p < 0.01) of CFU-F numbers in 3 groups, while CFU-F number of MSCs in AML group was minimal; there was significant difference of MSC fusion time in 3 groups, while fusion time of MSCs in AML group was most long; the growth curves of MSCs in 3 groups were similar; MSCs in 3 groups highly expressed CD105 and CD106, but not expressed CD45; the cell distribution ratios at phase of G(0)/G(1) for MSCs in 3 groups were 89.9 +/- 4.0%, 90.2 +/- 3.0% and 91.0 +/- 3.0% respectively; the DI values of MSCs in 3 groups were between 0.9 and 1.1. It is concluded that no significant difference of biological characteristics of the second generations of MSCs is found between those in leukemia and non-leukemia patients.
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PMID:[Comparison of biological characteristics of bone marrow mesenchymal stem cells in acute myeloid leukemia with those from non-leukemia]. 1937 74

This study was aimed to investigate the conditions of culturing in vitro mesenchymal stem cells (MSCs) derived from bone marrow of children with acute leukemia and the biological characteristics of MSCs from leukemia children. The bone marrow MSCs of acute leukemia children were isolated by density gradient centrifugation combined with adherent segregating method and cultured in DMEM/F12. The morphology of Wright stained MSCs was observed under inverted microscope. Cell surface markers were analyzed with flow cytometry. The growth characteristic features of cultured MSCs was measured with MTT method. Induced adipogenic and osteogenic differentiation of MSCs in appropriate induction media was observed. The results indicated that BM-MSCs of acute leukemia children could be successfully cultured in vitro in appropriate conditions. At 24 hours of culture the MSCs began to adhere to wall, grew in colony and appeared in different shapes. As the culture lasted, the MSCs proliferated continuously and shaped in fusiform. After 2 - 3 weeks of culture, MSCs covered the bottom of culture flask. The analysis of growth feature showed that MSCs were in latency for 3 days, and then entered into growth period. After 8 days of culture the growth of MSCs showed to be in plateau stage. The shape of MSCs in 1st and 2nd generation showed to be heterogeneous but the 3rd generation to be homogeneous with long-fusiform. Cells were arranged in shape of whirlpool or radiation. The surface marker analysis showed that the MSCs were positive for CD105, CD29, CD13, but negative for CD34, CD45, CD14 and HLA-DR. The MSCs from leukemia children could be induced into adipocytes and osteocytes in appropriate conditions. It is concluded that (1) MSCs derived from children with acute leukemia can be successfully cultured and passaged in vitro; (2) MSCs from leukemia children not received chemotherapy are more successfully cultured in vitro than those received chemotherapy; (3) the common biological characteristics of MSCs from children with acute leukemia are same as the MSCs from healthy person.
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PMID:[Biological characteristics of bone marrow-derived mesenchymal stem cells in children with acute leukemia]. 1954 97

In the present study we investigated the in vitro apoptosis inducing effects of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) ligand ciglitazone (CGZ) on acute promyelocytic leukemia (APL) NB4 cells and its mechanisms of action. The results revealed that CGZ (10-50 micromol/l) inhibited the growth of leukemia NB4 cells and caused apoptosis in a time- and dose-dependent manner. Apoptosis was observed clearly by flow cytometry (FCM) and DNA fragmentation analysis. After treatment by CGZ for 48 h, the percentage of disruption of mitochondrial membrane potential (Deltapsim) was increased in a dose-dependent manner. Western blotting demonstrated the cleavage of caspase-3 zymogen protein and a time-dependent cleavage of poly (ADP-ribose) polymerase (PARP). The results also demonstrated that PPAR-gamma expression was increased concomitantly when apoptosis occurred, and that CGZ-induced apoptosis was inhibited by the PPAR-gamma antagonist GW9662, suggesting a PPAR-gamma dependent signaling pathway in CZG-induced cell death. Moreover, CGZ treatment remarkably downregulated the expression of the X-linked inhibitor of apoptosis protein (XIAP), which was inhibited by GW9662. Of note, a small-molecule XIAP antagonist (1396-12) mimicked the effect of CGZ-induced apoptosis via activation of caspase-3, 7 and 9. The apoptosis-inducing effects by CGZ on fresh APL cells were also found to be remarkable by using FCM and Wright's staining observation. Taken together, our results suggest that downregulation of XIAP and activation of capase-3 play an important role in mediating the PPAR-gamma-dependent cell death induced by CGZ in APL cells. These data provide a novel insight into potential therapeutic strategies for treatment of leukemia.
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PMID:Activation of peroxisome proliferator-activated receptor-gamma induces apoptosis on acute promyelocytic leukemia cells via downregulation of XIAP. 1978 96


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