In vitro anti-proliferative and apoptotic activity of different fractions of Artemisia armeniaca

Anti-proliferative properties have been reported for certain species of the genus Artemisia. In this study, we investigated the cytotoxic and apoptotic effects of n-hexane, CH2Cl2, EtOAc, n-BuOH and H2O fractions obtained from a crude methanol extract of A. armeniaca on two myeloid cell lines, apoptosis-proficient HL60 cells and apoptosis-resistant K562 cells; in addition, J774 cells were used as a control. Among the solvent fractions of A. armeniaca, the CH2Cl2 fraction was found to have the largest anti-proliferative effect on cancer cells. The IC50 values obtained using an MTS assay for the CH2Cl2 fraction were 75 and 130 µg/ml for HL-60 cells and K562, respectively. The control cells were not significantly affected by this fraction. A flow cytometry histogram of cells treated with the CH2Cl2 fraction of A. armeniaca revealed a sub-G1 peak. DNA fragmentation, increased protein levels of Bax and cleavage of the poly (ADP-ribose) polymerase (PARP) protein confirmed the induction of apoptosis in cells after a 48-h exposure to the CH2Cl2 fraction. Our results corroborate the cytotoxic and apoptotic effects of the CH2Cl2 fraction of A. armeniaca on K562 and HL-60 cancer cell lines.

Human Tumor Cells Apoptosis Induced by Dihydroartemisinin and Its Molecular Mechanism / 中国药房

OBJECTIVE:To study the apoptosis of human leukemic cells induced by Dihydroartemisinin and its molecular mechanism.METHODS:Human leukemia K562 cells were treated by Dihydroartemisinin.The inhibitory effect on cell proliferation was assayed by MTT.Fluorescence microscopy was applied to observe the presence of apoptosis.The expression of caspase-3 was assayed with reverse transcription-polymerase chain reaction(RT-PCR).Levels of mitochondrial and cytoplasmic cytochrome C were determined using Western blot.RESULTS:After treatment with Dihydroartemisinin for 48 hours,the IC50 values of human leukemia K562 cells were 8? 10-5mol? L-1 detected at a wavelength of 570nm by MTT.Distinct morphology changes of cell apoptosis such as karyopyknosis and conglomeration were observed by Hoechst33342/PI staining.RT-PCR assay showed the expression of Caspase-3.Western-blot detection showed the decrease of mitochondrial cytochrome C concentration but the positive expression of cytoplasmic cytochrome C concentration.CONCLUSION:Dihydroartemisinin could inhibit proliferation and induce apoptosis of human leakemic K562 cells,this may partially attributed to the promotion of the delivery of cyt-c and the activation of caspase-3.

Association of dexamethasone-induced apoptosis of G|1-arrest of human leukemic CEM cells with polyamine deficit

The effects of DFMO or/and putrescine on the dexamethasone-induced apoptosis of CEM cells were studied to investigate the role of polyamines in anti-leukemic glucocorticoid action. Dexamethasone-induced apoptosis was preceded by significant decreases of cellular polyamine contents and putrescine uptake activity. But DFMO produced decreases of putrescine and spermidine contents and marked increase of putrescine uptake activity, but did not induce apoptosis. However, dexamethasone and DFMO, respectively, induced G|1-arrest in cell cycle and hypophosphorylation of pRb, resulting in the increase of G|1 to S ratio and decrease of CEM cell count. DFMO enhanced the dexamethasone-induced apoptosis and G|1-arrest. On the other hand, putrescine little affected the apoptotic and G|1-arresting activities of dexamethasone, but almost suppress the effects of DFMO and also the DFMO-dependent enhancement of dexamethasone effects. These results suggested that the dexamethasone-induced apoptosis to be associated with pRb hypophosphorylation and G|1-arrest in CEM cells might be ascribed to the concomitant decreases of cellular polyamine contents and putrescine uptake activity.

In vivo and in vitro study of aescin in L1210 murine acute lymphoid leukemia cells / 中草药

Objective To explore aescin's inhibition of in vitro proliferatim in L1210 murine acute lymphoid leukemia cells and its in vivo antileukemic effects.Methods MTT assay was used to determine the anti-proliferative effect in vitro;Leukemia transplant models were used to test the antileukemic effect. Mice inoculated with L1210 cells were treated with ten daily doses of aescin or/and each other day of DOX, and were observed for survival.Antileukemic effects were assessed by calculating the extension of lifespan. Results Aescin(20～60?g/mL) was found to be able to inhibit the proliferation of L1210 cells.The effects were in a dose- and time- dependent manner.The IC_(50) value of aescin in L1210 cells after 72 h was (24.86?2.23)?g/mL.In vivo study showed that after treating the L1210 cells bearing mice with higher, middle,and low dosage(4.5,3.5,and 2.5 mg/kg) of aescin for ten consecutive days,The extension of lifespan were 25.8%(P

Programmed Cell Death of Leukemic Cell(HL-60) Induced by Quercetin in Vitro / 中成药

To study anti-leukemic cell mechanism of quercetin, its effects on the proliferation activity of human leukemic cell (HL-60) in vitro were investigated by flow cytometric method and MTT assay.The studies indicated that quercetin showed strong suppression on the proliferation activity of leukmic cells in the time and dose-dependent manner. The value of IC50 and 95% confidence limit were 43. 1 (30. 5~60. 8)?mol/L after 48h. The flow cytometry indicated that it could induce programmed cell death of leukmia HL-60 ecll.

Establishment of a long-term cytotoxic T cell line against syngeneic mouse leukemia and its biological characteristics / 中国免疫学杂志

Cytotoxic T lymphocytes (CTL) derived from the spleen of SW-1 mice immunized in vivo with syngeneic mouse leukemia clonal cells LAC-1 were cultured in TCGF containing media and tested for cytotoxicity against LAC-1 cells in a routine ~(51)Cr-release assay. The experimental results showed that the CTL cell line was proved to be Thy 1 and Lyt 2, and therefore they were considered to be of T cell lineage. When CTL were expanded in the presence of TCGF, an augmented cytolytic activity in parallel with the increase of Thy 1 and Lyt 2 cells was shown. This cytotoxic T cell line had been maintained in a long-term culture for nearly 1 year and retained the initial reactivity. Specificity studies of the CTL showed that the cell line was highly specific for LAC-1 cells and its parent line L783 Leukemic cells and the cytolytic effect was H-2 restriction. The cytotoxicity of the CTL could be blocked by conventional or monoclonal antibodies against cell surface antigen (TSA) of LAC-1 cells. Antisera against H-2 antigens, shared by LAC-1 cells, also showed blocking activity.

Study of Anti-CD9, CD10 immunotoxins to kill leukemiccell and the effect, on hemopoiesis / 中国免疫学杂志

Immunotoxin consists of the antibody, which can specifically recognize relative antigen on the surface of leukemic cell, and intact ricin, which kill cell. It is very profitable to eliminate leukemic cell from bone marrow for prophylaxis of leukemia relapse after bone marrow transplantation. In the study, we reported that clongoenic leukemic cell (Nalm-6) were eliminated by two different immunotoxins (with CD9 and CD10). The inhibiting effect of immunotoxins in useful dose on the proliferation of hemopoietic progenitor cells (CFU-mix, BFU-E and CFU-GM) was not obviously.It is probably that immunotoxins will be used in autologous bone marrow transplation.

PURGING OF HUMAN LEUKEMIC CELL LINES IN VITRO WITH PHOTOCARCINORIN-MEDIATED PHOTOSENSITIZATION / 解放军医学杂志

5.16 log of K562, U937, HIMeg and HL60 cells, respectively, but spare 23.37 ? 25.66% of normal CFU-GM (0.63 log killing). When HL60 cells mixed with normal mononucleated bone marrow cells in 1:9 ratio were studied, the killing of HL60 colonies was more than 4.29 log. The result suggested that photocarcinorin plus light could eliminate leukemic progenitors, and might be used in clinical ABMT. Several factors that might affect the photosensitization effect on cells were discussed.