Nobiletin Promotes Megakaryocytic Differentiation through the MAPK/ERK-Dependent EGR1 Expression and Exerts Anti-Leukemic Effects in Human Chronic Myeloid Leukemia (CML) K562 Cells

Differentiation therapy is an alternative strategy used to induce the differentiation of blast cells toward mature cells and to inhibit tumor cell proliferation for cancer treatment. Nobiletin (NOB), a polymethoxyflavone phytochemical, is present abundantly in citrus peels and has been reported to possess anti-cancer activity. In this study, we investigated the anti-leukemic effects of NOB on cell differentiation and its underlying mechanisms in human chronic myeloid leukemia (CML) K562 cells. NOB (100 μM) treatment for 24 and 48 h significantly decreased viability of K562 cells to 54.4 ± 5.3% and 46.2 ± 9.9%, respectively. NOB (10–100 μM) significantly inhibited cell growth in K562 cells. Flow cytometry analysis and immunoblotting data showed that NOB (40 and 80 μM) could modulate the cell cycle regulators including p21, p27, and cyclin D2, and induce G1 phase arrest. NOB also increased the messenger RNA (mRNA) and protein expression of megakaryocytic differentiation markers, such as CD61, CD41, and CD42 as well as the formation of large cells with multi-lobulated nuclei in K562 cells. These results suggested that NOB facilitated K562 cells toward megakaryocytic differentiation. Furthermore, microarray analysis showed that expression of EGR1, a gene associated with promotion of megakaryocytic differentiation, was markedly elevated in NOB-treated K562 cells. The knockdown of EGR1 expression by small interference RNA (siRNA) could significantly attenuate NOB-mediated cell differentiation. We further elucidated that NOB induced EGR1 expression and CD61 expression through increases in MAPK/ERK phosphorylation in K562 cells. These results indicate that NOB promotes megakaryocytic differentiation through the MAPK/ERK pathway-dependent EGR1 expression in human CML cells. In addition, NOB when combined with imatinib could synergistically reduce the viability of K562 cells. Our findings suggest that NOB may serve as a beneficial anti-leukemic agent for differentiation therapy.

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Establishment of a novel mesenchymal stem cell-based regimen for chronic myeloid leukemia differentiation therapy

Cell Death and Disease ◽

10.1038/s41419-021-03499-w ◽

2021 ◽

Vol 12 (2) ◽

Author(s):

Shiman Zuo ◽

Luchen Sun ◽

Yuxin Wang ◽

Bing Chen ◽

Jingyue Wang ◽

...

Keyword(s):

Chronic Myeloid Leukemia ◽

Myeloid Leukemia ◽

Therapeutic Potential ◽

White Blood Cells ◽

Synergetic Effect ◽

Mapk Signaling ◽

Human Umbilical Cord ◽

Differentiation Therapy ◽

Hematopoietic Stem ◽

Megakaryocytic Differentiation

AbstractChronic myeloid leukemia (CML) is characterized by the accumulation of malignant and immature white blood cells which spread to the peripheral blood and other tissues/organs. Despite the fact that current tyrosine kinase inhibitors (TKIs) are capable of achieving the complete remission by reducing the tumor burden, severe adverse effects often occur in CML patients treated with TKIs. The differentiation therapy exhibits therapeutic potential to improve cure rates in leukemia, as evidenced by the striking success of all-trans-retinoic acid in acute promyelocytic leukemia treatment. However, there is still a lack of efficient differentiation therapy strategy in CML. Here we showed that MPL, which encodes the thrombopoietin receptor driving the development of hematopoietic stem/progenitor cells, decreased along with the progression of CML. We first elucidated that MPL signaling blockade impeded the megakaryocytic differentiation and contributed to the progression of CML. While allogeneic human umbilical cord-derived mesenchymal stem cells (UC-MSCs) treatment efficiently promoted megakaryocytic lineage differentiation of CML cells through restoring the MPL expression and activating MPL signaling. UC-MSCs in combination with eltrombopag, a non-peptide MPL agonist, further activated JAK/STAT and MAPK signaling pathways through MPL and exerted a synergetic effect on enhancing CML cell differentiation. The established combinational treatment not only markedly reduced the CML burden but also significantly eliminated CML cells in a xenograft CML model. We provided a new molecular insight of thrombopoietin (TPO) and MPL signaling in MSCs-mediated megakaryocytic differentiation of CML cells. Furthermore, a novel anti-CML treatment regimen that uses the combination of UC-MSCs and eltrombopag shows therapeutic potential to overcome the differentiation blockade in CML.

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Role of eIF3a in 4-amino-2-trifluoromethyl-phenyl retinate-induced cell differentiation in human chronic myeloid leukemia K562 cells

Gene ◽

10.1016/j.gene.2018.10.035 ◽

2019 ◽

Vol 683 ◽

pp. 195-209 ◽

Cited By ~ 4

Author(s):

Ge Li ◽

Ke Wang ◽

Yue Li ◽

Jinging Ruan ◽

Cong Wang ◽

...

Keyword(s):

Cell Differentiation ◽

Chronic Myeloid Leukemia ◽

Myeloid Leukemia ◽

K562 Cells

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VASP Protein, a Binding Partner Of BCR-ABL and FAK, May Be Implicated In The Chronic Myeloid Leukemia Phenotype

Blood ◽

10.1182/blood.v122.21.5162.5162 ◽

2013 ◽

Vol 122 (21) ◽

pp. 5162-5162

Author(s):

Vanessa Aline Bernusso ◽

João Agostinho Machado-Neto ◽

Fernando V Pericole ◽

Karla Priscila Vieira ◽

Adriana Silva Santos Duarte ◽

...

Keyword(s):

Bone Marrow ◽

Cell Adhesion ◽

Chronic Myeloid Leukemia ◽

Myeloid Leukemia ◽

K562 Cells ◽

Fold Increase ◽

Imatinib Treatment ◽

Gene Expressions ◽

Megakaryocytic Differentiation ◽

Healthy Donors

Abstract Background VASP (vasodilator-stimulated phosphoprotein) and Zyxin are actin regulatory proteins that control cell-cell adhesion. Zyxin directs actin assembly by interacting and recruiting VASP to specific sites of adhesion. The phosphorylation of VASP modifies their activity in cell-cell junctions. PKA phosphorylates VASP at serine 157 regulating VASP cellular functions. VASP is a substrate of BCR-ABL oncoprotein and is tyrosine-phosphorylated in leukemic cells. However, the function of VASP and Zyxin in hematopoietic cells, in the BCR-ABL pathway and its participation in chronic myeloid leukemia (CML) remains unknown. Aims To analyze VASP and Zyxin expression in bone marrow cells from CML patients and healthy donors, as well the involvement of these proteins in hematopoietic cell differentiation and in the BCR-ABL signaling pathway. Materials and Methods VASP and Zyxin expression and phosphorylation were studied in bone marrow samples from 29 individuals (5 healthy donors, 5 CML patients at diagnosis, 16 CML patients responsive to treatment with tyrosine kinase inhibitors (ITK) and 3 CML patients resistant to ITK). One patient was analyzed at diagnosis and after ITK response. VASP or Zyxin silencing was performed by shRNA-lentiviral delivery in K562 cell line, an appropriated shControl was used. ShControl, shVASP and shZyxin K562 cells were induced to megakaryocytic differentiation with 20nM of PMA (phorbol myristate -13 -12 acetate) during 4 days and CD61 expression, a marker for maturing megakaryocytes, was verified by flow cytometry. During megakaryocytic differentiation, VASP and Zyxin gene expressions were evaluated by quantitative PCR; protein expression and activation were determined by Western blotting. Effector proteins of proliferation, apoptosis and adhesion in the BCR-ABL signaling pathway were analyzed in cells silenced for VASP or Zyxin. The interaction of VASP and BCR-ABL or FAK was evaluated by co-immunoprecipiation. Results Healthy donors showed p-VASP ser157 expression, in contrast to CML patients at diagnosis who did not present phospho-VASP ser157. After Imatinib treatment CML patients restored VASP phosphorylation however resistant patients maintained this absence. Zyxin showed the same expression in patients and healthy donors. During Imatinib treatment of K562 cells, phospho-VASP ser157 expression was increased and its interaction with BCR-ABL protein was reduced. VASP and Zyxin gene expressions were upregulated during megakaryocyte differentiation of K562 cells (8.7-fold increase, P=0.0115, and 3.6-fold increase, P=0.015, respectively). VASP and Zyxin protein expressions were increased during megakaryocytic differentiation, including the active form of these proteins (p-VASP ser157 and p-Zyxin ser142). VASP silencing in K562 cells resulted in a 40% decrease of CD61 expression at the end of the megakaryocytic differentiation (P<0.05). In addition, VASP and Zyxin silencing resulted in a decrease of BCL-2 and BCL-XL proteins. VASP binds to FAK, an adhesion effector protein of the BCR-ABL pathway, and it´s silencing resulted in a decreased phosphorylation of FAK y925. Conclusions In BCR-ABL cells, VASP and Zyxin modulated anti-apoptotic proteins and megakaryocytic differentiation. Hence, the altered expression of VASP activity in CML patients may contribute to the pathogenesis of the disease, affecting cellular differentiation or leukemic cell adhesion. Disclosures: No relevant conflicts of interest to declare.

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CRKL but not CRKII Inhibits Erythropoiesis and Megakaryopoiesis of CML via Inactivating Raf/MEK/ERK/Elk-1 Pathway

10.21203/rs.3.rs-53960/v1 ◽

2020 ◽

Author(s):

Chunmei Guo ◽

Qiuling Zhang ◽

Jinsong Yan ◽

Xinxin Lv ◽

Frederick T Greenaway ◽

...

Keyword(s):

Chronic Myeloid Leukemia ◽

Myeloid Leukemia ◽

K562 Cells ◽

Erythroid Differentiation ◽

Underlying Mechanism ◽

Expression Level ◽

Differentiation Markers ◽

Expression Levels ◽

Qrt Pcr ◽

Megakaryocyte Differentiation

Abstract Background: As members of the CT10 regulation of kinase (CRK) adaptor protein family, CRK-like (CRKL) and CRKII are involved in cell proliferation, survival, adhesion, migration and differentiation. However, the exact role and underlying mechanism of CRKL and CRKII in leukemic cell differentiation are still unknown. Methods: Quantitative real-time qPCR (qRT-PCR) was used to detect the expression levels of CRKL and CRKII in chronic myeloid leukemia (CML) patients and complete remission (CR) patients; Western blotting (WB) was used to measure the expression levels of CRKL and CRKII during hemin-induced erythroid differentiation of K562 cells; Benzidine staining, isobaric tags for relative and absolute quantitation (iTRAQ) proteomic analysis, cDNA microarray assay, qRT-PCR and WB were used to examine the effects of CRKL and CRKII deregulation on erythroid and megakaryocyte differentiation of K562 cells; PD98059 was used to investigate the underlying mechanism of CRKL in erythropoiesis and megakaryopoiesis. Results: CRKL was found to be overexpressed in chronic myeloid leukemia (CML) patients compared with normal samples, while its expression level was lower in CR patients than in corresponding CML patients. The CRKL expression level was significantly decreased during the erythroid differentiation of K562 cells following hemin treatment. Moreover, CRKL downregulation promoted erythroid and megakaryocyte differentiation of K562 cells accompanied by increased expression level of the erythroid differentiation markers γ-globin, glycophorin (GPA) and the megakaryocyte differentiation markers CD41, CD61. Furthermore, gene microarray and iTRAQ quantitative proteomic analysis showed that CRKL downregulation increased hemoglobin (HB) molecules HBD, HBA1, HBA2, HBZ, HBE1, HBG1 and globin transcription factor 1 (GATA1), high-mobility group protein (HMGB2) expression levels. Mechanistically, CRKL inhibited erythroid and megakaryocyte differentiation of K562 cell via inactivating Raf/MEK/ERK/Elk-1 pathway. Conversely, CRKII was only slightly overexpressed in CML patients and had no effect on erythroid differentiation of K562 cells. Conclusions: Taken together, our results demonstrate that CRKL but not CRKII contributes to development, progression, erythropoiesis and megakaryopoiesis of CML, providing novel insights into effective diagnosis and therapy for CML patients.

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Role of Folate Receptor 3 in Tyrosine Kinase Inhibitor Discontinuation in Chronic Myeloid Leukemia

Blood ◽

10.1182/blood-2018-99-111611 ◽

2018 ◽

Vol 132 (Supplement 1) ◽

pp. 2998-2998

Author(s):

Na Shen ◽

Xiaojian Zhu ◽

Shu Zhou ◽

Yong You ◽

Zhaodong Zhong ◽

...

Keyword(s):

Cell Cycle ◽

Bone Marrow ◽

Cell Differentiation ◽

Chronic Myeloid Leukemia ◽

Tumor Cell ◽

Transcriptome Analysis ◽

Myeloid Leukemia ◽

Folate Receptor ◽

K562 Cells ◽

Tumor Cell Differentiation

Abstract Chronic myeloid leukemia (CML) is a clonal myeloproliferative disorder characterized by Philadelphia chromosome and its molecular counterpart, the BCR-ABL1 fusion gene. Discontinuation of tyrosine kinase inhibitors (TKIs) therapy after achieving a persistent deep molecular response (DMR) is an urgently-needed treatment goal for patients and it was written in NCCN guideline Version 2.2017 for CML. Indeed, various studies have confirmed the feasibility of stopping TKIs therapy in many regions. However, increasing evidence demonstrated that TKIs are unable to eliminate quiescent leukemic stem cells (LSCs), which lead to treatment resistance or relapse after discontinuation of TKIs treatment. Multiple works have confirmed that approximately 50-60% of DMR patients stopping TKIs will lose their response and require retreatment. The patients who will lose the treatment-free remission (TFR) remains unknown currently. We selected bone marrow of 14 patients (matched 7 relapse and 7 non-relapse patients) who discontinued TKIs therapy in our center for transcriptome analysis to discover the differences between relapse and non-relapse patients. Bioinformatics indicated that folate receptor 3 (FOLR3) was highly expressed in non-relapse patients and only in the non-relapsers (Figure 1A). Further work found these samples all carried a common SNP mutation. Then we respectively transferred newly diagnosed chronic phase (CP) CML patients derived bone marrow CD34+ cells and CML K562 cells with lentiviral vectors containing FOLR3 SNP, FOLR3 SNP shRNA, and wild type FOLR3. The result indicated that FOLR3 SNP significantly promoted the clonogenicity of CD34+/K562 cells, while loss of FOLR3 SNP hindered cell differentiation (Figure 1B and D are data of CD34, Figure 1C and E are data of K562). K562 subcutaneous tumor formation in balb/c node mice confirmed that tumors weight and volume of FOLR3 SNP shRNA group were higher than control. While, small animal PET scanning showed that maximum standardized uptake value (SUVmax) of 18F-FDG of FOLR3 SNP+ group was higher than the rest. Experiments in vivo and vitro synergistically proved FOLR3 SNP promoted tumor cell differentiation, delayed tumor growth. To better understand how FOLR3 SNP promote tumor cell differentiation and delay tumor growth, we performed second transcriptome analysis. Consistently, both in FOLR3 SNP+ CD34+ and K562 cells, enrichment analysis revealed that differentially expressed genes were enriched in mitochondria associated Gene Ontology (GO) biological process (Figure F), in which mitochondria complex V matched genes were most significant, such as ATP5 family. In vitro, we demonstrated that ATP syntheses, maximal respiration and spare respiratory capacity of FOLR3 SNP+ CD34+/K562 cells were significantly higher than control and shFOLR3 counterpart through seahorse XF cell mito stress test (Figure G and H refer to CD34 and K562, separately). Electron microscope also exhibited an increase of mitochondrial in FOLR3 SNP+ cells. Mitochondria play an essential role in energy generation, cell signalling, differentiation, death and senescence in eukaryotic cells. We detected a series of genes related to aging, cell cycle and mitochondria unfolded protein response. The results showed that cell cycle kinase such as CDK4 decreased in FOLR3 SNP+ CD34+/K562 cells. On the other hand, senescence associated genes seemed increased. In conclusion, we highlighted the connection of FOLR3 and post-cessation relapse. FOLR3 SNP could be an indicator of TFR. Its internal mechanism might be the mitochondrion activation induced aging of residual leukemia cells. Figure. Figure. Disclosures No relevant conflicts of interest to declare.

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FLT3 Is Up-Regulated in Blast Crisis of Chronic Myeloid Leukemia and Combination of Small Interference RNA of FLT3 and Gleevec (STI571) Synergistically Induces the Apoptosis in K562 Cells.

Blood ◽

10.1182/blood.v110.11.4532.4532 ◽

2007 ◽

Vol 110 (11) ◽

pp. 4532-4532

Author(s):

Young Y. Lee ◽

Kwang-Sung Ahn ◽

Sung-Soo Yoon ◽

Jung H. Choi ◽

Byoung B. Park ◽

...

Keyword(s):

Chronic Myeloid Leukemia ◽

Myeloid Leukemia ◽

Blast Crisis ◽

Chronic Phase ◽

K562 Cells ◽

Pcr Analysis ◽

Wild Type ◽

Small Interference Rna ◽

Expression Levels ◽

Significant Difference

Abstract To identify a gene signature for prognostic markers at transition from chronic phase to blast crisis of chronic myeloid leukemia (CML), we have applied Affymetrix Genechips of 22,000 transcripts to analyze total RNA of CML cells from 12 patients with chronic phase and 12 patients with blast crisis. Data analysis using GeneSpring 6.0 generated a list of 143 differentially expressed genes. A total of 89 genes were up-regulated and 54 genes were down-regulated in blast crisis of CML, and vice versa in chronic phase of CML. Array data for 32 genes was validated using quantitative realtime PCR analysis. The expression levels of HSA6591, FLT3, NTE5, RSG1, LAF4, CPA3, ATF, FCGR3A, MYD88, IFIT1, TP73L, DTNA, MDA, and IL18R1 showed statistically significant difference (p < 0.05) between chronic phase and blast crisis. Since CML cells of blast crisis were generally unresponsive to STI571, we further analyzed roles of FLT3 which is known to be a poor prognositic marker in acute myeloid leukemia. For this experiment, K562 cells (CML blast cells) were transfected with small hairpin RNAs (shRNAs), also referred to as small interfering RNAs, to target human FLT3, resulting in the significant inhibition of FLT3 expression at mRNA and protein levels. MTT assay demonstrated that FLT3 knockdown K562 cells by shRNAs were more sensitive to STI571 compared to wild type of K562, although there was no difference at high concentration of STI571 (320 nM) between FLT3 knockdown K562 cells and wild type of K562 cells. The higher expression levels of apoptosis related genes (PARP, caspase-3, Bax) were observed in FLT3 knockdown K562 cells compared to wild type of K562 cells. Thus, RNA interference-directed targeting of FLT3 might be a novel treatment modality in STI571 refractory CML patients.

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

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520620666201106085929 ◽

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.

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EXPRESS: Characterization of Drug Resistance in Chronic Myeloid Leukemia Cells Based on Laser Tweezers Raman Spectroscopy

Applied Spectroscopy ◽

10.1177/00037028211024581 ◽

2021 ◽

pp. 000370282110245

Author(s):

Qian Zhang ◽

Minlu Ye ◽

Lingyan Wang ◽

Dongmei Jiang ◽

Shuting Yao ◽

...

Keyword(s):

Raman Spectroscopy ◽

Chronic Myeloid Leukemia ◽

Myeloid Leukemia ◽

K562 Cells ◽

Laser Tweezers ◽

Label Free ◽

Multivariate Statistical ◽

Analytical Strategy ◽

Specificity And Sensitivity ◽

Acid Protein

Multidrug resistance (MDR) is highly associated with poor prognosis of chronic myeloid leukemia (CML). This work aims to explore whether the laser tweezers Raman spectroscopy (LTRS) could be practical in separating adriamycin (ADR) resistance CML cells K562/ADR from its parental cells K562, and to explore the potential mechanisms. Detection of LTRS initially reflected the spectral differences caused by chemoresistance including bands assigned to carbohydrates, amino acid, protein, lipids and nucleic acid. In addition, principal components analysis (PCA) as well as the classification and regression trees (CRT) algorithms showed that the specificity and sensitivity were above 90%. Moreover, the band data-based CRT model and receiver operating characteristic (ROC) curve further determined some important bands and band intensity ratios to be reliable indexes in discriminating K562 chemoresistance status. Finally, we highlighted three metabolism pathways correlated with chemoresistance. This work demonstrates that the label-free LTRS analysis combined with multivariate statistical analyses have great potential to be a novel analytical strategy at the single-cell level for rapid evaluation the chemoresistance status of K562 cells.

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Secondary Structural Model of MALAT1 Becomes Unstructured in Chronic Myeloid Leukemia and Undergoes Structural Rearrangement in Cervical Cancer

Non-Coding RNA ◽

10.3390/ncrna7010006 ◽

2021 ◽

Vol 7 (1) ◽

pp. 6

Author(s):

Matthew C. Wang ◽

Phillip J. McCown ◽

Grace E. Schiefelbein ◽

Jessica A. Brown

Keyword(s):

Cervical Cancer ◽

Chronic Myeloid Leukemia ◽

Hela Cells ◽

Binding Sites ◽

Myeloid Leukemia ◽

Structural Changes ◽

Structural Model ◽

Dimethyl Sulfate ◽

K562 Cells ◽

Cancer Types

Long noncoding RNAs (lncRNAs) influence cellular function through binding events that often depend on the lncRNA secondary structure. One such lncRNA, metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), is upregulated in many cancer types and has a myriad of protein- and miRNA-binding sites. Recently, a secondary structural model of MALAT1 in noncancerous cells was proposed to form 194 hairpins and 13 pseudoknots. That study postulated that, in cancer cells, the MALAT1 structure likely varies, thereby influencing cancer progression. This work analyzes how that structural model is expected to change in K562 cells, which originated from a patient with chronic myeloid leukemia (CML), and in HeLa cells, which originated from a patient with cervical cancer. Dimethyl sulfate-sequencing (DMS-Seq) data from K562 cells and psoralen analysis of RNA interactions and structure (PARIS) data from HeLa cells were compared to the working structural model of MALAT1 in noncancerous cells to identify sites that likely undergo structural alterations. MALAT1 in K562 cells is predicted to become more unstructured, with almost 60% of examined hairpins in noncancerous cells losing at least half of their base pairings. Conversely, MALAT1 in HeLa cells is predicted to largely maintain its structure, undergoing 18 novel structural rearrangements. Moreover, 50 validated miRNA-binding sites are affected by putative secondary structural changes in both cancer types, such as miR-217 in K562 cells and miR-20a in HeLa cells. Structural changes unique to K562 cells and HeLa cells provide new mechanistic leads into how the structure of MALAT1 may mediate cancer in a cell-type specific manner.

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

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2013/805639 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 19

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.

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