• BMB Reports
• /
• 제49권1호
• /
• pp.63-68
• /
• 2016

The serine/threonine kinase mTOR is essential for the phosphoinositide 3-kinases (PI3K) signaling pathway, and regulates the development and function of immune cells. Aberrant activation of mTOR signaling pathway is associated with many cancers including leukemia. Here, we report the contributions of mTOR signaling to growth of human leukemic cell lines and mouse T-cell acute leukemia (T-ALL) cells. Torin, an ATP-competitive mTOR inhibitor, was found to have both cytotoxic and cytostatic effects on U-937, THP-1, and RPMI-8226 cells, but not on Jurkat or K-562 cells. All cells were relatively resistant to rapamycin even with suppressed activity of mTOR complex 1. Growth of T-ALL cells induced by Notch1 was profoundly affected by torin partially due to increased expression of Bcl2l11 and Bbc3. Of note, activation of Akt or knockdown of FoxO1 mitigated the effect of mTOR inhibition on T-ALL cells. Our data provide insight on the effect of mTOR inhibitors on the survival and proliferation of leukemic cells, thus further improving our understanding on cell-context-dependent impacts of mTOR signaling. [BMB Reports 2016; 49(1): 63-68]

• BMB Reports
• /
• 제36권4호
• /
• pp.387-389
• /
• 2003

The young developing leaves of willow (Salix safsaf, Salicaceae) trees have antileukemic activity. After a 24-h incubation in vitro, the crude water extracts of the leaves killed a majority of the blasts of acute myeloid leukemia (AML, 73.8%).

• 동의생리병리학회지
• /
• 제17권3호
• /
• pp.643-647
• /
• 2003

The Methylene Chloride(MC) fraction of Trichosanthis kirilowii Maxim has been investigated anti-tumor activities in vitro. The MC fraction of Trichosanthis kirilowii Maxim significantly inhibited the proliferation of human leukemic U937 cell with an IC50 of approximately 10μg/ml in a dose-dependent manner. We found that the MC fraction upregulated of caspase9 and caspase-3 activity and cleaved PARP expression but it didn't affect bax and bcl-2. which were demonstrated by western blot analysis. Taken together, these results exerted that the MC fraction suppessed human leukemic U937 cell proliferation by inducing apoptosis, suggesting the MC fraction of Trichosanthis kirilowii Maxim is possible to show anti-cancer activity in vivo.

• Asian Pacific Journal of Cancer Prevention
• /
• 제17권12호
• /
• pp.5139-5145
• /
• 2016

There has been an increment in the number of studies focused on marine bioactive materials. Many peptides and other biomaterials with anticancer potential have been extracted from various marine animals. Artemia extracts have found uses in sun-light protection cosmetics and anti-aging products. However, contents of biochemical compounds in Artemia spp. and molecular mechanisms of have not been clearly studied in leukemic cells in vitro. In this work, we isolated and purified proteins of Artemia Urmiana. Six clear fractions (A-F) observed on DEAE-cellulose chromatography were assayed for effects on cell growth, differentiation and apoptosis using the human leukemic HL-60 cell line. Cell proliferation analysis by MTT and BrdU assays indicated that did not affect cells, growth. Cells treated with crude extract and fractions A, B and C, but not E and F (up to $100{\mu}g/mL$), exhibited increase of cell growth in a dose dependent manner. Stimulatory effects of fraction D were observed at concentrations of $10{\mu}g/mL$ and above. In nitro blue tetrazolium (NBT) reduction assays, treatment with $100{\mu}g/mL$ of fraction E or F for 96 hr increased the fraction of differentiated cells up to $14.8{\pm}3.56%$ and $16.5{\pm}2.08%$ respectively. Combination of those fractions with retinoic acid had significant synergistic effects on the differentiation of cells ($56.8{\pm}3.7%$ and $67.4{\pm}4.2%$, $p{\leq}0.01$). Annexin-V FITC staining for apoptosis and flow cytometric assays indicated induction of apoptosis by fractions E and F up to 23.8 and 31.8% of cells.

• Asian Pacific Journal of Cancer Prevention
• /
• 제15권1호
• /
• pp.475-481
• /
• 2014

Background: Pereskia sacharosa is a genus of cacti widely used in folk medicine for cancer-related treatment. Anti-proliferative effects have been studied in recent years against colon, breast, cervical and lung cancer cell lines, with promising results. We here extended study of anti-proliferative effects to a blood malignancy, leukemia. Materials and Methods: Two leukemic cell lines, MV4-11 (acute myeloid leukemia) and K562 (chronic myeloid leukemia), were studied. $IC_{50}$ concentrations were determined and apoptosis and cell cycle regulation were studied by flow cytometric analysis. The expression of apoptosis and cell-cycle related regulatory proteins was assessed by Western blotting. Results: P sacharosa inhibited growth of MV4-11 and K562 cells in a dose-dependent manner. The mode of cell death was via induction of intrinsic apoptotic pathways and cell cycle arrest. There was profound up-regulation of cytochrome c, caspases, p21 and p53 expression and repression of Akt and Bcl-2 expression in treated cells. Conclusions: These results suggest that P sacharosa induces leukemic cell death via apoptosis induction and changes in cell cycle checkpoint, thus deserves further study for anti-leukemic potential.

• The Korean Journal of Physiology and Pharmacology
• /
• 제5권1호
• /
• pp.79-86
• /
• 2001

Recent clinical studies have shown that a high proportion of patients with acute promyelocytic leukemia (APL) achieve complete remission after treatment with all-trans retinoic acid (ATRA). However, most patients who receive continuous treatment with ATRA relapse and develop ATRA-resistant leukemia. Dendritic cells (DCs) are important antigen-presenting cells in the development of antileukemic T-cell responses. In this study, we investigated the strategies to overcome ATRA resistance of APL cells by inducing the differentiation of DCs from human leukemic cell lines for the developtment of adoptive immunotherapy. CD83 was used as a mature DC marker in this study and the expression of CD83 mRNA was determined by RT-PCR method. The promyelocytic leukemic cell line HL-60, B lymphoblast cell lines RPMI 7666 and NC-37 could be induced to dendritic cells in vitro. Treatment of HL-60 with phorbol 12-myristate 13-acetate (PMA) resulted in the expression of myeloid-related DC phenotypes, while treatment of RPMI 7666 with fms-like tyrosine kinase 3 ligand (Flt3-ligand, FL) and treatment of NC-37 with PMA and FL led to the expression of lymphoid-related DC phenotypes. In conclusion, myeloid-related DC phenotypes and lymphoid-related DC phenotypes could be generated from HL-60, NC-37 and RPMI 7666 cell lines, respectively. These DC phenotypes can potentially be used to generate antileukemic T cells in vitro for adoptive immunotherapy.

• Toxicological Research
• /
• 제18권3호
• /
• pp.275-283
• /
• 2002

Fungal metabolite, gliotoxin is an epipolythiodioxopiperazin (ETP) class and has various roles including immunomodulatory and apoptotic effects. This study was designed to evaluate the mechanism by which gliotoxin exerts the apoptosis on human promyelocytic leukemic HL-60 cells. Herein, we demonstrated that the gliotoxin decreased the cell viability in a time-dependent manner Gliotoxin-induced cell death was confirmed us apoptosis characterized by chromatin condensation and ladder-pattern fragmentation of genomic DNA. Gliotoxin increased the catalytic activities of caspase-3 and caspase-9. Activation of caspase-3 was further confirmed by degradation of procaspase-3 and poly(ADP-ribose) polymerase (PARP) by gliotoxin in HL-60 cells. Furthermore, gliotoxin induced the changes of mitochondrial transmembrane potential (MTP). Antioxidants, including GSH and NAC, markedly inhibited apoptosis with conistent suppression of enzymatic activity of caspase-3, caspase-9, and MTP loss in gliotoxin-treated cells. Taken together, we suggest that gliotoxin function as an oxidant and ploys proapoptotic roles in HL-60 cells via activation of intrinsic caspase cascades as well as mitochondrial dysfunction.

• 대한약학회:학술대회논문집
• /
• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
• /
• pp.161.2-161.2
• /
• 2002

• Advances in Traditional Medicine
• /
• 제5권1호
• /
• pp.21-28
• /
• 2005

The leaf extracts of Araucaria bidwillii Hook. (Araucariaceae) were evaluated for their cytotoxic effect in various human cancer cell lines. Preliminary investigation by brine shrimp lethality assay indicated that $LC_{50}$ value of various successive extracts were found to be less than $1000\;{\mu}g/ml$, where the ethyl acetate extract showed maximum activity of less than $100\;{\mu}g/ml$. Further cytotoxic evaluation of various leaf extracts of Araucaria bidwilli Hook was carried out in four different human cancer cell lines-acute myeloblastic leukemia (HL-60), chronic myelogenic leukemia (K-562), breast adenocarcinoma (MCF-7) and cervical epithelial carcinoma (HeLa). Cytotoxicity was assessed by trypan blue dye exclusion method and 3-(4,5-dimethyl thiazole-2yl)-2,5-diphenyl tetrazolium bromide (MTT) reduction assay. From the present investigation it was found that the ethyl acetate and methanol extract of Araucaria bidwilli Hook was found to be more effective in leukemic cell lines and was less effective in MCF-7 and HeLa. The $IC_{50}$ value of the ethyl acetate extract in leukemic cell lines was found to be $28.18\;and\;34.64\;{\mu}g/ml$ and methanol extract was found to be $33.11\;&\;39.81\;{\mu}g/ml$. It can be concluded that various extract from the leaves of Araucaria bidwillii Hook. posses cytotoxic activity tested in brine shrimps and various human carcinoma cell lines.

• The Korean Journal of Physiology and Pharmacology
• /
• 제1권4호
• /
• pp.457-466
• /
• 1997

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.