bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel Stilbene-Based Antileukemic Agents Active in P-Glycoprotein Expressing and Apoptosis-Resistant Acute Leukaemia Cell Lines.
Authors: Grimaudo Stefania , Di Cristina Antonietta , Abbadessa Vincenzo , Daniele Simoni , Roberti Marinella , Tolomeo Manlio 
Published: October 2019

Abstract
The stilbene scaffold is a basic element for a number of biologically active natural and synthetic compounds and in accordance with Evans’ definition it can be considered as a privileged structure. One of the most relevant and studied stilbenes is Resveratrol, a phytoalexin present in grapes, endowed with chemopreventive and chemotherapeutic properties and able to induce apoptosis in different cancer cell lines. Since reduced apoptosis has been implicated in the development and progression of malignant tumors and in the occurrence of chemoresistant phenotypes, resveratrol-induced apoptosis might therefore contribute to its antitumor activity. However, resveratrol is a not potent cytotoxic compound if compared with others chemotherapeutic drugs and it is scarcely active in P-glycoprotein expressing (MDR) and Bcr-Abl expressing leukaemia cells. With the aim to find new stilbene compounds active in resistant leukaemia cells we synthesized a small library of resveratrol analogs, bearing the 3,5-dimethoxy motif at the A phenyl ring and amino, methoxy and hydroxy moieties at the 3′-and/or 4′-positions. Moreover, we synthesized analogues which incorporate a phenyl ring as bioisosteric substitution of the alkenyl bridge. Among these new stilbenes we identified two compounds endowed with interesting antileukemic properties: a) a methoxylated cis derivative active at nanomolar concentrations in P-glycoprotein expressing HL60-R and CEM VBL100 acute leukaemia cell lines and in P-glycoprotein and Bcr-Abl expressing K562-ADR cell line which is resistant to apoptosis induced by most common anticancer agents, and b) a terphenyl derivative active in MDR and Bcr-Abl expressing cell lines. Both compounds induced apoptosis prevalently through the mitochondrial pathway. Differently from resveratrol and other stilbenes, the therphenyl derivative induced a block of cells in G0-G1 phase of cell cycle which was associated to the shift of the phosphorylation state of pRb from hyperphosphorylated to hypophosphorylated. Morover, low concentrations of this compound were able to induced a potent granulocytic and monocytic differentiation of HL60 cells.
Switching Death Pathways in AML; Induction of Necrosis by Arsenic, Ascorbic Acid and Antabuse (AAA).
Authors: Nichols Gwen L. , Wagner Michael J. , Dinnen Richard , Fine Robert L. 
Published: October 2019

Abstract
Virtually all chemotherapy drugs induce apoptosis. Cancer cells have multiple mechanisms of resistance to this form of cell death. Necrosis may have fewer mechanisms of resistance, providing a rationale to discover ways to switch cell death pathways from apoptosis to necrosis. Arsenic trioxide (ATO) is clinically effective against acute promyelocytic leukemia and studies have suggested efficacy in treating other malignancies, including other leukemias. ATO increases the intracellular concentration of reactive oxygen species and inhibits glutathione (GSH) reduction resulting in redox changes which activate caspases and induce apoptosis. Ascorbic acid (AA) and other agents which reduce glutathione concentrations and increase hydrogen peroxide concentrations have been shown to enhance the antitumor activity of ATO in vitro. This combination of agents is currently in clinical trials. In previous experiments using pancreatic cancer cell lines, disulfiram (DSF), in clinical use as an inhibitor of aldehyde dehydrogenasel, was added to the ATO/AA combination. Synergistic induction of cell death occurred. We sought to test this combination in myeloid cell lines. We tested the ATO/AA/DSF (AAA) combination ([ATO], 1uM; [AA], 100uM; [DSF], 0.125 uM) on two myeloid leukemia cell lines, KG1 and K562. After treatment for 48 hours in AAA, annexin and propidium iodide staining revealed an increase in annexin(+) PI(+) cells (necrosis) in the KG1 cell line that was similar to the effect in pancreatic cancer cells. Nearly five fold more KG1 cells underwent necrosis after exposure to AAA than with arsenic alone. Arsenic combined with ascorbic acid or disulfiram yielded an approximately two fold increase in necrosis. We propose that the mechanism of action of disulfiram is through quenching peroxide (H2O2) radicals generated by ATO and AA. The reducion of DSF leads to oxidation of GSH and NADH which decrease [ATP]i, shifting the cells from apoptosis to necrosis. K562 cells were largely resistant to the triple combination, remaining in a state of cytostasis after exposure to AAA. BCR-ABL positive cell lines, such as K562, have a relative increase in intracellular ROS. The lack of necrosis in K562 was surprising, and suggests that the activated BCR-ABL kinase may override this proposed mechanism. Imatinib has been shown to induce necrosis, and combinations including imatinib will be tested in BCR-ABL positive cell lines. To study the potential safety of this combination for human trials, AAA was tested on peripheral blood stem cells from normal donors (obtained after informed consent) and did not appear to have synergistic effects on colony formation as compared to the drugs applied individually. These results suggest a new mechanism of cell death, switching from apoptosis to necrosis, that can be targeted to treat leukemias and other malignancies. More studies to confirm the mechanism of this cell death are underway.
The Role of Bcl-2 in Apoptosis Induced by khat (Catha Edulis) in Acute Myeloid Leukemia Cell Lines.
Authors: Bredholt Therese , Dimba Elisabeth A. , Johannessen Anne C. , Costea Daniela , Francis G. W. , Vintermyr Olav K. , Gjertsen5 Bjorn T. 
Published: October 2019

Abstract
The herbal drug khat (Catha edulis Forsk.) is habitually used in Eastern Africa and the Middle East. The pharmacological activity of khat is due to its alkaloid fraction which initiates a rapid release of monoamine neurotransmitters from nerve terminals when ingested. Extracts from khat have been shown to induce cell death caspase-dependent apoptosis in human leukaemia cells. In this study, apoptotic sensitivity is correlated with endogenous protein expression of the anti-apoptogen Bcl-2, as well as transfection enforced over expression of Bcl-2. Exposure of a panel of human leukaemia cell lines to khat extract resulted in the development of similar apoptotic morphotypes. The sensitivity of the cell lines to khat induced apoptosis revealed a trend of inverse correlation with endogenous levels of Bcl-2. Stable or transient transfection of Bcl-2 inhibited khat-induced apoptosis, and the threshold for khat-induced apoptosis was lowered by blocking Bcl-2 synthesis with small interfering RNA. Together, these data suggest Bcl-2 modulation as a possible mechanistic pathway through which khat-induced apoptosis may occur.
IgH and TCRgamma Gene Rearrangements, Cyclin A1 and HOXA9 Gene Expression in Biphenotypic Acute Leukemias.
Authors: Golemovic Mirna , Sucic Mirna , Zadro Renata , Mrsic Sanja Davidovic , Mikulic Mirta , Rajic Ljubica , Labar Boris , Batinic Drago 
Published: October 2019

Abstract
Biphenotypic acute leukemia (BAL) represents a rare type of acute leukemia (AL) with the reported incidence of 4.0–8.5% and poor response to treatment. In adult BAL, poor prognosis is related to unfavorable cytogenetics and P-glycoprotein over-expression (Legrand et al, Br J Haematol1998;100:147–55). It is presumed that better knowledge of its biological features could improve the classification and clinical management of this rare type of acute leukemia. Due to paucity of data regarding biological parameters of BAL, in this study we have analyzed the rearrangements of immunoglobulin heavy chain (IgH) and T-cell receptor g (TCRg) genes, expression of cyclin A1 (CycA1) and HOXA9 genes as well as in vitro growth of 10 de novo BALs and compared them with 15 AML and 15 ALL, respectively. The diagnosis of BAL was established according to EGIL criteria. BAL represented 4.3% of adult and 3.0% of pediatric patients with de novo AL referred to our institution during the 1999–2003 period. Of 10 BALs studied, lymphoid BAL (L2) was identified in 3 children, myeloid BAL (M1 and M5) was identified in 3 adults and one child, BAL of undifferentiated cytomorphology (AUL) in 2 adult patients, whereas one 5-month-old child presented with two separate blast cell populations (L1+M5b, bilineal BAL). With regard to immunophenotype, the group of BAL patients was also heterogeneous: 8/10 expressed the combination of myeloid and B-lymphoid antigens and 2/10 expressed myeloid and T-lymphoid antigens. The majority of BAL expressed CD34 (89%). Cytogenetic analysis was obtained in 7 BAL patients, of whom 3 showed chromosome 11 aberrations and 1 had Ph+ chromosome. Our results indicate that IgH and TCRγ gene rearrangements correlated well with lymphoid BAL morphology. Interestingly, the majority of lymphoid BAL showed oligoclonal amplification of antigen-receptor genes, indicating the coexistence of several malignant clones at the time of presentation. The expression of CycA1 correlated well with myeloid and undifferentiated BAL morphology. In contrast, the expression of HOXA9, a marker associated with myeloid cell lineage, showed no strong correlation with BAL morphology. BAL showed almost equal in vitro growth in three different serum-free culture conditions (no addition of GF, addition of IL-7 and FL or GM-CSF and FL), indicating that their growth was less dependent on the addition of exogenous GFs. Finally, in vitro growth of blasts during a 7-day culture showed autonomous cell growth in 3/10 AML and 3/8 myeloid BAL samples tested, but not in any of the AL with lymphoid features. Finally, further studies are needed to confirm these findings and to extend research to a broader spectrum of cell markers aiming to give a better definition of this rare group of AL.
Risk Factors in Childhood Acute Lymphoblastic Leukemia: A Single Center Experience in a Developing Country.
Authors: Anak Sema S. , Agaoglu Leyla , Akcay Arzu , Saribeyoglu Ebru T. , Atay Didem Y. , Garipardic Mesut , Unuvar Aysegul , Karakas Zeynep , Devecioglu Omer , Ozturk Gulyuz , Gedikloglu Gunduz 
Published: October 2019

Abstract
Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy, with the survival rates up to 80–90%, but in high-risk patients the survival rate is still unsatisfactory. The aim of this study is to analyze the pediatric ALL data of a single pediatric university center between 1987–2005 retrospectively to identify risk factors effecting the event free survival (EFS). In order to determine the risk factors possibly effecting the survival, we analyzed gender, age, physical examination findings, blood cell count, FAB morphology, immunophenotyping results, translocations and extramedullary involvement. During the same period, chemotherapy regimens used and response to these protocols were also analyzed. A total of 372 cases [220 male (60%) and 151 female (41%)] were diagnosed and treated in our center between 1987–2005. The age distribution was as follows: 7% patients under 2 years, 68% between 2–10 years, 25% above 10 years of age. At diagnosis, 76% patients had a hemoglobin level <10gr/dl, 56% WBC >10.000/mm3, 74% platelet <100.000/mm3. Primary CNS involvement was positive in 2.5%, mediastinal mass in 8% of all patients. The morphological subtypes were as follows: L1 64%, L2 32%, L3 4%. Immunophenotypic results revealed T ALL in 22%, mature B ALL in 8% and B ALL (common, pre B, proB) in 70%. All patients received CCG modified BFM protocol (80% of all patients) until 1999. Since then high-risk patients were treated with the augmented BFM protocol and L3 patients BFM NHL 95 Protocol, while standard risk patients continued to get the CCG modified BFM protocol. The remission rate at day 33 was 97.8%. Eighty-one patients relapsed (68% patients isolated bone marrow, 16% bone marrow + extramedullary, 9% CNS, 7% testes). According to the univariate analysis of our patient population, the factors negatively effecting the EFS were age <1 year, hepatomegaly >2cm., white blood cell >50.000/mm3 and platelet count <20.000/mm3, L3 FAB morphology, ≥M2 bone marrow status at day 14; CD3, HLADR, CD45 and Tdt negativity. According to the multivariate analysis the most important negative risk factors effecting the EFS were age <1 year, hepatomegaly >2cm. and ≥M2 bone marrow status at day 14 and CD 45 negativity. After a follow up of 72±59 months (1–300 months) 58% of patients are alive & well, 28% were lost to follow up and 14% patients succumbed to death. Overall survival (OS) for 60&120 months follow up were 83%, 83% and event free survival (EFS) 72%, 70% respectively. In conclusion, in ALL patients risk assessment is very important to conduct appropriate therapy. Identifying such factors and implementing risk adapted therapy will improve our treatment results decreasing the toxicity rates in pediatric ALL. Therefore treatment of all ALL patients still remains a challenge.
Peculiar Morphological, Cytochemical, Biochemical and Immunophenotyping Features in One Case of Acute Myeloid Leukaemia at the Onset.
Authors: Zini Gina , Rossi Elena , Garzia Mariagrazia , Rumi Carlo , Laurenti Luca , Di Mario Antonella , Sica Simona 
Published: October 2019

Abstract
On July 28th 2005, a 53-year old woman was admitted to our Hematology Dpt. with fever (37.5 C), fatigue, marked gingiva hypertrophy, mild hepatomegaly and absence of lymphoadenopaty and splenomegaly. Laboratory tests showed high leukocyte count of 182 x109/L, moderately increased platelet count (438 x109/L), normocytic anemia (10,9 g/dl, MCV 84 fl). Biochemical parameters, including lysozyme, were in the normal range except for high level of lactate dehydrogenase (2524 UI/l). Peripheral blood (PB) smear showed the presence of 94% of blasts, without evident granules. At the cytochemical myeloperoxidase staining blast cells revealed the presence of single or multiple Auer rods, while cytoplasmic granules were positive to the α-naphtyl butyrate esterase. In the bone marrow (BM) aspirate blasts were 80% showing same morphological and cytochemical features as in peripheral blood, while the granulocytic maturating series was 14%. No evidence of morphologically identifiable monocytic series in PB neither in BM. Megakariocytes were slightly increased and there was trilineage dysplasia. Blast immunophenotyping in PB and in BM was as follow: CD45, CD33, CD13, CD7 and HLA-Dr positive, 36% MPO positive and 48% co-express CD11c an CD117. Moreover blasts were CD14, CD19 and CD56 negative. FAB diagnosis was AML-M4. Interphase Fluorescence in situ Hybridization (FISH) for detection of AML1/ETO and bcr/abl gene rearrangements was negative. After treatment with 2 g hydroxyurea and leucapheresis, the WBC count was still high (140 x109/L) while after 1g of aracytin, WBC count decreased to 31000/mm3. Patient is presently enrolled into the GIMEMA protocol AML-12.
This case shows at the onset following abnormalities:
- an increased platelet count is a rare evenience in an AML at the onset; - negativity for lysozyme; - absence of CD14; - presence of Auer rods in quite all the blast population, which is a very rare evenience associated with monocytic subtypes of acute myeloblastic leukemia (AML); - atypical homogenous cytochemical pattern of blasts, showing Auer rods MPO positive and granules ANBE positive; - absence of any morphological differentiation of monocytic series. S4479
Reliability of Computer Algorithm-Based Binding Predictions for the Identification of Leukemia Antigens.
Authors: Gomez-Nunez Marta , Pinilla-Ibarz Javier , Dao Tao , Korontsvit Tatyana , Zakhaleva Victoriya , May Rena J. , Scheinberg David A. 
Published: October 2019

Abstract
Major Histocompatibility Complex class I (MHC-I) molecules present antigenic peptides to T cells on the cell surface as a prerequisite for stimulating cytotoxic T cell response. Thus, the ability to reliably identify the peptides that can bind to MHC molecules is of practical importance for rapid vaccine development. Several computer-based prediction methods have been applied to study the interaction of MHC class I/peptide binding. Here we have compared three of the most commonly used predictive algorithms BIMAS, SYFPEITHI and Rankpep with actual binding of HLA-A*0201 peptides in vitro. Forty six HLA-A*0201 peptides were selected from several target oncoproteins: Wilms’ tumor (WT1), native and imatinib- mutated bcr-abl p210 and JAK2 protein. Experimental peptide binding to HLA-A*0201 was assessed using a MHC stabilization assay on T2, TAP deficient cells. Peptides were considered to show positive in vitro binding if the mean fluorescence was at least 50 % of the binding of a high affinity reference peptide. Peptides qualified as positive in vitro if the BIMAS score was ≥ 100, the SYFPEITHI score ranked ≥ 24 or the Rankpep was ≥ 50. Results are summarized below:
BIMAS SYFPEITHI RANKPEP Sensitivity 84 % 72 % 60 % Specificity 76 % 71 % 81 % Positive Predictive Value 84 % 72 % 60 % Negative Predictive Value 80 % 68 % 63 %
Combining two or more computer methods did not appear to improve the predictive value. In conclusion, of the three predictive algorithms, the best correspondence with the actual MHC binding was demonstrated with the BIMAS algorithm. Predictive computer algorithms are important for preselection of potential T-cell epitope candidates for the application in vaccine design.
Redirection of CMV Specific CTL towards B-CLL Via CD20 Targeted HLA/CMV Complexes.
Authors: Mous Rogier , Savage Philip Savage , Remmerswaal Ester BM , van Lier Rene A.W. , Eldering Eric , Van Oers Marinus H.J. 
Published: October 2019

Abstract
Because B cell chronic lymphocytic leukemia (B-CLL) can not be cured with current therapies, but in general has a slow progression and rather long median survival, it is considered an attractive candidate for active T cell mediated immunotherapy. However B-CLL cells have poor antigen presenting capacity because they express low levels of co-stimulatory molecules. Moreover, most immunotherapeutic strategies require knowledge of the eliciting tumor antigen and/or ex vivo manipulation of patient cells. To circumvent these drawbacks we aim to redirect existing viral immunity towards B-CLL. Previously, we have shown that in patients with B-CLL considerably expanded numbers of cytomegalovirus (CMV)-specific CD45RA+CD27 CD8+ cytotoxic T cells are present (W. Mackus et al. Blood2003; 102:1057). These cells are potent cytotoxic effector cells when directed against B-CLL cells loaded with CMV peptide (A.Kater et al. Br.J. Haematol.2004; 126:512). In the current study, we apply a novel bridging reagent to redirect CMV-specific CTL to specifically target B-CLL. The targeting complex is composed of a streptavidin fused anti-CD20 single chain variable fragment (scFv) in combination with biotinylated MHC class I molecules containing CMV pp65 peptide (HLA/CMV). We demonstrate that this complex is stable on the cell surface for ≥24 hours, and that B-CLL cells coated with this CD20-HLA/CMV complex can be lysed by autologous CMV-specific CD8+ CTL with similar efficiency as B-CLL cells directly loaded with CMV-peptide. Killing occurs at scFv CD20 concentrations of ≥100 ng ml−1 and HLA/CMV concentrations of ≥20 ng ml−1. Lysis of CD20-HLA/CMV complex coated CLL cells could not be blocked by anti-LFA1 antibodies, in contrast to B-CLL cells directly loaded with CMV-peptide, indicating a different immunological synapse. HLA-A2 positive B-CLL cells coated with HLA-B7 /CMV complexes were only lysed by HLA-B7 positive CMV-specific CTL, whereas HLA-A2/CMV complex targeted HLA-A2 positive B-CLL cells were unaffected by HLA-B7 positive CMV specific CTL, proving HLA restriction of the killing.. Furthermore, CD20-HLA/CMV complex coated B-CLL cells induce both proliferation and cytokine production (interferon γ, tumor necrosis factor α, and macrophage inflammatory protein-1 β) in CMV-specific CD8+ T cells. Thus, CD20-HLA/CMV complexes elicit both immune activation and direct cytotoxicity towards B-CLL cells. The findings of our study constitute a necessary step towards possible application of CD20-HLA/CMV complexes for immunotherapy of B cell malignancies. It is obvious that this recently recognized capacity to redirect existing antiviral immunity towards tumor cells has a utility in cancer immunotherapy far beyond CMV and B-CLL.
The Results of Molecular Relapses Treatment in Acute Promyelocytic Leukemia (APL) Patients.
Authors: Shuravina Elena N. , Parovitchnikova Elena N. , Demidova Irina A. , Olshanskaia Yulia V. , Misiurin Andrei V. , Savchenko Valeri G. 
Published: October 2019

Abstract
Nearly all de novo APL patients (pts) undergo complete remission (CR) when treated with all- trans-retinoid acid (ATRA) plus chemotherapy. Nevertheless a significant portion (20%) of these pts ultimately relapse during the first 2 years of therapy. Minimal residual disease (MRD) monitoring using RT-PCR is widely recognized method for detection of molecular relapses (MR) in APL pts during hematological remission. However, the precise MR definition and significance of therapy changing when MR is detected are still controversial. We report the results of molecular monitoring and MR treatment in 40 pts (17 male, 23 female, median age = 33) who were included in the APL studies from 1997 to 2005. The induction and consolidation consisted of four 7+3+ATRA courses or four courses of 5 days Daunozome + ATRA or AIDA-protocol. Maintenance (MT) was performed for 2 years of CR with chemotherapy (5+2 courses) or chemotherapy combined with ATRA or monotherapy with ATRA+INF-alfa after Daunozome. RT-PCR for PML/RARα was performed on fresh marrow aspirates in all pts before treatment and periodically (2–3month) during 2 years after CR induction (2–18 investigations, median 6, for each pt). RT-PCR was performed using recommendations of BIOMED-1 Concerted Action (1999). MR was defined as probable if chimeric transcript was detected once and was not find out by second investigation and as proved when PML/RARA was detected at least twice by consecutive investigations (in 2–4 weeks). In case of proved MR we changed the type of MT. In pts with early MR (<12 mo of CR) MT was changed to Methotrexate+6-Mercaptopurine +ATRA. Pts with late MR (> 12 mo of CR) were treated with ATRA+IFN-α. After two hematological relapses (HR) in the group of probable MR we started to change the type of MT even if MRD was detected once. The Table 1 reflects the effect of MT changes on the frequency of HR in pts with MRs.
Table 1 Maintenance Probable MR Proved MR No MR/relapsed MT changed /pts relapsed MT unchanged/pts relapsed MT changed/pts relapsed MT unchanged /pts relapsed Chemotherapy (n=19) 3/0 2/1 3/0 1/1 10/1 Chemo+ATRA (n=15) - 6/1 1/0 - 8/1 ATRA+IFN- α (n =6) 1/0 1/1 1/0 - 3/2 Total (n=40) 13/3 6/1 21/4
Our data shows the equal frequency of HR in pts with and without MR: 4/19 and 4/21. The absence of difference is probably due to the treatment changes in case of MR. We also can admit that ATRA monotherapy as maintenance is ineffective approach (3 MR and 3 HR). We revealed the statistically significant difference in the probability of hetmatological relapse in pts with MR in whom MT was changed (0 from 9 relapsed) and not changed (4 from 10 relapsed) (p= 0,04). So it seems reasonable that in proved and probable MRs MT should be changed. However, more investigations should be done for definition of the best postremission treatment strategy in APL pts with MRD.