scholarly journals DJ-1 Plays an Important Role in Homoharringtonine-Induced Apoptosis of Imatinib-Resistant Chronic Myeloid Leukemia Cells

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 5956-5956
Author(s):  
Xuan Zhou ◽  
Na Xu ◽  
Rong Li ◽  
Lin Li ◽  
Li Ding ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Molecular Mechanisms ◽  
Annexin V ◽  
K562 Cells ◽  
Molecular Therapy ◽  
Leukemia Cells ◽  
Control Group ◽  
Imatinib Resistant ◽  
Induced Apoptosis

Abstract Background and Objective: Although the treatment of chronic myeloid leukemia (CML) has improved since the introduction of tyrosine kinase inhibitors (TKI), cases of resistance have been reported and resulted in challenges to the treatment. Recent studies have suggested that Homoharringtonine (HHT), a cephalotaxine ester, has demonstrated a clinical activity in imatinib-resistant CML patients, however, the molecular mechanisms underlying this phenomenon are unknown. Our previous study found that treatment with HHT significantly increased apoptosis of K562 cells. Moreover, the protein DJ-1, identified by two-dimensional polyacrylamide gel electrophoresis and mass spectrometry, was demonstrated to decrease after HHT treatment. Therefore, we performed the experiment to address the hypothesis that DJ-1 might play an important role in Homoharringtonine-induced apoptosis of Imatinib-resistant chronic myeloid leukemia cells Methods and Results: To find the pivotal protein by HHT, Imatinib-resistant K562 cells were treated with HHT (10 ug/ml) for 5 h, 12 h, 24 h respectively and the control group without HHT were harvested to assess apoptosis with Annexin V-FITC and propidium iodide per the manufacturer’s protocol and analyzed by flow cytometry. The data indicated a time dependent induction of apoptosis by HHT, with the number of apoptotic cells (FITC-Annexin-V and PI double-positive cells) significantly increasing from 2.2± 1.5 % in control to 35.9 ± 6.7% in cells treated with HHT for 24 h (P<0.01). The protein DJ-1 expression change upon HHT treatment which were analyzed with western blot, found that the protein level of DJ-1 had significantly decreased after the treatment of HHT for 24 h. Furthermore, primary cells from six CML patients and three healthy donors were obtained with informed consent and divided into three groups: the CML-CP group (three newly diagnosed patients in the chronic phase), the imatinib-resistant CML group(three imatinib-resistant patients in the blastic phase) and the control group. Mononuclear cells were all cultured in vitro in the absence and presence of 10 mg/ml HHT for 5 h and 24 h. The results showed that DJ-1 expression in primary leukemia cells (both CML-CP group and imatinib-resistant CML group) were found to be decreased after HHT treatment and the expression level of DJ-1 seemed lower in the healthy donor as compared to primary CML cells, moreover, the protein changes induced by HHT were significantly different among three groups and the protein changes were not as significant in CML-CP cells as in imatinib-resistant CML cells (P<0.05). Conclusions: These findings indicated that DJ-1 might play an important role in Homoharringtonine-induced apoptosis of Imatinib-resistant chronic myeloid leukemia cells. Further study may help to assess a promising potential of this protein to be used as a target for a molecular therapy. Disclosures No relevant conflicts of interest to declare.

Bcr-Abl-Mediated Suppression of Normal Hematopoiesis in Chronic Myeloid Leukemia: Involvement of a Modified Form of NGAL.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 2869-2869
Author(s):  
Hui Lin ◽  
Xiaohong Leng ◽  
Tong Sun ◽  
Giuseppe Monaco ◽  
Clifton Stephens ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Hematopoietic Cells ◽  
K562 Cells ◽  
Soft Agar ◽  
Leukemia Cells ◽  
Active Process ◽  
Culture Studies ◽  
Induced Apoptosis

Abstract The BCR-ABL oncogene plays an essential role in chronic myeloid leukemia (CML). In NOD/scid mice injected with soft agar clones of a human CML cell line (K562), we observed a leukemia syndrome involving not only leukemia but also a severe reduction of normal mouse hematopoiesis (Lin et al., Oncogene, 2001). Some of these mice died of a wasting syndrome that involved suppression of hematopoiesis without extensive tumor cell invasion of the spleen and marrow. In CML patients, since normal hematopoietic cells in marrow and spleen are replaced with proliferating leukemic blasts, we postulate that this is an active process mediated by the leukemia cells. The lipocalin 24p3 is secreted by mouse hematopoietic cells deprived of IL-3, resulting in apoptosis induction in a variety of hematopoietic cells including bone marrow cells (Devireddy et al., Science, 2001). We found that BCR-ABL+ mouse hematopoietic cells induce a persistent secretion of a modified form of 24p3 (21 kDa). Co-culture studies show that BCR-ABL+ cells induced apoptosis in BCR-ABL negative cells. Importantly, BCR-ABL+ hematopoietic cells are resistant to apoptosis under the same conditions. Conditioned medium (CM) from BCR-ABL+ cells expressing anti-sense/siRNA 24p3 or CM mixed with 24p3 antibody have reduced apoptotic activity for target cells. We also found that the expression of the Bcr-Abl oncoprotein and its tyrosine kinase are required for induction of 24p3 expression. Leukemic mice induced by BCR-ABL+ cells expressing anti-sense/siRNA 24p3 have increased levels of normal hematopoiesis (marrow and spleen erythropoiesis and blood platelet levels) and reduced invasion of leukemia cells in marrow and spleen tissues, but the leukemia cells readily invade liver and the abdomen as ascites (Lin et al, Oncogene, 2005). These findings indicate that suppression of normal hematopoiesis in BCR-ABL induced leukemia is an active process involving the apoptotic factor 24p3, raising the possibility that similar factors are involved in BCR-ABL+ CML patients. We have found that the K562 clones (Lin et al. 2001) have enhanced expression of NGAL (neutrophil gelatinase-associated lipocalin, human homologue of 24p3) transcripts compared to uncloned K562 cells. We generated additional soft agar K562 clones, each with different expression levels of NGAL transcripts. NOD/scid mice injected with the clone (C5) of K562 cell line expressing a high level of NGAL had severe depression of hematopoiesis and significantly shorter survival time as compared with mice injected with parental K562 cells and a clone (C6) expressing a low level of NGAL. Co-culture studies showed that the C5 K562 clone also induced apoptosis in BCR-ABL negative cells. We detected two glycosylated forms of NGAL/24p3 migrating at 24 kDa and 21 kDa on SDS-PAGE. The 21 kDa form is the major form in CM from mouse BCR-ABL+ cells and K562 clones. Our preliminary data with CML patient samples showed that levels of 21 kDa NGAL protein in bone marrow fluid correlated with BCR-ABL/ABL ratio. Further studies with more patient samples are ongoing to confirm the role of NGAL in suppressing normal hematopoiesis in CML patients and to determine the structural change(s) that leads to the modified form of 24p3/NGAL secreted by CML cells.

Effect of Dasatinib on Genes Related to Mitotic Catastrophe Pathway in Chronic Myeloid Leukemia Cells

2020 ◽  
Vol 20 ◽  
Author(s):  
Sezgi Kipcak ◽  
Buket Ozel ◽  
Cigir B. Avci ◽  
Leila S. Takanlou ◽  
Maryam S. Takanlou ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Kinase Inhibitors ◽  
Fusion Gene ◽  
Philadelphia Chromosome ◽  
K562 Cells ◽  
Mitotic Catastrophe ◽  
Control Group ◽  
Cancer Therapies ◽  
Apoptosis Pathways

Background: Chronic myeloid leukemia (CML), is characterized by a reciprocal translocation t(9;22) and forms the BCR/ABL1 fusion gene, which is called the Philadelphia chromosome. The therapeutic targets for CML patients which are mediated with BCR/ABL1 oncogenic are tyrosine kinase inhibitors such as imatinib, dasatinib, and nilotinib. The latter two of which have been approved for the treatment of imatinib-resistant or intolerance CML patients. Mitotic catastrophe (MC) is one of the non-apoptotic mechanisms which frequently initiated in types of cancer cells in response to anti-cancer therapies; pharmacological inhibitors of G2 checkpoint members or genetic suppression of PLK1, PLK2, ATR, ATM, CHK1, and CHK2 can trigger DNA-damage-stimulated mitotic catastrophe. PLK1, AURKA/B anomalously expressed in CML cells, that phosphorylation and activation of PLK1 occur by AURKB at centromeres and kinetochores. Objective: The purpose of this study was to investigate the effect of dasatinib on the expression of genes in MC and apoptosis pathways in K562 cells. Methods: Total RNA was isolated from K-562 cells treated with the IC50 value of dasatinib and untreated cells as a control group. The expression of MC and apoptosis-related genes were analyzed by the qRT-PCR system. Results: The array-data demonstrated that dasatinib-treated K562 cells significantly caused the decrease of several genes (AURKA, AURKB, PLK, CHEK1, MYC, XPC, BCL2, and XRCC2). Conclusion: The evidence supply a basis to support clinical researches for the suppression of oncogenes such as PLKs with AURKs in the treatment of types of cancer especially chronic myeloid leukemia.

scholarly journals Apoptosis Induced by Tanshinone IIA and Cryptotanshinone Is Mediated by Distinct JAK/STAT3/5 and SHP1/2 Signaling in Chronic Myeloid Leukemia K562 Cells

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Ji Hoon Jung ◽  
Tae-Rin Kwon ◽  
Soo-Jin Jeong ◽  
Eun-Ok Kim ◽  
Eun Jung Sohn ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Biological Effects ◽  
K562 Cells ◽  
Tanshinone Iia ◽  
Anticancer Activities ◽  
Caspase 9 ◽  
Anticancer Effects ◽  
Induced Apoptosis ◽  
Better Than

Though tanshinone IIA and cryptotanshinone possess a variety of biological effects such as anti-inflammatory, antioxidative, antimetabolic, and anticancer effects, the precise molecular targets or pathways responsible for anticancer activities of tanshinone IIA and cryptotanshinone in chronic myeloid leukemia (CML) still remain unclear. In the present study, we investigated the effect of tanshinone IIA and cryptotanshinone on the Janus activated kinase (JAK)/signal transducer and activator of transcription (STAT) signaling during apoptotic process. We found that both tanshinone IIA and cryptotanshinone induced apoptosis by activation of caspase-9/3 and Sub-G1 accumulation in K562 cells. However, they have the distinct JAK/STAT pathway, in which tanshinone IIA inhibits JAK2/STAT5 signaling, whereas cryptotanshinone targets the JAK2/STAT3. In addition, tanshinone IIA enhanced the expression of both SHP-1 and -2, while cryptotanshinone regulated the expression of only SHP-1. Both tanshinone IIA and cryptotanshinone attenuated the expression of bcl-xL, survivin, and cyclin D1. Furthermore, tanshinone IIA augmented synergy with imatinib, a CML chemotherapeutic drug, better than cryptotanshinone in K562 cells. Overall, our findings suggest that the anticancer activity of tanshinone IIA and cryptotanshinone is mediated by the distinct the JAK/STAT3/5 and SHP1/2 signaling, and tanshinone IIA has the potential for combination therapy with imatinib in K562 CML cells.

scholarly journals Mechanisms of AXL overexpression and function in Imatinib-resistant chronic myeloid leukemia cells

Oncotarget ◽  
2011 ◽  
Vol 2 (11) ◽  
pp. 874-885 ◽  
Author(s):  
Maeva Dufies ◽  
Arnaud Jacquel ◽  
Nathalie Belhacene ◽  
Guillaume Robert ◽  
Thomas Cluzeau ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Leukemia Cells ◽  
Imatinib Resistant ◽  
And Function

scholarly journals Effects of Quercetin and Curcumin Combination on Signal Transduction Pathways in Chronic Myeloid Leukemia Cells

Proceedings ◽  
2018 ◽  
Vol 2 (25) ◽  
pp. 1524
Author(s):  
Ergul Mutlu Altundağ ◽  
Ayşe Mine Yılmaz ◽  
Belgin Sert ◽  
Tuğba Erkmen ◽  
Semra Koçtürk ◽  
...  
Keyword(s):  
Signal Transduction ◽  
Chronic Myeloid Leukemia ◽  
Signaling Pathways ◽  
Myeloid Leukemia ◽  
Synergistic Effects ◽  
K562 Cells ◽  
Leukemia Cells ◽  
Pcr Array ◽  
Normal Peripheral Blood ◽  
Synergistic Combination

Flavonoids have chemo-preventive and chemotherapeutic properties against different human cancers including chronic myeloid leukemia. Quercetin and curcumin are two polyphenols with potential anti-carcinogenic and pro-apoptotic properties. We have previously demonstrated the synergistic protective effect of quercetin and curcumin on chronic myeloid leukemia cells (K562) cells. Anti-proliferative and apoptotic effects of these polyphenols were examined by apoptosis and cell viability assays. Oxidative status of the cells was analyzed by determining the level of reactive oxygen species, mitochondrial permeability and intracellular glutathione. Obtained data showed that quercetin and curcumin had beneficial and synergistic effects on K562 cells. On the basis of the above-mentioned data, herein we aimed to clarify signaling pathways involved in synergistic combination of quercetin and curcumin on K562 cells. Normal peripheral blood mononuclear cell line was used as controls. The mRNA and protein expressions of the signaling pathways were detected by Human Signal Transduction Pathway Finder-RT2 PCR Array system and Western blotting, respectively. The results of PCR array were evaluated by DAVID v6.8 and database for KEGG pathways. Our data revealed that synergistic combination of curcumin quercetin was effective on genes that were particularly related to P53, NF and TGF. We believe that our findings will lead to new research in this area and will contribute to the chronic myeloid leukemia treatment protocols.

Molecular Mechanism Regulating Foxo In Leukemia Initiating Cells of Chronic Myeloid Leukemia.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3391-3391
Author(s):  
Kazuhito Naka ◽  
Takayuki Hoshii ◽  
Yuko Tadokoro ◽  
Takako Ooshio ◽  
Yukio Kondo ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Chronic Myeloid Leukemia ◽  
Nuclear Localization ◽  
Myeloid Leukemia ◽  
Cellular Localization ◽  
Molecular Mechanisms ◽  
Imatinib Treatment ◽  
Cytoplasmic Localization ◽  
Wild Type ◽  
Imatinib Resistant

Abstract Abstract 3391 Chronic myeloid leukemia (CML) is caused by a defined genetic abnormality that generates BCR-ABL, a constitutively active tyrosine kinase. Although the development of imatinib, a small molecule inhibitor of ABL, represents a breakthrough in the treatment of CML, major part of patients treated in chronic phase CML are not off therapy due to resistance or intolerance. Recent studies have suggested that imatinib is a potent inhibitor against differentiated leukemia cells, but does not deplete leukemia-initiating cells (LICs) responsible for recurrence of CML. To date, therapeutics that can eradicate CML LICs, however, have remained under investigation. To overcome these clinical problems, here we studied the molecular mechanisms regulating maintenance of imatinib-resistant CML LICs by forkhead transcription factor Foxo3a. We first generated a mouse CML model by using retroviral induction of BCR-ABL-ires-GFP gene into mouse immature hematopoietic cells, and the cells were subsequently transplanted into irradiated recipient mice. These experiments showed that CML LICs were highly enriched in c-Kit+Lin−Sca-1+ (KLS+) population in BCR-ABL+ CML cells. Serial transplantation experiments for CML LICs originated from Foxo3a-deficient mice and littermate wild-type mice indicated that Foxo3a-deficiency reduced lethality of recipient mice at third transplantation. Although recipients that transplanted with wild-type LICs developed CML and acute lymphocytic leukemia (ALL) at third transplantation, we did not observe development of ALL or CML in recipients of Foxo3a deficient LICs after 45 days post-third transplantation, suggesting that the Foxo3a deficient LICs lose their potential to generate malignancies. In addition, a combination of Foxo3a deficiency and imatinib treatment led to efficient depletion of CML in vivo, indicating that Foxo3a plays an essential role for the maintenance of imatinib-resistant CML LICs (Naka et al., Nature 463, 676–680, 2010). Interestingly, when we examined sub-cellular localization of Foxo3a transcription factor in the CML LICs, we found two CML LIC populations; one population was the cells with nuclear localization of Foxo3a (Foxo3a transcription factor is active) and the other population was the cells with cytoplasmic localization of Foxo3a (Foxo3a is inactive). To understand the molecular mechanisms regulating Foxo3a in CML LICs, we next evaluated the activity of upstream BCR-ABL, PI3K, PDK1, and Akt signaling pathway by fluorescence immunohistochemistry. BCR-ABL activity that was determined by phosphorylation levels of CrkL, a down-stream target of BCR-ABL, was detected in almost all of the CML LICs. However, unexpectedly, phosphorylation levels of Akt in the CML LICs with nuclear localization of Foxo3a appeared to be lower than that in the CML LICs with cytoplasmic localization of Foxo3a, despite it is widely believed that BCR-ABL induces activation of Akt signal. Consistent with Akt phosphorylation status, we detected low levels phosphorylation of PDK1 and PI3K p85, upstream regulators for Akt, in the CML LICs with nuclear localization of Foxo3a. Interestingly, expression levels of the cell proliferation antigen Ki67 were lower in the CML LICs with nuclear Foxo3a than that in the CML LICs with cytoplasmic Foxo3a. These results suggest that Foxo3a responsible for maintenance of imatinib-resistant CML LICs may be regulated by molecular mechanisms that are involved in dormancy in CML LICs. Disclosures: No relevant conflicts of interest to declare.

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