bluuebunny/crossref_metadata_2025_split huggingface dataset:
mTOR as Therapeutic Target for T-Cell Leukemia: Synergism with Conventional Cytotoxic Drugs and Signaling Inhibitors.
Authors: Batista Ana , Barata Joao T. , Costa Lara F. , Sallan Stephen E. , Carlesso Nadia , Nadler Lee M. , Cardoso Angelo A. 
Published: April 2020

Abstract
Targeted disruption of signaling pathways essential for tumor cell survival and proliferation offer great promise for the design of more efficient and specific therapies. mTOR plays a central role in sensing mitogenic, nutrient and energy signals, and in the integration of different signaling pathways. Moreover, increasing evidence implicates mTOR in tumorigenesis and in the maintenance of transformed phenotypes. Therefore, we hypothesized that the mTOR pathway may play a significant role in T-cell acute lymphoblastic leukemia (ALL). BM and peripheral blood specimens from 15 pediatric patients were analyzed for the phosphorylation status of two downstream substrates of mTOR, S6 Ribosomal Protein and eIF4G. In all cases, primary leukemia T cells showed marked phosphorylation of S6 Ribosomal Protein (Ser235/236) and phosphorylation of the eukaryotic initiation factor eIF4G (Ser1108), showing that the mTOR pathway is constitutively active in T-ALL cells. Since leukemia T cells did not show significant basal phosphorylation of Akt/PKB, this observation suggests that the mTOR activation observed in T-ALL is Akt-independent. Specific blockade of mTOR by Rapamycin (100nM) reduced or abrogated phosphorylation of S6 ribosomal protein. Moreover, the mTOR blockers Rapamycin (10–100nM) and CCI-779 (10–100nM) significantly inhibited cell survival, and IL-7-promoted proliferation (40% to 85% inhibition) and cell cycle progression of T-ALL cells. Since we have shown previously that PI3K/Akt is critically involved in T-ALL responses to exogenous stimuli, we next evaluated whether inhibition of PI3K/Akt signals would synergize or potentiate the effects of mTOR blockade. We observed that the PI3K-inhibitor LY294002 (10μM) synergized with Rapamycin to abrogate IL-7-promoted leukemia T-cell proliferation. Finally, we explored the possibility that mTOR blockade can enhance the cytotoxic effects on T-ALL of the conventional drugs Dexamethasone (100nM) and Doxorubicin (100nM). Rapamycin potentiated the cytotoxic effects of both Dexamethasone (1.3 to 10 fold) and Doxorubicin (1.7 to 7.3 fold), suggesting that the combination of mTOR blockade with chemotherapy can improve the anti-leukemia efficacy of conventional regimens. In conclusion, we observed that the mTOR pathway is constitutively activated in primary leukemia T cells, and that the mTOR blockers Rapamycin and CCI-779 significantly inhibit T-ALL survival and proliferation. In addition, Rapamycin potentiates the inhibitory activity of other signaling inhibitors and the cytotoxic effects of the conventional drugs Dexamethasone and Doxorubicin. This study suggests that the mTOR pathway is a valid target for the treatment of T-ALL and lay the groundwork for the inclusion of mTOR blockade in the current therapeutic regimens.
The Survival of Multiple Myeloma Patients: A Single Institution Study.
Authors: Berneman Zwi N. , Verstraete An-Sofie , Gadisseur Alain , Van de Velde Ann , Schroyens Wilfried A. 
Published: April 2020

Abstract
Background: For a long time, multiple myeloma has been a disease with a poor outcome. High dose (melphalan) chemotherapy followed by autologous stem cell transplantation has been reported to improve the overall and progression-free survival of these patients.
Objective: To determine the survival of multiple myeloma patients treated with conventional chemotherapy and compare it with that of patients treated with high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation.
Design/Methods: 83 myeloma patients treated at a single institution were included in this retrospective study. They were divided into two groups: one group of patients who were received high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation (n=42) and one group of patients who only received conventional chemotherapy and were eventually also treated with thalidomide and/or corticosteroids (n=41). The distribution of the stages of the disease according to Salmon and Durie were similar in both groups of patients. For both groups, the overall and progression-free survival was calculated.
Results: In the general analysis, myeloma patients who underwent an autologous transplant had a significantly longer overall survival (58.8 vs. 52.2 months, p=0.036) and progression-free survival (39.6 vs. 11.8 months, p &lt; 0.001) in comparison with the conventional chemotherapy group. If analysis was restricted to those patients who were transplanted as a first-line treatment, there was no significant difference in overall survival in comparison with conventional chemotherapy (51.8 vs. 52.2 months, p= 0.422); progression-free survival was significantly better in the first-line transplant arm as compared to the conventional chemotherapy arm (35.4 vs. 11.8 months, p= 0.003). As the median age in the transplant arm was significantly lower than in the conventional chemotherapy arm, we also performed a sub-analysis of patients who were between 60 and 70 years of age at diagnosis; there was no significant difference in overall survival between the two groups (60.7 vs. 69.5 months, p= 0.656), while the progression-free survival was again better in the autologous transplant group as compared to the conventional chemotherapy group (41.0 vs. 8.4 months, p= 0.020).
Conclusion: High-dose chemotherapy and autologous stem cell transplantation in the treatment of myeloma is associated with improved progression-free survival and in the general analysis, with improved overall survival. The overall survival of patients who were only treated with conventional chemotherapy is somewhat higher (more than 4 years) as compared to that of historical controls (2–3 years).
Retroviral Gene Transfer with Triple Genetic Reporter Genes into Human Cord Blood CD133+ Cells.
Authors: Niu Ting , Najjar Amer M. , Robinson Simon N. , Yang Hong , Decker William K. , McMannis John D. , Ng Jingjing , Thomas Michael W. , Champlin Richard E. , Gelovani Juri G. , Shpall Elizabeth J. 
Published: April 2020

Abstract
Umbilical cord blood (CB) is used increasingly as a source of hematopoietic support in bone marrow transplant patients lacking family or unrelated donors. Little is known about human CB with respect to in vivo migration, homing, long-term viability, the organ-specific checkpoints and its differentiation. In order to study CB migration and homing, the gibbon ape leukemia virus (GALV)-pseudotyped retroviral gene transfer technique was developed to genetically modify CB CD133+ cells with triple reporter genes which encode enhanced green fluorescent protein (eGFP), luciferase, and herpes simplex virus type one thymidine kinase (HSV1-tk). The novelty of this approach is that it allows multimodal repetitive non-invasive imaging using fluorescence, bioluminescence (BLI), and nuclear imaging techniques, respectively. CD133+ cell fractions were isolated from human CB using the MidiMACS device (Miltenyi). To facilitate transduction, CB CD133+ cells were stimulated with 100ng/ml each of stem cell factor (SCF), granulocyte colony-stimulating factor (G-CSF) and thrombopoietin (TPO) in alpha-MEM medium supplemented with 20% fetal bovine serum. After 3, 5, 7 or 14 days of stimulation, CB cells were transduced by RetroNectin (TaKaRa)-assisted gene transfer. RetroNectin, recombinant human fibronectin fragment CH-296, can provide colocalization of retroviral particles and target cells. Specifically, 6-well plates were coated with 5ug/cm2 RetroNectin for 2 hours at room temperature, followed by preloading with fresh virus-containing medium (VCM) for 4 hours at 37°C. VCM was then removed and the CB cells were added in medium containing cytokines for 2 or 3 days. This approach resulted in &gt; 90% transduction of control U87 human glioma cells and up to 36% transduction of CD133+ CB cells. Preliminary experiments suggested that optimal transduction appeared to be at day 7 of CB stimulation. When compared to non-RetroNectin coated plates, this approach showed a 5- to 11- fold increase in eGFP+ cells as determined by flow cytometry, increasing the transduction efficiency from &lt; 5% to a maximal 36%. The addition of polybrene, a cationic polymer, to this process did not improve transduction efficiency. Studies are underway to visualize retrovirally-transduced CB CD133+ cells in NOD/SCID mice in vivo. The ability to trace the fate of CD133+ cells following transplantation may allow a better understanding of the mechanisms of migration, homing and long-term viability.
Intratumoral, Injection of Adenoviral Flt3 Ligand Has Therapeutic Activity in Association with Increased Intratumoral Levels of T Cells but Not Dendritic Cells.
Authors: Talmadge James E. , Kurz Scott G. , Fields Randy R. , Agrawal Devendra K. , Singh Rakesh K. , LaFace Drake M. , Ashour Abdel-kader E. , Shafer Lora R. , Solhwim Joyce E. 
Published: April 2020

Abstract
Fms-like tyrosine kinase 3 ligand (Flt3L) is a growth factor for dendritic cells (DCs), hematopoietic stem cells, and natural killer (NK) cells in vivo. Ten daily injections of Flt3L, systemically expands DCs, whereas a single injection of an adenovirus vector with the Flt3L transgene (Adv-Flt3L) significantly expands DCs as soon as 2 days following intravenous (iv) injection. The increases in DC numbers, following iv injection, remains at near peak levels from day 6 through day 16. Maximal DC expansion occurs following the iv injection of 1011 virus particles, such that eight days following the iv injection of Adv-Flt3L it induced an 8 fold increase in splenic CD11c+CD11b−CD8a+ cells (immune augmenting DCs), a 6 fold increase in splenic CD11c+B220+ plasmacytoid DCs, and a 9 fold increase in splenic CD11c+CD11b+ cells (immunosuppressive DCs). The increase in DC numbers and cellularity returns to near normal levels by 22 days following iv injection of Adv-Flt3L. Despite the 2–3 fold increase in spleen cellularity and significant expansion of DCs in the spleen, blood and lungs by the iv injection of Adv-Flt3L, this route of administration has minimal to no therapeutic activity for orthrotopic mammary tumors, even when therapy is initiated against small primary tumors. In contrast, the intratumoral injection of Adv-Flt3L has significant therapeutic activity against orthrotopic mammary tumors including mice in which therapy was initiated against large tumors. Unexpectedly, no significant increase in DC infiltration of the tumor was observed following iv or intratumoral Adv-Flt3L administration. In contrast, the number of tumor infiltrating CD4+ and CD8+ cells was increased following intratumoral but not iv Adv-Flt3L administration, suggesting an association with therapeutic activity. Adv-Flt3L injection also induced DC expansion in the spleen, PB and lungs in cl-66, mammary adenocarcinoma-bearing mice. Injection of adv-Flt3L (iv or intratumoral) also stimulated the expansion of T-cells (both CD4+ and CD8+) and a type 1 T cell response as measured by qRT-PCR. Further, the therapeutic activity and increased mitogenic responses by splenic lymphoid cells to Con-A and IL-2 was not depressed in mice bearing cl-66 tumors and the effect of Adv-Flt3L, while partially associated with the Adv vector, was significantly higher in mice injected with Adv-Flt3L.
Conjugation of Plasminogen Activators to Carrier Erythrocytes Imparts New Biological Properties to Their Soluble Counterparts.
Authors: Ganguly Kumkum , Krasik Tatiana , Bdeir Khalil , Cines Douglas B. , Muzykantov Vladimir R. , Murciano JuanCarlos 
Published: April 2020

Abstract
Conjugation of plasminogen activators (PA) to carrier red blood cells (RBC) generates a new agent (RBC/PA), which selectively lyses nascent blood clots. In this work, we studied two types of RBC/PA conjugates, carrying Alteplase (tissue type plasminogen activator, tPA) or Reteplase (an engineered form of tPA, Ret). Compared to non-conjugated 125I-PA counterparts, both 125I-tPA and 125I-Ret coupled to 51Cr-RBC via biocompatible biotin-streptavidin cross-linker showed markedly prolonged circulation in rats and mice. Despite slightly faster blood clearance, RBC/tPA retained significantly higher fibrinolytic activity in circulation than RBC/Ret. In part, the higher fibrinolytic activity of RBC/tPA vs RBC/Ret in the circulation was due to its lessened susceptibility to plasma inhibitors. Analysis of amidolytic activity of RBC-coupled vs free tPA and Ret using chromogenic substrates in vitro revealed that coupling to RBC rendered Ret, but not tPA, insensitive to stimulation of fibrinolytic activity by fibrin. In vitro binding assay in cultural wells showed that RBC/tPA specifically binds to fibrin clot (6±0.2x104 RBC/tPA bound per well vs. 1±0.4x104 RBC/Ret or 7.3±0.6x103 naive RBC). RBC/tPA also bind specifically to immobilized fibrinogen and plasminogen (8±2x104 and 2±0.4x104 RBC/well), but not to non-cleavable plasminogen, collagen, fibronectin or thrombospondin (&lt;1.1±0.3x103RBC/well). Neither RBC/Ret nor naïve RBC bind to these proteins (&lt;1.1±0.2x103 RBC/well). Therefore, RBC/PA complexes display a considerable functional diversity, a result of interplay between the pharmacokinetic features offered by carrier RBC, individual features of a given PA and alterations of the latter caused by RBC coupling. In theory, this diversity may enhance flexibility and utility of potential applications of RBC/PA for thromboprophylaxis.
IL-6 and Anemia of Inflammation.
Authors: Rivera Seth , Gabayan Victoria , Ganz Tomas 
Published: April 2020

Abstract
BACKGROUND: Anemia of inflammation (AI, anemia of chronic disease) is an iron-restricted anemia caused by hepcidin limiting the supply of iron for erythropoiesis. We had previously shown that IL-6 was necessary for the induction of hepcidin and the development of hypoferremia during acute inflammation in vivo (Nemeth E et al, JCI, 2004). In vitro, IL-1 (Lee P et al, PNAS, 2005) and TGF-β (unpublished data) can also stimulate hepcidin production in primary murine hepatocytes in an IL-6 independent fashion.
METHODS: We sought to determine whether IL-6 was necessary for the development of AI using a model of chronic peritonitis in IL-6 deficient mice and wild type (WT) controls.
RESULTS: IL-6 deficient mice developed anemia of similar severity as their WT counterparts. WT mice developed microcytic anemia consistent with inflammation-induced iron restriction. In contrast, the inflamed IL-6 deficient mice developed mild macrocytosis indicating markedly different erythrocyte iron metabolism. Hepcidin mRNA increased in WT mice but not IL-6 deficient mice in response to inflammation.
CONCLUSION: IL-6 is the principal regulator of hepcidin during acute and chronic inflammation. However, anemia still occurs in the absence of IL-6. The difference in mean corpuscular volume implies that the mechanism of anemia in IL-6 deficient mice is likely different than in WT mice.
Prevalence and Prognostic Significance of c-KIT Mutations in Pediatric CBF AML Patients Enrolled on Serial CCG/COG Protocols.
Authors: Pollard Jessica , Alonzo Todd , Gerbing Robert , Zeng Rong , Hirsch Betsy , Raimondi Susana , Heerema Nyla , Woods William , Lange Beverly , Hurwitz Craig , Arceci Robert , Radich Jerald , Bernstein Irwin , Heinrich Michael , Meshinchi Soheil 
Published: April 2020

Abstract
Pediatric patients with core binding factor (CBF) acute myeloid leukemia (AML) [t(8;21) and inv(16)] typically have favorable outcome, yet 20–40% of patients will relapse, suggesting that additional events may impact disease response. Recently, mutations of the c-KIT receptor tyrosine kinase gene were implicated as a prognostic factor in adults with CBF AML. The prevalence and prognostic significance of c-KIT mutations in pediatric CBF AML has not been well established. We analyzed diagnostic specimens from 156 pediatric patients with CBF AML enrolled on serial AML protocols CCG 2891, 2961 and COG AAML03P1 with 3 different methodologies (direct sequencing, HPLC, and micro capillary electrophoresis) to identify mutations in c-KIT exons 8 and 17. Mutations were detected in 27 samples (17%); 13 (48%) involved exon 8, 13 (48%) involved exon 17, and 1 (4%) involved both regions. Of 15 inv(16) specimens with c-KIT mutations, 9 (60%) involved exon 8, 5 (33%) involved exon 17, and 1 (7%) affected both exons. In contrast, of 12 t(8;21) specimens with c-KIT mutations, 4 (33%) involved exon 8 whereas 8 (67%) affected exon 17. Clinical outcome data from 98 CBF AML patients enrolled on CCG 2961 was analyzed to determine the prognostic significance of c-KIT mutations in this patient population. CBF AML patients with c-KIT mutations had similar clinical characteristics (age, sex, race, presenting white blood cell count and blast percentage) to those CBF AML patients without c-KIT mutations. There was no difference in the rate of complete remission (CR) (c-KIT mutations, 88% vs. no mutation 92%; p=0.645), overall survival (OS) at 5 years from study entry (c-KIT mutation, 68% vs. no mutation 71%; p=0.733), or corresponding relapse risk (RR) from the time of CR (c-KIT mutations, 33% vs. no mutation 31%; p=0.92). The relative prognostic significance of the location of c-KIT mutation (i.e. exon 8 or exon 17) was also evaluated. No differences were found in CR rates (exon 8 mutation, 100% vs. exon 17 mutation, 75%; p= 0.467), OS from CR (exon 8 mutation, 86% vs. exon 17 mutation, 47%; p=0.088), or corresponding RR at 5 years from CR (exon 8 mutation, 29% vs. exon 17 mutation, 50%; p=0.517). This study demonstrates that the prevalence of c-KIT mutations in pediatric CBF AML patients enrolled on serial CCG/COG AML protocols is lower than that observed in adult studies. We found that c-KIT mutations lacked prognostic significance in pediatric CBF AML patients treated with intensive chemotherapy on CCG 2961, though there was a suggestion that patients with exon 17 mutations may have worse outcome. Outcome data from the entire cohort (CCG 2891, 2961 and COG AAML03P1) will be analyzed to determine whether this finding is significant with larger scale analysis.
Delayed Response to Lenalidomide in International Prognostic Scoring System (IPSS) Low Risk Myelodysplastic Syndrome (MDS).
Authors: Tubb Erev E. , Besa Emmanuel C. , Giagounidis Aristoteles , Fonseca Gustavo A. 
Published: April 2020

Abstract
Lenalidomide was approved by the US Food and Drug Administration in December of 2005 for the treatment (tx) of transfusion-dependent anemia (TDA) in patients (pts) with MDS and chromosome 5q deletions (del5q). In the trial that secured the approval, 67% of 148 pts achieved red blood cell (RBC) transfusion independence (TI) with a median time to TI of 44 weeks. 90% of pts who achieved TI did so by completion of 3 months of therapy. In a companion study (MDS-002) pts lacking del5q the frequency of TI was only 26%. We report three cases of IPSS Low risk myelodysplasia MDS with a delayed response to lenalidomide. The patient characteristics are outlined in Table 1.

Following a 6 to 11 month trial of lenalidomide for TDA in IPSS Low risk MDS delayed TI can occur 1 to 4 months after discontinuation of lenalidomide. Delayed TI was not associated with a cytogenetic response. The duration of response can last from 11 months to 16 months. Lenalidomide, a thalidomide analogue, is an immunomodulatory agent with anti-angiogenic and anti-neoplastic properties. Effects of lenalidomide such as increased production of interleukin-2 and interferon-γ have been linked to the appearance of lymphoid aggregates of a mixture of B and T cells in the BM specimens of responders. TI has previously been correlated with suppression of the del5q clone. In our patients, TI was achieved after discontinuation of lenalidomide following a reasonable ineffective trial and no apparent suppression of the del5 clone. A similar phenomenon was described by Raza, et al. in a single MDS patient treated with thalidomide. Interestingly, one patient had lymphoid aggregates of B and T cells throughout treatment, raising the possibility that the immune stimulatory effects of lenalidomide may be a variable against the del5q clone. The transient response may be due to immunomodulatory effects but persistence of the del5q clone in two of our patients and and dysplasia in the other, is responsible for the relapse after the immune response has waned. Re-treatment with lenalidomide in our patient did not prolong or re-induce another response. References Giagounidis AAN, Germing U, Aul C: Biologic and prognostic significance of chromosome 5q deletions in myeloid malignancies. Clin Cancer Res 2006, 12:5–10. List A, Kurtin S, Roe DJ, et al.: Efficacy of lenalidomide in myelodysplastic syndromes. N Engl J Med. 2005, 352:549–557. List A: Recent advances in the treatment of MDS. Clin Advances in Hematology. Oncology. 2007, Supp 10, Vol 5, Issue 7: 4–5 Raza A, Meyer P, Dutt D, et al. Thalidomide produces transfusion independence in long-standing refractory anemias of patients with myelodysplastic syndromes. Blood. 2001 Aug 15, 98(4):958–65.
Results of an Exploratory Study of Oral (po) and Intravenous (iv) Clofarabine in Patients with Myelodysplastic Syndrome.
Authors: Faderl Stefan , Garcia-Manero Guillermo , Gandhi Varsha , Ravandi Farhad , Borthakur Gautam , Thomas Deborah A. , Ferrajoli Alessandra , Estrov Zeev , Plunkett William , Byrd Anna , Kwari Monica , Kantarjian Hagop M. 
Published: April 2020

Abstract
Clofarabine (CLO) is an adenosine nucleoside analog with activity in adult acute myeloid leukemia (AML). Its activity in MDS is less well defined. To evaluate the activity and safety of CLO in MDS we designed two phase II studies with iv CLO and po CLO, respectively. Pts were eligible if they had MDS with ≥ 5% blasts, fell into IPSS intermediate-2 and high-risk groups, or had CMML. No prior intensive chemotherapy or high-dose cytarabine was allowed. Hematopoietic growth factor support was permitted. In the iv study pts were adaptively randomized to receive CLO 15 or 30 mg/m2 iv daily x 5 every 4–6 weeks. The second study used a starting dose of CLO 40 mg/m2 orally daily x 5 every 4–6 weeks (assuming oral bioavailability about 50%), which was then decreased to 30 mg/m2 orally daily x 5. Thirty pts (18 RAEB, 6 RAEB-T, 6 CMML) have been treated. Assignment by IPSS for RAEB and RAEB-T pts: 10 high-risk, 10 intermediate-2, and 4 intermediate-1. Fifteen pts received iv CLO and 15 po CLO. Median age was 68 yrs (range 57–86). Median number of prior therapies was 1 (0–4). Twenty (67%) pts received prior decitabine or azacitidine. Karyotype was abnormal in 24 (80%) pts, including 10 pts with −5/−7 abnormalities. Responses were determined according to International Working Group criteria (IWG). Twenty-seven pts were evaluable for response (2 pts too early, one refused further treatment on day 4 of first course). Eleven (41%) pts responded [7 (26%) CR, 2 (7%) HI, 2 (7%) clinical benefit (CB)] (see table).
Response (%) Route Dose (mg/m2) N CR HI CB po 40 6 - - 1 (17) 30 6 1(17) 2 (33) 1 (17) iv 30 6 2 (33) - - 15 9 4 (44) - -
Response by IPSS: 67% intermediate-1, 44% intermediate-2, 40% high. Twenty-seven pts are evaluable for toxicities. Grade ≥ 3 toxicities occurred in 8 of 13 pts on iv CLO (rash, hyperbilirubinemia, elevated transaminases, elevations of creatinine, acute renal failure) and 4 of 14 pts with po CLO (rash, hyperbilirubinemia, elevated transaminases). Myelosuppression resulting in febrile episodes and hospitalizations with both iv and po CLO was ubiquitous, but prolonged myelosuppression (&gt; 42 days) was rare. In summary, CLO has activity in pts with higher-risk MDS. The optimal dose and schedule for po and iv CLO have not been defined yet. Lower doses of CLO are associated with responses. Correlative PK studies may help to provide further support for optimal dose and route of administration of CLO in pts with MDS.