bluuebunny/crossref_metadata_2025_split huggingface dataset:
Screening and Identifying of the Protein Tyrosine Phosphatase Superfamily Members Related to Chronic Myeloid Leukemia and Exploration of Its Potential Function.
Authors: Du Qingfeng , Zhang Song , Li Rong , Gong Junmei , Zhu Hongqian , Wang Yu , Yao Feng , Fan Wei , Liu Xiaoli , Zhou Shuyu 
Published: April 2020

Abstract
Chronic myeloid leukemia (CML) is characterized by formation of a BCR-ABL fusion gene, which encodes a chimeric protein, P210BCR-ABL. The protein tyrosine kinase(PTK) activity of P210BCR-ABL is aberrantly regulated and lead to catalyzes the phosphorylation of tyrosine residues in specific sites of P210BCR-ABL itself and a host of substrates, which is considered as the sufficient and necessary factor in the pathogenesis of CML. Current studies suggest that the tyrosine phosphorylation is a reversible dynamic procedure which is governed by the coordinated and competing actions of PTK and protein tyrosine phosphatases(PTP). As the balance between PTK and PTP are broken by P210BCR-ABL in CML, we assume that some responsive regulations must been done by the cells in order to antagonize the impact of PTK activity of P210BCR-ABL. Among those regulations, the changes at the transcriptional level of many important genes including PTP will be most direct and efficient. In order to screen and identify PTP related to CML and explore its potential function, we firstly induced apoptosis of K562 cells with STI571 and analyze the differential expression of PTP with BioStarH40s expression profile cDNA array. Among the 21 PTP included in the BioStarH40s cDNA microarray, 2 PTP, FAP1(NM_006264, ration=2.417) and SHP1(M77273, ration=5.012) showed differential expression. The results of cDNA microarray confirmed by semi-quantitative RT-PCR suggested that FAP1and SHP1 may involve the apoptotic signal transduction pathway triggered by STI571. Secondly, the mRNA level of SHP1 in CML was analyzed with semi-quantitative RT-PCR. The results detected that the mRNA expression level of SHP1 in CML-CP (7 cases) show no statistic difference with normal control. But in contrast, the mRNA expression had down-regulated in CML-BC(4 cases) and show significant difference with normal control. Furthermore, we cloned the full length cDNA sequence of SHP1 with RT-PCR and sub-cloned it into the mammalian expression vector pcDNA3.0. The orientation and the sequence of pcDNA3-SHP1 were further validated by restrictive enzyme digestion analysis and DNA sequence analysis. Thirdly, the potential functions of the SHP1, such as triggering apoptosis and inducing differentiation, were explored by over-expressing the candidate gene in K562 cells with lipofectin transfection technique. The results showed that over-expression of SHP1 in K562 cells is sufficient for inducing apoptosis and erythroid differentiation that may be strengthened by the additional of STI571 treatment.
Characterization of the NAD-Dependent Human Histone Deacetylases Gene Sirtuin 1 and Its Implications on Aging and the Development of Malignant Disease.
Authors: Mahlknecht Ulrich R. , Voelter-Mahlknecht Susanne F. 
Published: April 2020

Abstract
A dysregulation of the tightly controlled equilibrium of acetylation and deacetylation plays a causative role in the generation as well as in the suppression of cancer. Histone acetylation modifiers are therefore gaining increasing attention as potential targets in the treatment of cancer. Sirtuin 1 (SIRT1) is a nicotinamide adenine dinucleotide (NAD+)-dependent deacetylase, which belongs to the silent information regulator 2 (Sir2) family of sirtuin histone deacetylases (HDACs). The yeast Sir2 protein and its mammalian derivatives play a central role in epigenetic gene silencing, DNA repair and recombination, cell-cycle, microtubule organization, and in the regulation of aging. We have isolated and characterized the human Sirt1 genomic sequence and identified a number of SIRT1 protein interaction partners, which will be important for the further understanding its physiological role. The Sirt1 gene spans a region of 33,660 bp and is located on chromosome 10q21.3. The protein is localized in the nucleus, and interacts with and deacetylates a growing number of proteins, such as p53, the Forkhead transcription factor FOXO3A, PML, BCL6, TAFI68, HES1, and CTIP2. SIRT1 has been shown to be essential for embryonic development, muscle differentiation and is an important mediator of organismal longevity through a number of different mechanisms such as the induction of cell cycle arrest, resistance to oxidative stress and the inhibition of apoptosis.
Some histone deacetylase genes have been shown to be rearranged in the context of chromosomal translocations in human acute leukemias and solid tumors, where fusions of regulatory and coding regions of a variety of transcription factor genes result in completely new gene products, which may interfere with regulatory cascades that control cell growth and differentiation. On the other hand, some histone acetylation modifying enzymes have been located within chromosomal regions that are particularly prone to chromosomal breaks. In these cases gains and losses of chromosomal material may affect the availability of functionally active HATs and HDACs, which in turn disturbs the tightly controlled equilibrium of histone acetylation. A deletion of Sirt1 would therefore most probably shift the steady state toward acetylation at the level of specific genes targeted by SIRT1 and either upregulate or downregulate transcriptional events. Such dysregulation might represent a critical event in the multistep pathway leading to full cellular transformation and the development of malignancy.
Protein Interaction Partners of PDZ-Binding Kinase (PBK) Implicate a Possible Role in Leukemogenesis.
Authors: Nandi Asit K. , Ford Tamara , Fleksher Daniel , Neuman Brian , Rapoport Aaron P. 
Published: April 2020

Abstract
Considering the fact that multiple genetic hits are required for the development of human cancers, we focused to examine the possible complementation by a novel mitotic kinase called PDZ- binding kinase (PBK) in the backdrop of deregulated c-Myc expression which either as a primary or a secondary genetic event is responsible for a wide variety of cancers including hematological malignancies. PBK, a mitotic kinase and a MAP kinase kinase homolog was originally identified in the laboratory as a differentially expressed gene in Burkitt’s lymphoma cell line GA10 compared to hyperplastic tonsillar B cells. We earlier found that PBK was upregulated in 9 out of 12 primary samples of acute myelogenous leukemia (AML) as well as several other leukemia and lymphomas while CD34+ immunoselected bone marrow stem/ progenitor cells expressed very little PBK. PBK was found to be coregulated with c-Myc during macrophage differentiation of promyelocytic leukemia cells HL60 and during growth arrest in the presence of low doses of an antineoplastic compound doxorubicin. We further demonstrated that binding by the cell cycle- specific transcription factors E2F and CREB/ ATF respectively at −146 bp and −312 bp positions upstream of the transcription start site of PBK is required for optimal PBK expression. In order to understand the functional implications of PBK expression in oncogenically stimulated cells, we have analyzed the protein- protein interactions involving PBK in the human bone marrow cells utilizing yeast two- hybrid approach. To this end, a constitutively active PBK mutant was expressed in yeast as a fusion protein with GAL4 DNA- binding domain. Utilizing GAL4- PBK as bait, we have isolated several cDNA clones including those encoding the high- mobility group nucleosomal binding protein 2 (HMGN2) and ret finger protein 2 (RFP2) as potential interaction partners for PBK. It was reported that mitotic phosphorylation of the nucleosomal binding domain (NBD) present in the HMGN1, another member of the related protein family, regulates interaction with 14.3.3 proteins and entry into the nuclei. In a separate study, it was reported that a 31 amino acid synthetic peptide from HMGN2 overlapping to NBD when injected intravenously was able to direct homing to the nuclei of tumor cells. RFP2 is a candidate tumor suppressor gene residing in the critical deleted region (CDR) 13q14 as it occurs in several different hematological malignancies such as B-cell chronic lymphocytic leukemia (CLL), mantle cell lymphoma, diffuse large cell lymphoma, myeloma including solid tumors such as head and neck cancer, oral tumors and prostate carcinoma. Validation of these interactions in the mammalian cell environment is currently in progress.
Tetraspanins Affect Myeloma Cell Fate Via Akt Signaling and FoxO Activation.
Authors: Drucker Liat , Zismanov Victoria , Tohami Tali , Tartakover-Matalon Shelly , Lishner Michael 
Published: April 2020

Abstract
The significance of cellular interaction with microenvironmental components to tumor progression is increasingly acknowledged. In myeloma (MM), the involvement of bone marrow is critically important to cell growth, survival and drug resistance. It is currently perceived that effective disease treatment must address these interactions. We have previously shown that re-expression of the eGFP fusion proteins CD81-N1 and CD82-N1 tetraspanins in MM cell lines (CAG, RPMI 8226) caused cell stress and massive death. Here we demonstrate that the anti-myeloma effect of CD81-N1 and CD82-N1 compared to mock involves: a down-regulation of Akt(Ser473) [20%–40%]; activation of FoxO transcription factors [evidenced in decreased phosphorylation (20%–40%) and elevated transcription of Gadd45A (70%–80%)]; and is accompanied by a decrease in phosphorylated mTOR(Ser2448) [30%] and mTOR/rictor activity [demonstrated in phosphorylation of Akt at Ser473 position] (p&lt;0.05). Next, we investigated the involvement of PI3K, the prime activator of Akt. Our results show that addition of the PI3K inhibitor wortmannin, affected both the mock and tetraspanin transfected myeloma cells in the same manner. We deduce from these results that the CD81-N1/CD82-N1 induced death is independent of the PI3K signaling. This finding further supports the importance of mTOR/rictor rather than PI3K in the regulation of Akt activity under these circumstances. Based on publications that attribute JNK a regulatory role in FoxO4 activity, especially in stress related scenarios, we decided to examine the consequences of JNK inhibition on tetraspanin induced cell death. Indeed, a most significant rescue of 26% of the cells was demonstrated in the CD81-N1 transfected CAG. Moreover, we conjectured that the cell death was due to myeloma dependence on Akt activation. Hence, in a breast cancer cell line model characterized with variegated levels of Akt activation we demonstrated that the tetraspanin effect was also mediated via Akt and dependent on the ‘cell’s addiction’ to its activity. Significantly higher rates of cell death were observed in the Akt dependent MDA-MB-231 breast cancer cell line compared to Akt independent MCF-7 with both CD81-N1 and CD82-N1 overexpression (70% versus 50% and 50% versus 10%, respectively). Moreover, in CD82-N1 transfected MDA-MB-231 we observed a significant reduction in Akt(Ser473). We suggest that tetraspanins have modulator potential in MM and constitute a promising frontier to be explored in Akt dependent pathological conditions. Moreover, targeting the pathways (via the ‘tetraspanin switch’) rather than blocking a single factor may present a promising therapeutic strategy in a complex drug resistant disease such as myeloma.
Delayed Achievement of Molecular Responses Is Associated with Increased Risk of Progression among Patients (pts) with Chronic Myelogenous Leukemia (CML) In Chronic Phase (CP) Treated with Imatinib (IM).
Authors: Quintas-Cardama Alfonso , Kantarjian Hagop M. , Jones Dan , Garcia-Manero Guillermo , O’Brien Susan , Shan Jenny , Ravandi Farhad , Wierda William G. , Cortes Jorge 
Published: April 2020

Abstract
Background: Achieving a cytogenetic (CG) response or a molecular response after imatinib therapy has been associated with improved event-free (EFS) and transformation-free survival (TFS). It is unclear whether achieving these responses earlier confers an advantage. A recent update of the IRIS trial suggests that achieving a major CG response (MCyR) at 12, 18 or 24 months (mo) confers a similar TFS advantage. Another report (J Clin Oncol2006;24:454) suggests that achieving a complete CG response (CCyR) at 12 or 24 mo confers equal prognosis to patients. Although some patients may indeed improve their response with continued therapy, a pt not in CCyR faces the competing possibilities of eventually achieving a CCyR vs progressing.
Methods: We analyzed the risks of improving the CG response vs progressing for pts not in CCyR at different times to determine whether early responses confer an advantage. 258 pts with CML CP treated with IM were analyzed. Progression was defined as transformation to AP or BP, loss of CHR or major CG response, or a doubling of the white cell count to more than 20x109/L.
Results: After 3 mo of IM therapy, 77 (74%) of 104 assessable pts for CG response had a CCyR whereas 17 (16%) progressed. These differences were consistently significant at 6 and 12 mo (p=0.04) (Table 1).
We then analyzed the long term risk of progression vs the probability of achieving CCyR according to the molecular response at different time points (Table 2).
Patients with Bcr-Abl/Abl transcript levels &gt;1–10 after 3 mo of therapy had a 92% probability of achieving CCyR with continued therapy, similar to the 98% for those with ≤1. However, they have a significantly higher risk of eventual progression that is more similar to that of pts with values of &gt;10. The risk of progression increases to 23% if transcript levels &gt;10 at 6 mo.
Conclusion: These results suggest that while the risk of progression may be similar for pts who achieve a CCyR regardless of the time at which that is attained, those who fail to obtain a CCyR within the first 12 mo of IM therapy have higher rates of disease progression. This risk is discernible as early as 3 mo into IM therapy and may provide a rationale for therapies that induce higher rates of early molecular response (e.g. high-dose imatinib, new tyrosine kinase inhibitors).
Table 1 Time on imatinib No. not in CCyR No. with eventual outcome with continued therapy (%) CCyR Progression p value 3 months 104 77 (74) 17 (16) 6 months 47 28 (60) 12 (26) 0.04 12 months 26 16 (62) 8 (31)
Table 2 % Probability Months %Bcr-Abl/Abl No. CCyR Progression p value ≤ 1 87 98 2 3 &gt; 1–10 76 92 11 0.04 &gt; 10 30 67 13 ≤ 1 140 99 4 6 &gt; 1–10 34 91 9 0.005 &gt; 10 13 62 23
The Study of Effect and Mechanism by Vitamin K2 on Human MDS Cell Line MUTZ-1.
Authors: Chen Bao-An , Xu Xin , Shao Ze-Ye , Ding Jia-Hua , Xia Guo-Hua , Gao Chong , Sun Yun-Yu , Chen Ning-Na , Fei Fei 
Published: April 2020

Abstract
The myelodysplastic syndromes (MDS) are characterized by hemopoietic insufficiency associated with cytopenias leading to serious morbidity and the additional risk of leukemic transformation. Vitamin K2(VK2) is reported to induce apoptosis or differentiation of leukemic cell lines in vitro. For investigating the effects and mechanism of VK2 on human MDS cell line MUTZ-1 in vitro,we observed the changes of morphologic features of MUTZ-1 cells by exposing to VK2.The transmission electron microscope was used to observe the apoptosis of MUTZ-1 cells. Cellular proliferation was determined by the MTT assay. The flow cytometry was used to analysis apoptosis rate and the change of cell cycle. The expression of apoposis-related genes bcl-2, survivin and bax were detected by reverse transcriptase polymerase chain reaction(RT-PCR).The activity of caspase-3 was detected by chemiluminescence assay. After exposing to 10μmol L−1 and higher concentration of VK2, it could inhibit MUTZ-1 cells proliferation in a dose-and time-dependent manner(p&lt;0.05). At concentration of 5μmol/l VK2 treatment, it might accelerate cellular proliferation, but there’s no significant difference compared with control group. Apoptosis peak on FCM and positive Annexin-V FITC/PI on cell membrane showed that VK2 induced apoptosis of MUTZ-1 cells in a dose-and-time-dependent manner, G0/G1 cell cycle arrest, significantly dow-regulated the expression of bcl-2 and survivin, but had no effect on the expression of bax.The activities of caspase-3 were significantly increased. Low concentration of VK2 could facilitate cell proliferation. The higher concentration of VK2 could induce apoptosis of MUTZ-1 cells. These results indicate that VK2 induces MUTZ-1 cells apoptosis by activating caspase-3 pathway, the apoptosis related genes bcl-2, survivin down-regulated might play an important role in this process.
Prognostic Significance of Multidrug Resistance Proteins Expression in Acute Myeloid Leukemia.
Authors: Zakharov Oleg D. , Rybalkina Ekaterina U. , Stavrovskaya Alla A. , Volkova Maya 
Published: April 2020

Abstract
Background: Conventional induction chemotherapy induces complete remission (CR) in 65–75% of adults with de novo acute myeloid leukemia (AML), and 15–20% of the patients have refractory disease. We investigated the prognostic significance of multidrug resistance proteins (P-glycoprotein (Pgp), BCRP, MRP1 and LRP) expression on AML blast cells before treatment.
Methods: We included in analysis 30 patients (pts) with de novo AML. Expression of multidrug resistance proteins (MDR) was detected by indirect immunofluorescence technique and flow cytometry on bone marrow blast cells before chemotherapy. Expression of MDR proteins was considered as positive if at least 25% of the blast cells were stained by anti-MDR protein antibody. All pts received standard induction therapy (cytarabine, etoposide and idarubicin or daunorubicine).
Results: Blast cells was defined as Pgp-positive in 64.3% of cases, BCRP+ in 42.9%, MRP1+ in 46.4%, and LRP+ in 64.3% of cases. After induction therapy 20 (66,7%) pts achieved CR and 10 pts (33.3%) were resistant. MDR proteins expression was observed more frequently in resistant group, then in a sensitive one (70% vs 61% for Pgp, 70% vs 33% for MRP1, 100% vs 44% for LRP, 80% vs 22% for BCRP, respectively), difference for LRP and BCRP was statistically significant (p=0.004). Blast cells of all resistant pts expressed 2–4 MDR proteins (all studied proteins − 40%, 3 of them − 40% and 2 proteins − 20%). In a group of pts archived CR the blast cells expressed 3 proteins only in 2 cases (10%), and the expression of all 4 proteins we observed only in 1 patient (5%) with very short CR duration (3 months). Other pts from this group express only one studied protein.
According to chromosome analysis 18.2% of pts had favorable, 50% - intermediate and 31.8% unfavorable cytogenetic. Blast cells of all pts in cytogenetically unfavorable group expressed more then 1 protein, 3 or 4 MDR proteins expressed in 71,4% of cases. In favorable and intermediate cytogenetic groups blast cells expressed 1or 2 MDR proteins in 73,2% of cases, 3 or 4 proteins in 20%.
Conclusions: The expression of MDR proteins in AML has a prognostic value with respect to CR achievement in pts receiving standard antracycline-Ara-C regimens. The detection of any single protein didn’t have prognostic significance, only co-expression of 2 and more proteins predict unfavorable treatment outcome. We observed a correlation between the cytogenetic and the MDR phenotype.
Tetra-O-Methyl Nordihydroguaiaretic Acid Inhibits Growth and Induces Death of Leukemia Cells Independent of Cdc2 and Survivin.
Authors: Carter Bing Z. , Mak Duncan H. , Schober Wendy D. , Heller Jonathan , Andreeff Michael 
Published: April 2020

Abstract
Tetra-O-methyl nordihydroguaiaretic acid (M4N) was shown to induce G2 arrest in mammalian cells and suppress the growth of human xenograft tumors by inhibiting Cdc2 and survivin expression. We have previously shown that inhibition of survivin expression by antisense oligonucleotide induced G2 block and subsequent cell death in HL-60 cells. In this study, we examined the effect of M4N on leukemic cells and found that M4N inhibited growth and induced apoptosis in various leukemic cell lines and blasts from AML patients at concentrations from 5μM to 40μM. However, Cdc2 and survivin levels were not significantly affected. In agreement with these results, no G2 arrest was observed. Cell death and cell growth inhibition induced by M4N in leukemia cells were dependent neither on XIAP, Bcl-2, or Bcl-XL levels nor on caspase-8. Although M4N induced the loss of mitochondrial membrane potential in HL-60 cells, overexpression of Bcl-2 or Bcl-XL did not attenuate cell growth inhibition and cell death induced by M4N. M4N did not promote cell differentiation in HL-60 cells. Interestingly, significant inhibition of AKT and to a lesser degree of ERK phosphorylation was observed at 24 hours in OCI-AML3 cells treated with M4N. Collectively, our data showed that M4N inhibited cell growth and induced cell death in both leukemic cell lines and AML patient sample through a mechanism not mediated by Cdc2 and survivin inhibition and independent of death receptor and mitochondrial apoptotic pathways.
Effect of Valproic Acid on the Expression of P27Kip1 and Multidrug Resistance in HL60 Cells.
Authors: Yin Songmei , Nie Danian , Xie Shuangfeng , Li Yiqing , Wang Xiuju , Ma Liping 
Published: April 2020

Abstract
Multidrug resistance (MDR) was the main cause of treatment failure in leukemic chemotherapy. P170, the protein expressed from MDR-1 gene, play an important role in MDR. P27Kip1 was a member of cyclin dependent kinase inhibitor family. It was also a negative regulator in cell generation cycle. It also promoted cells apoptosis. Valproic acid (VPA) was a kind of histone deacetylace inhibitor which could inhibit cell cycle and induce apoptosis. In the current study, we investigated the effects of VPA on the expression of P27Kip1 and P170 of HL60 cells in vitro. HL60/HT cells were induced from HL60 cells by harringtonine (HT) in gradient concentrations. The P27Kip1 expression and P170 expression were tested in flow cytometry. We tested the expression of P27Kip1 and P170 in normal mononuclear cells, HL60 cells and HL60/HT cells, also the effects of VPA on P27Kip1 expression and P170 expression in HL60 cells and HL60/HT cells. The 50% inhibiting concentration (IC50) of vincristine for HL60/HT cells was 5.2 times higher than that for HL60 cells (0.078ug/ml vs. 0.015ug/ml). The IC50 of HT for HL-60/HT cells was 9.3 times higher than that for HL-60 cells (0.14μg/ml vs. 0.015μg/ml). The IC50 of Cytarabine for HL60/HT cells was 3.65 times higher than that for HL60 cells (0.73ug/ml vs. 0.20ug/ml). The expression of P27Kip1 in normal mononuclear cells was the highest, while that in HL60 cells was higher than HL60/HT cells (96.18±3.13% vs. 85.83±4.65% vs. 35.91±3.13%, one way ANOVA, P&lt;0.05). The expression of P170 in normal mononuclear cells and HL60 cells had no significant difference (0.54±0.32% vs. 0.62±0.31%, P&gt;0.05). But the P170 expression of HL60/HT cells was 6.71±1.61%, which was much higher than that of normal mononuclear cells or HL60 cells (P&lt;0.05). In HL60 cells, the expression of P27Kip1 increased after cultured with 1mmol/L VPA (92.21±3.43% vs. 85.83±4.65%, P&lt;0.05), but the expression of P170 didn’t change significantly (0.65±0.18% vs. 0.62±0.31%, P&gt;0.05). In HL60/HT cells, the expression of P27Kip1 increased after cultured with VPA (66.20±5.07% vs. 35.91±3.13%, P&lt;0.05), and the expression of P170 didn’t change significantly either (6.40±1.59% vs. 6.71±1.61%, P&gt;0.05). These results indicate that the P27Kip1 expression in normal mononuclear cells were higher than that in leukemia cells (HL60 cells), and the P27Kip1 expression in common HL60 cells were higher than that in MDR HL60/HT cells. VPA could increase the expression of P27Kip1 in HL60 cells and HL60/HT cells. VPA had no effect on the expression of P170 in HL60 cells or HL60/HT cells. That means, The MDR-reverse effect of VPA may not come from the P170 descent mechanism.