scholarly journals Novel Mechanism by a Bis-Pyridinium Fullerene Derivative to Induce Apoptosis by Enhancing the MEK-ERK Pathway in a Reactive Oxygen Species-Independent Manner in BCR-ABL-Positive Chronic Myeloid Leukemia-Derived K562 Cells

2022 ◽  
Vol 23 (2) ◽  
pp. 749
Author(s):  
Kazuya Sumi ◽  
Kenji Tago ◽  
Yosuke Nakazawa ◽  
Kyoko Takahashi ◽  
Tomoyuki Ohe ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
K562 Cells ◽  
Fullerene Derivative ◽  
Erk Pathway ◽  
Oxygen Species ◽  
Independent Manner ◽  
Extracellular Signal Regulated Kinase ◽  
Extracellular Signal ◽  
Induced Apoptosis

In the treatment of breakpoint cluster region-Abelson (BCR-ABL)-positive chronic myeloid leukemia (CML) using BCR-ABL inhibitors, the appearance of a gatekeeper mutation (T315I) in BCR-ABL is a serious issue. Therefore, the development of novel drugs that overcome acquired resistance to BCR-ABL inhibitors by CML cells is required. We previously demonstrated that a bis-pyridinium fullerene derivative (BPF) induced apoptosis in human chronic myeloid leukemia (CML)-derived K562 cells partially through the generation of reactive oxygen species (ROS). We herein show that BPF enhanced the activation of the mitogen-activated protein kinase/extracellular signal-regulated kinase kinase-extracellular signal-regulated kinase (MEK-ERK) pathway in a ROS-independent manner. BPF-induced apoptosis was attenuated by trametinib, suggesting the functional involvement of the MEK-ERK pathway in apoptosis in K562 cells. In addition, the constitutive activation of the MEK-ERK pathway by the enforced expression of the BRAFV600E mutant significantly increased the sensitivity of K562 cells to BPF. These results confirmed for the first time that BPF induces apoptosis in K562 cells through dual pathways—ROS production and the activation of the MEK-ERK pathway. Furthermore, BPF induced cell death in transformed Ba/F3 cells expressing not only BCR-ABL but also T315I mutant through the activation of the MEK-ERK pathway. These results indicate that BPF is as an effective CML drug that overcomes resistance to BCR-ABL inhibitors.

Extracellular Signal-Regulated Protein Kinase 5 Mediates Resistance of Human Chronic Myeloid Leukemia K562 Cells to Imatinib.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2131-2131
Author(s):  
Mikhail A. Sovershaev ◽  
Elena M. Egorina ◽  
Franz X. Gruber ◽  
Geir Bjørkøy ◽  
Terje Johansen
Keyword(s):  
Cell Cycle ◽  
Chronic Myeloid Leukemia ◽  
Cell Survival ◽  
Myeloid Leukemia ◽  
K562 Cells ◽  
Kinase Domain ◽  
Imatinib Treatment ◽  
Wild Type ◽  
Extracellular Signal ◽  
Induced Apoptosis

Abstract Mutations in the Abl kinase domain and Bcr-Abl gene amplification have been recognised as the most common mechanisms of resistance to Imatinib (Gleevec) in chronic myeloid leukemia (CML). However, Imatinib resistance by Bcr-Abl independent mechanisms have also been reported. The extracellular signal-regulated protein kinase 5 (Erk5) signalling pathway is involved in cell survival and cell cycle control functions. Interestingly, it was recently reported that ERK5 is important in CML (Buschbeck M., 2005). Bcr/Abl was found to increase the level of Erk5 by stabilizing the protein thus contributing to increased cell survival. In this study we asked whether small interfering RNA (siRNA)-mediated depletion of endogenous Erk5 or overexpression of wild type Erk5 would affect the survival of Imatinib-treated human K562 CML cells. These cells express Bcr-Abl with a wild type kinase domain. Fluorescence activated cell sorting analyses of propidium iodide-stained K562 cells revealed that treatment with 1 μM Imatinib for 24 hrs led to an increase of the apoptotic cell population from 9 to 27 %. The number of cells, arrested in G0/1 phase was also elevated following Imatinib treatment from 66 to 85 %. Overexpression of wild type Erk5 in K562 cells reduced the frequency of Imatinib-induced apoptosis from 27 to 18 % without affecting cell cycle distribution of the living cells. After having established that overexpression of Erk5 renders cells partially resistant to Imatinib treatment we tested the effect of siRNA-mediated depletion of endogenous Erk5 on the viability of K562 cells challenged with Imatinib. Indeed, 42% of K562 cells transfected with siRNA against Erk5 underwent apoptosis after Imatinib treatment. Imatinib induced apoptosis in only 20% of cells transfected with a control siRNA. Furthermore, Erk5 depletion strongly inhibited cell cycle progression in Imatinib-treated K562 cells. Thus, the cell populations in S phase and mitosis were reduced from 22 to 16 % and from 24 to 9 %, respectively. Taken together, our data and those of Buschbeck et al. suggest that ERK5 levels may strongly affect cell survival during Imatinib treatment of CML cells.

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.

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.

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.

scholarly journals 5-Hydroxytryptamine4 Receptor Activation of the Extracellular Signal-regulated Kinase Pathway Depends on Src Activation but Not on G Protein or β-Arrestin Signaling

2007 ◽  
Vol 18 (6) ◽  
pp. 1979-1991 ◽  
Author(s):  
Gaël Barthet ◽  
Bérénice Framery ◽  
Florence Gaven ◽  
Lucie Pellissier ◽  
Eric Reiter ◽  
...  
Keyword(s):  
Receptor Activation ◽  
Erk Pathway ◽  
Independent Manner ◽  
Src Tyrosine Kinase ◽  
Erk Activation ◽  
Extracellular Signal Regulated Kinase ◽  
Transient Activation ◽  
293 Cells ◽  
Extracellular Signal ◽  
Kinase Pathway

The 5-hydroxytryptamine4 (5-HT4) receptors have recently emerged as key modulators of learning, memory, and cognitive processes. In neurons, 5-hydroxytryptamine4 receptors (5-HT4Rs) activate cAMP production and protein kinase A (PKA); however, nothing is known about their ability to activate another key signaling pathway involved in learning and memory: the extracellular signal-regulated kinase (ERK) pathway. Here, we show that 5-HT4R stimulation, in primary neurons, produced a potent but transient activation of the ERK pathway. Surprisingly, this activation was mostly PKA independent. Similarly, using pharmacological, genetic, and molecular tools, we observed that 5-HT4Rs in human embryonic kidney 293 cells, activated the ERK pathway in a Gs/cAMP/PKA-independent manner. We also demonstrated that other classical G proteins (Gq/Gi/Go) and associated downstream messengers were not implicated in the 5-HT4R–activated ERK pathway. The 5-HT4R–mediated ERK activation seemed to be dependent on Src tyrosine kinase and yet totally independent of β-arrestin. Immunocytofluorescence revealed that ERK activation by 5-HT4R was restrained to the plasma membrane, whereas p-Src colocalized with the receptor and carried on even after endocytosis. This phenomenon may result from a tight interaction between 5-HT4R and p-Src detected by coimmunoprecipitation. Finally, we confirmed that the main route by which 5-HT4Rs activate ERKs in neurons was Src dependent. Thus, in addition to classical cAMP/PKA signaling pathways, 5-HT4Rs may use ERK pathways to control memory process.

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