bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth Hormone – Insulin-Like Growth Factor –I (IGF-I) Axis and Bone Mineral Density In Adults With Thalassemia Major (TM)
Authors: Yassin Mohamed A. , Soliman Ashraf T , Desanctis Vincenzo
Published: October 2019

Bone disease and short stature are frequent clinical features of patients with beta-thalassaemia major. Dysfunction of the GH-IGF-1 axis has been described in many thalassaemic children and adolescents with short stature and reduced growth velocity.

Assessment of the GH-IGF-1 axis in short adults with TM after attainment of final height may be required to select those who are candidates for replacement therapy and to prevent the development of bone disease. The aim of our study was to investigate GH secretion in adult thalassaemic patients in relation to their bone mineral density (BMD) and serum ferritin concentrations.

Patients and methods

We performed clonidine stimulation test in 30 thalassaemic patients (18 males, 12 females) with a mean age of 31.5 +/- 7.2 years. The cut-off level for GH response was set at 7 microg/l, according to the literature. Serum ferritin, IGF-1, liver enzymes, alkaline phosphatase (ALP) and and type1 Collagen CarboxyTelopeptide (CCT1) were also determined.

Results

We diagnosed GH deficiency (GHD) in 12 patients (40 %) and IGF-I deficiency (IGF-I SDS < -2) was diagnosed in 20 patients (67 %). Adult patients with TM had significantly decreased IGF-I concentrations and bone mineral density (BMD) at the femur neck and lumbar spine compared to normal controls. Thalassemic patients with GHD and IGF-I deficiency had significantly lower BMD T score at the lumbar spine compared to patients with normal GH and IGF-I levels. Thalassemic patients had higher serum CCT1 concentrations compared to normal controls. Peak GH levels were correlated significantly with IGF- I concentrations and IGF-I levels were correlated significantly with the height SDS (HtSDS) of thalassemic patients. Neither GH peak nor IGF-I concentrations were correlated to serum ferritin concentrations.

Conclusions

We conclude that GH status should be tested in adult thalassaemic patients especially those with short stature and/or decreased BMD. If the diagnosis of adult GHD is established, GH treatment may be considered for possible improvement of bone mineral density and heart function in thalassaemic patients.

Disclosures:

No relevant conflicts of interest to declare.
The Risk Of Recurrence In Women With Venous Thromboembolism While Using Estrogens: A Prospective Observational Cohort Study
Authors: Kyrle Paul A , Eischer Lisbeth , Eichinger Sabine
Published: October 2019

Objective

Because of the high recurrence risk, guidelines recommend indefinite anticoagulation in women with a first unprovoked proximal deep-vein thrombosis (DVT) and/or pulmonary embolism (PE). The optimal duration of anticoagulation in women who had venous thromboembolism (VTE) while using estrogens is unknown. We therefore compared the risk of recurrent VTE between women who used estrogens at the time of first VTE and women who did not.

Methods

This analysis was performed within the frame of the Austrian Study on Recurrent Venous Thromboembolism (AUREC), an on-going prospective observational study. Patients with a first objectively confirmed DVT of the leg and/or PE who had received anticoagulants for 3 to 18 months were included. Exclusion criteria were: age < 18 years; VTE associated with surgery, trauma, cancer or pregnancy; long-term anticoagulation; natural inhibitor deficiency; lupus anticoagulant; homozygosity or double heterozygosity for factor V Leiden and/or the prothrombin mutation. Women were advised to refrain from further estrogen use and were excluded in case of non-adherence. The study end point was recurrent symptomatic DVT and/or PE verified by imaging. The local ethics committee approved the study and all patients gave written informed consent.

Results

We followed 630 women (mean age 46 +/- 17 years) who had been treated with oral anticoagulants for 7 (+/- 3) months for an average of 69 (+/- 52) months. Recurrent VTE was recorded in 71 patients (11%). Recurrent VTE occurred in 22 (7%) of 333 estrogen users and in 49 (17%) of 297 non-users. After 1, 2 and 5 years, the cumulative probability of recurrence was 1% (95% CI 0-2), 1% (95% CI 0-2) and 6% (95% CI 3-9) among estrogen users and 5% (95% CI 2-7), 9% (95% CI 6-13) and 17% (95% CI 12-22) among non-users, respectively (p < 0.001, Figure). Compared to non-users, estrogen users had a relative risk (RR) of recurrent VTE of 0.4 (95% CI 0.2-0.8) after adjustment for age, site of first VTE and factor V Leiden carrier status. Compared to non-users in the respective age groups, the RR of recurrent VTE was 0.4 (95% CI 0.2-0.8) among estrogen containing contraceptive users and was 0.7 (95% CI 0.3-1.5) among women using estrogen containing hormone replacement therapy.

Conclusion

Women who had their first VTE while using estrogens have a low risk of recurrent VTE. The recurrence risk is particularly low in estrogen containing contraceptive users. We therefore propose that these women should receive anticoagulant therapy for no longer than 3 months.

Disclosures:

No relevant conflicts of interest to declare.
Packed Red Blood Cells Modulate Expression Of Dendritic Cell Signal Transduction and Antigen Presentation Pathways
Authors: Dean Melinda M , Ki Katrina , Tran Thu V , Baidya Shoma , Christensen Anne-Marie , Flower Robert L
Published: October 2019

Introduction

Clinical studies suggest packed red blood cell (PRBC) transfusion modulates recipients' immune responses, resulting in increased rates of infection, morbidity and mortality. In addition, there is evidence that increased length of storage of PRBC before transfusion is associated with worse outcomes. The mechanisms driving immunosuppression and transfusion-related poor patient outcomes remain largely undefined. As dendritic cells (DC) play a critical role in initiation and regulation of the immune response, this study investigated transfusion-mediated modulation of expression of DC genes involved in inflammation, antigen presentation and signal transduction.

Methods

Monocyte-derived DC (MoDC) were differentiated following exposure to PRBC (at either D2, D14, D28 or D42 of routine storage) in an in vitro transfusion model. Gene expression profiling of MoDC generated “post-transfusion” was assessed at each time point using quantitative real time PCR using ΔΔCT method (relative to GAPDH and matched “no transfusion control”) and data analysed using ANOVA (95% CI). Expression array (Applied Biosystems) consisted of 28 genes broadly categorised into 1) chemokines, cytokines and receptors, 2) antigen presentation, 3) signal transduction.

Results

PRBC transfusion significantly modulated expression of genes associated with signal transduction (CD86, CD44, TAP2, all p<0.05) and antigen presentation (NFκB2, RELA, RELB, all p<0.05). Modulation of gene expression was associated with the storage age of the PRBC to which the “recipient” was exposed. Networks of gene interactions were generated (Ingenuity Systems) to illustrate potential mechanisms of immune deregulation that are associated with transfusion-related DC modulation.

Conclusions

This study reports, for the first time, transfusion-driven modulation of DC gene expression that was associated with the storage age of PRBC transfused. These results provide a basis for the early assessment of immune function that we plan to translate into clinical studies to evaluate the efficacy of diagnostic tools to predict poor patient outcomes.

Disclosures:

No relevant conflicts of interest to declare.
Pleiotrophin Improves Survival Following Radiation-Induced Myelosuppression and Mediates HSC Expansion Via Induction Of Ras Signaling
Authors: Himburg Heather A , Doan Phuong L. , Quarmyne Mamle , Nakamura Mai , Chao Nelson J. , Chute John P.
Published: October 2019

Discovery of the mechanisms through which the bone marrow microenvironment stimulates hematopoietic regeneration following myelosuppression could lead to therapies to accelerate hematopoietic reconstitution in patients receiving chemotherapy, total body irradiation and stem cell transplantation. We have previously shown that treatment with pleiotrophin (PTN), a heparin-binding growth factor which is secreted by BM endothelial cells (ECs), causes a 10-fold expansion of murine long term-HSCs in culture (Himburg et al. Nat Med 2010). More recently, we demonstrated that PTN-deficient mice have a >10-fold deficit in LT-HSCs and hematopoietic regenerative capacity compared to PTN+/+ mice, suggesting an important role for PTN in maintaining the HSC pool in vivo (Himburg et al. Cell Reports 2012). In keeping with this, 100% of PTN-deficient mice died prior to day +30 following 700 cGy total body irradiation (TBI) compared to 30% mortality in irradiated, PTN+/+ mice (P<0.0001). In order to determine the therapeutic potential of PTN as a systemically deliverable agent to accelerate hematopoietic recovery following myelosuppression, we irradiated C57Bl6 mice with 700 cGy TBI followed by every other day dosing with PTN or saline through day +14. At day +30, 80% of the PTN-treated mice were alive compared to 30% survival in the irradiated, saline-treated group (P=0.03). Interestingly, systemic administration of PTN was equally effective at promoting the survival of irradiated mice when administered as late as 96 hrs post-TBI, suggesting that PTN promotes HSC regeneration after injury. Mechanistically, PTN treatment significantly decreased HSC apoptosis following ionizing radiation exposure (P=0.007), which may explain, at least in part, the mitigative effects of PTN treatment on survival from radiation injury. Furthermore, we have discovered that PTN treatment strongly induces elements of the Ras/MEK/ERK signaling cascade in HSCs, including phosphorylation of Grb2 and ERK1/2, while also increasing levels of the ERK1/2 target genes, phospho-Erf1 and Fra-1. Consistent with this finding, PTN-deficient mice have significantly decreased levels of phospho-ERK1/2 in BM HSCs, suggesting that deficient Ras/MEK/ERK signaling may explain, at least in part, the HSC deficit observed in PTN-deficient mice. Importantly, pharmacologic inhibition of Ras or MEK1/2 proteins or genetic inhibition of KRas in BM KSL cells significantly abrogated PTN-mediated expansion of BM KSL cells and CFU-GEMMs in culture (P<0.01 for total KSL cells and CFU-GEMMs). Taken together, these results suggest that PTN-mediated expansion of HSCs may be dependent upon activation of the Ras/MEK/ERK pathway and provide the basis for further studies to delineate the role of this pathway in mediating PTN effects on the HSC pool in vitro and in vivo.

Disclosures:

No relevant conflicts of interest to declare.
Myelodysplastic Syndrome-Derived Stromal Cells Support Leukemia-Initiating Cells and Contradirectly Eliminate Normal CD34+ Clonogenic Cells
Authors: Horiguchi Hiroto , Kobune Masayoshi , Kikuchi Shohei , Iyama Satoshi , Takada Kohichi , Murase Kazuyuki , Ono Kaoru , Kamihara Yusuke , Hashimoto Akari , Tatekoshi Ayumi , Hayashi Tsuyoshi , Sato Tsutomu , Miyanishi Koji , Sato Yasushi , Takimoto Rishu , Kato Junji
Published: October 2019

Introduction

The failure of normal hematopoiesis in myeloid neoplasm could be induced by a variety of mechanism. Regarding myelodysplastic syndrome (MDS)/acute leukemia (AML), aberrant hematopoietic stem/progenitor cells with exhibiting ineffective hematopoiesis and impaired differentiation ability gradually substitute it for normal hematopoietic stem/progenitor cells during a long term as a consequent of replacement of stem cell niche. However, it has not yet been clarified precise mechanism how MDS stem/progenitor cells could replace normal hematopoietic stem/progenitor cells.

Methods

In an attempt to analyze the supporting activity of bone marrow (BM) stromal cells, we first established the MDS/AML-derived stromal cells and healthy volunteer (HV)-derived-stromal cells. Next, MDS/AML-derived CD34+ cells or normal CD34+ cells were cocultured with established stromal cells using cytokines including stem cell factor, thrombopoietin, flt3-ligand in the presence of notch ligand (for normal CD34+ cells) or IL-3 (for AML/MDS derived cells). Subsequently, we analyzed clonogenic cells after 2 weeks coculture, 5 week cobblestone area-forming cells (CAFC) and repopulating cells in immunedeficient mice (NSG mice).

Results

The support of clonogenic cells after 2 weeks coculture and 5 weeks CAFCs was observed after coculture with normal CD34+ cells and HV-derived stromal cells. Furthermore, these cocultured cells engrafted into immunedeficient mice. Interestingly, the number of colony-forming units (CFU) mixed cells (MIXs) and CAFC derived from CD34+ cells was drastically reduced after coculture with MDS/AML-derived stromal cells. Nevertheless, MDS/AML-derived stromal cells support the proliferation of leukemia-initiating cells (L-ICs) and L-ICs were detected after third replating. These results indicate that MDS/AML-derived stromal cells preferentially support leukemia stem/progenitor cells, but not normal CD34+ cells. We compared the mRNA expression between (HV)-derived-stromal cells, MDS/AML-derived stromal cells and 5-aza-dC-treated stromal cells. The expression of several factors including hedgehog-interacting protein (HHIP) was reduced in MDS/AML-derived stromal cells. 5-aza-dC treatment restored the expression in some of genes and the stromal supporting activity for normal CD34+ cells partially recovered.

Conclusion

These results suggest that reduction of several gene expressions was detected in MDS/AML stromal cells by changes of methylation status. The epigenetic alteration of stromal genome may be involved in the progression of myeloid disorders.

Disclosures:

No relevant conflicts of interest to declare.
Evidence That GPI-AP-Specific CTLs Are Not Involved In The “escape” Of Piga mutant Hematopoietic Stem Cells In Aplastic Anemia
Authors: Katagiri Takamasa , Maruyama Hiroyuki , Ohtake Shigeki , Saito Chizuru , Hosokawa Kohei , Ogawa Seishi , Nakao Shinji
Published: October 2019

Background

Hematopoietic stem cells (HSCs) harboring PIGA mutations acquire a survival advantage under immune pressure compared to normal HSCs in patients with acquired aplastic anemia (AA). Cytotoxic T cells (CTLs) specific to glycosylphosphatidylinositol-anchored proteins (GPI-APs) are reportedly involved in this survival advantage, because PIGA mutant HSCs cannot present GPI-AP-derived peptides via class I HLAs. However, there is no convincing evidence that CTLs specific to GPI-AP-derived peptides are involved in the “escape” hematopoiesis by PIGA mutant HSCs. We recently demonstrated that 31.4-99.4% HLA-A allele-lacking leukocytes (HLA-LLs) were detectable in approximately 13% of AA patients as a result of escape hematopoiesis by HSCs with uniparental disomy in the short arm of chromosome 6, and that some patients possessed both GPI-AP-deficient (GPI-AP-) leukocytes and HLA-LLs (Katagiri, et al. Blood 2011). We hypothesized that if GPI-AP-derived peptides serve as a target for CTLs that elicit the development of AA, HLA-LLs may always be detectable only in the GPI-AP+ leukocyte population, because PIGA mutant HSCs do not require the lack of HLA class Is for the escape from the attack by GPI-AP peptide-specific CTLs.

Objectives and Methods

To examine this hypothesis, the GPI-AP expression was analyzed in various leukocyte lineages in 32 (nine at diagnosis and 23 previously treated) AA patients possessing HLA-LLs by a flow cytometry (FCM) analysis with liquid fluorescent aerolysin.

Results

A total of 0.01%-50% GPI-AP- granulocytes (GPI-AP- Gs) were detected in 22 (69%) of the 32 HLA-LLs (+) patients. Of the 22 patients possessing both HLA-LLs and increased GPI-AP- Gs, HLA-LLs were detectable in GPI-AP+ cells alone in 19 patients (86%). However, in the remaining three patients, HLA-LLs were shown in both GPI-AP+ and GPI-AP- populations. To determine which mutation occurs first in HSCs with a PIGA mutation and 6pUPD, the lineage diversity of GPI-AP- HLA-LLs was determined in the three patients. In two of the three patients, the lineage diversity of GPI-AP- cells (G/monocytes (M)/T cells (T)/B cells (B)/NK cells (NK)) and G/M/T) was greater than that of the HLA-A-lacking cells (G/M/B/NK and G/M) suggesting that PIGA mutations occurred earlier in the maturation of HSCs than did 6pUPD. The lineage diversity was the same in the GPI-AP- cells and HLA-LLs in one patient

Conclusions

The presence of HLA-LLs in the GPI-AP- leukocyte population and lower lineage diversity in HLA-LLs than GPI-AP- leukocytes suggest that CTLs specific to GPI-APs are not involved in the escape of PIGA mutant HSCs in AA, and that other mechanisms, such as a lower sensitivity to myelosuppressive cytokines than wild-type HSCs, may contribute to the survival advantage of PIGA mutant HSCs.

Disclosures:

No relevant conflicts of interest to declare.
Ikaros Mutation Confers Integrin-Dependent Survival Of Pre-B Cells and Progression To Acute Lymphoblastic Leukemia
Authors: Jena Nilamani , Joshi Ila , Yoshida Toshimi , Qi Xiaoqing , Zhang Jiangwen , Georgopoulos Katia , Van Etten Richard A.
Published: October 2019

Deletion of the IKAROS DNA-binding domain generates dominant-negative isoforms that interfere with the transcriptional activity of the IKAROS family and correlate with poor prognosis in human precursor B cell acute lymphoblastic leukemias (B-ALL). In this study, we defined the role of the Ikaros family during pre-B cell differentiation, the stage from which human B-ALLs arise, by conditionally inactivating IKAROS DNA binding in the immediate precursors of pre-B cells in mice. We demonstrate a novel niche-dependent phase in early pre-B cell differentiation that supports self-renewal and proliferative expansion. Expression of dominant-negative IKAROS arrests cells in this state by augmenting integrin and MAPK signaling and attenuating pre-B cell receptor signaling and differentiation. Up-regulated genes in Ikaros mutant pre-B cells were highly enriched in pathways involved in focal adhesion and remodeling of the actin cytoskeleton. The mutant pre-B cells had increased β1 integrin-mediated adhesion and elevated levels of activated focal adhesion kinase (FAK), whereas treatment with a small molecule FAK inhibitor greatly reduced pre-B cell stromal adhesion and selectively induced apoptosis in Ikaros mutant but not WT pre-B cells. Transplantation of polyclonal Ikaros mutant pre-B cells into recipient mice resulted in long-latency oligoclonal pre-B-ALL, demonstrating that loss of IKAROS contributes to multistep B-leukemogenesis. The highly proliferative and aberrantly self-renewing phenotype of Ikaros-deficient pre-B cells illuminates mechanisms underlying human IKAROS mutant B-ALL and suggests new therapeutic strategies for treatment of this aggressive leukemia.

Disclosures:

Van Etten: Bristol Myers Squibb: Consultancy; Deciphera Pharmaceuticals: Consultancy; TEVA Pharmaceuticals: Consultancy, Research Funding.
The Acute Promyelocytic Leukemia-Oncoprotein PML-Raralpha Blocks Senescence and Disrupts The Atrx/Daxx Chromatin Remodeling Complex To Promote Leukemia
Authors: Korf Katharina , Wodrich Harald , Haschke Alexander , Evans Ron M. , Sternsdorf Thomas M.
Published: October 2019

Although Acute Promyelocytic Leukemia (APL) has become a curable disease due to in-depth understanding of the underlying molecular processes, its investigation has provided unique and valuable insights into the processes involved in leukemogenesis. Therefore we use it as a model disease. 99% of APL-patients express a PML-RAR fusion protein. While involvement of RAR has proven indispensable for oncogenicity, the role of the PML domain is far less clear. In our previous study (Sternsdorf et al., Cancer Cell, 2006) we found that substitution of PML with heterologous self-interaction domains suffices to induce leukemias, but drastically decreases oncogenic potency of the resulting fusion proteins. In this study, we have chosen the inverse strategy: we have modified the PML domain to create a more active artificial model oncoprotein by adapting PR to its biological environment: As the typical model organism for APL studies is the mouse, we have replaced the human PML domain with the murine PML domain. This oncoprotein (mPR) creates APL-type leukemias in mice with higher penetrance and shorter latency than its human counterpart, hPR. We have used this system to study immediate early effects of expression of the model oncoprotein.

While proliferating murine bone marrow cells go into senescence ex vivo, expression of mPR prevents this and robustly immortalizes murine bone marrow from every mouse strain tested so far. Senescence-associated upregulation of the cell-cycle regulators p21 and p19 was efficiently blocked by mPR expression. In mouse cells, mPR exhibits higher potency in disrupting the PML-associated Daxx/ATRX complex than hPR. Knockdown of ATRX, but not Daxx ameliorated ATRA-induced growth suppression and p21 upregulation in the human APL model cell line NB4. These data suggest, that PML-RAR promotes leukemogenesis by disrupting the Daxx/ATRX complex, which assembles at PML nuclear bodies during the onset of senescence.

Disclosures:

No relevant conflicts of interest to declare.
Dual PI3K/Akt/mTOR Pathway Inhibitor Potentiate Cytarabine Cytotoxicity For Acute Myeloid Leukemia
Authors: Kim Eun Kyung , Jin Kang Hyoung , Kim Hyung Joon , Lee Ji Won , Kim Hyery , Park Kyung Duk , Shin Hee Young , Ahn Hyo Seop
Published: October 2019

Phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signal transduction pathway integrating signals from multiple receptor tyrosine kinases has been firmly established as a major determinant for cell growth, proliferation, and survival in a wide array of solid cancers. PI3K/Akt/mTOR pathway is frequently activated in acute myeloid leukemia (AML) cells and contributes to survival and drug-resistance of AML through various mechanisms. BEZ235 is one of the most promising dual inhibitor of PI3K and mTOR currently under clinical development in solid tumor area. In this study, the potential of BEZ235 was investigated as antileukemic agent using alone or with cytarabinearabinoside (AraC) as combination regimen.

AML cell lines KG-1, MV 4-11, THP-1 and HL60 were treated with AraC, BEZ235 and combination regimen with various mixed ratio. BEZ235 effectively inhibited leukemic cell growth with similar range of half maximal inhibitory concentration (IC50) values among different cell lines. Apoptosis was induced gradually as BEZ235 concentration increased, but significant level of apoptosis was not shown even at higher concentration beyond IC50 value. Then, AraC-resistant MV4-11 and THP-1 cell lines were chosen to investigate interaction between BEZ235 and AraC. Using CalcuSyn software based on Chou and Talalay analysis, Combination Index (CI) value was calculated in each combination regimen. Moderate to strong synergism was shown and it was well maintained as combination ratio of AraC versus BEZ235 gradually decreased from 20:1 to 1,000:1. BEZ235 reduced resistance to AraC when it was added as combination regimen, and significance of combination effect changed according to AraC concentration. When antileukemic effect was compared among combination regimens with different schedules, synergism was maximized when BEZ235 was pretreated before AraC administration. This means BEZ235 sensitizes leukemic cells to apoptotic effect of AraC.

Genetic alteration in PI3K/Akt/mTOR pathway is an attractive target to investigate and dual pathway inhibitor BEZ235 has potential to maximize AML treatment through sensitization of leukemic cells to conventional drug. The results of this experiment suggest the possibility of designing early clinical trials for the therapy - AraC administration after dual inhibitor BEZ administration. An effective control of a signal transmission system using innovate new drugs along with an accurate understanding of a signal transmission system which is the target of therapy will establish a foothold for the development of AML therapy.

Disclosures:

No relevant conflicts of interest to declare.
Molecular and Cytogenetic Risk Stratification For Core-Binding Factor-Positive Adult AML With Analysis Of Post-Remission Treatment Outcomes Including Transplantation
Authors: Yoon Jae-Ho , Kim Heeje , Shin Seung-Hwan , Jeon Young-Woo , Kim Jung-Ho , Lee Sung-Eun , Cho Byung-Sik , Eom Ki-Seong , Kim Yoo-Jin , Lee Seok , Min Chang-Ki , Cho Seok-Goo , Kim Dong-Wook , Lee Jong-Wook , Min Woo-Sung , Park Chong-Won
Published: October 2019

Core-binding factor (CBF)-positive acute myeloid leukemia (AML) is regarded as a favorable group with good complete remission (CR) rate after induction chemotherapy and is generally treated by repeated high-dose cytarabine consolidation or autologous hematopoietic stem cell transplantation (auto-HSCT). However, emerging molecular studies have recently identified the unfavorable CBF-AML subgroup which should be treated by further intensified treatments.

This single center retrospective study enrolled 264 adult CBF-AML patients from 2002 to 2011. Except 15 patients, 217 patients were treated by intensive induction chemotherapy and 32 were treated by reduced intensity treatment. After CR achievement, patients with available donor were treated by allogeneic (allo)-HSCT and the rest were treated by auto-HSCT or chemotherapy alone. We evaluated 206 patients who achieved CR after intensive chemotherapy regarding survival outcomes according to post-remission therapies and prognostic factors which affected the outcomes. The factors included cytogenetic study and subgroup analysis with additional chromosomes and normal karyotype (NK) mosaicism, c-kit mutation, minimal residual disease (MRD) qPCR level, BAALC and WT1 expression.

We achieved CR in 94.9% with intensive chemotherapy and 115 patients went on allo-HSCT and 72 were treated by auto-HSCT. There were no significant OS differences between CBF¥â/MYH11 and RUNX1/RUNX1T1 (p=0.173), and auto-HSCT showed favorable EFS (p=0.038) compared to allo-HSCT and chemotherapy alone. For cytogenetic analysis, inv(16) or t(16;16) with NK mosaicism showed the most favorable OS compared to t(8;21) with additional chromosome (¡Ã2) which showed the worst OS. c-kit mutation was a poor prognostic factor with lower reduction rate of post-induction MRD qPCR, however the effect was not definite after HSCT. For HSCT patients, we analyzed post-HSCT MRD qPCR and WT1 expression level. We found that undetected level of post-HSCT MRD qPCR and lower level of WT1 expression (<0.015) showed the most favorable OS with no relapse cases.

For CBF-AML, the role of auto-HSCT and allo-HSCT for selected patients should be re-evaluated by large prospective studies and the values like post-treatment MRD qPCR and WT1 expression level can be used for prediction of patients who might relapse with higher probability.

Disclosures:

No relevant conflicts of interest to declare.
Multi-Virus-Specific T-Cell Therapy For Patients After Hematopoietic Stem Cell and Cord Blood Transplantation
Authors: Hanley Patrick , Leen Ann , Gee Adrian P. , Leung Kathryn , Martinez Caridad , Krance Robert A. , Liu Hao , Brenner Malcolm K. , Heslop Helen E. , Rooney Cliona M. , Bollard Catherine M.
Published: October 2019

Cytomegalovirus, EBV and adenovirus are particularly problematic in patients after hematopoietic stem cell (HSCT) and cord blood transplantation (CBT) and are associated with significant morbidity and mortality. Deficiencies in conventional therapeutics have increased interest in an immunotherapeutic approach to viral disorders. We have developed two strategies to grow multivirus-specific donor-derived T-cells from peripheral blood (PB) and naive cord blood (CB). Using an adenoviral-vector expressing CMVpp65 to modify monocytes, DC and EBV-LCL we generated a single culture of PB or CB mononuclear cells that gave rise to multivirus-specific cytotoxic T-cells (CTL)(n=76). We have infused 34 patients with PB-derived CTL and 8 patients with CB-derived CTL. Patients received CTL infusions from 35 to 164days (median 84d) post HSCT or CBT at a median of 5x10e7 cells/m2. None developed >grade II GvHD or other toxicities over 3 months of safety monitoring after infusion. We observed up to a 5-fold increase in CMV- and EBV-specific T-cells by 4weeks post-CTL as measured by IFN-g ELISPOT assay. 33 viral reactivations were observed in patients before or immediately after CTL infusion. In the absence of conventional therapy, 8 of the 11 patients with CMV infection became negative for CMV in the blood within 7d of CTL infusion, with a corresponding rise in CMV-specific CTL in PB. Each of 10 patients with high EBV loads cleared their virus, as did 11 of 12 patients with adenoviral infections/disease. This study demonstrates that multivirus-specific CTL derived from the PB of seropositive donors as well as the CB of virus naive donors expand in vivo and are active against multiple viruses. Furthermore, by restoring immunity to multiple viruses simultaneously, the need for continued prophylaxis with pharmacotherapy is eliminated, thus, improving the efficiency and cost effectiveness of protecting HSCT and CBT recipients from these potentially lethal viruses.

Disclosures:

No relevant conflicts of interest to declare.
Pediatric Fanconi Anemia With Secondary AML: A Retrospective Outcome Report From The German AML-BFM Group
Authors: Beier Rita , Hoseini Sayed , Maecker-Kolhoff Britta , Schneppenheim Reinhard , von Neuhoff Christine , Ebell Wolfram , Schmid Hansjörg , Bader Peter , Ehlert Karoline , Sykora Karl-Walter , Creutzig Ursula , Kratz Christian , Chao Mwe Mwe , Reinhardt Dirk , Sauer Martin G.
Published: October 2019

Background

To date, allogeneic stem cell transplantation (SCT) is the only curative approach for patients with Fanconi anemia (FA) and myeloid malignancy (AML). No data exist on whether cytoreductive chemotherapy prior to SCT impacts outcome.

Methods

We retrospectively analyzed data retrieved from the AML-BFM database (Germany) regarding children with FA and AML.

Results

Between January 1993 and May 2013 14 patients were identified, in whom AML was diagnosed at a median age of 11.6 yrs [0.9-19.6] (n=13). In 10 patients (4 not available) the diagnosis FA preceded the occurrence of AML by a median of 32.3 months [0-161].

Six of 14 patients underwent SCT achieving a 5 year overall survival of 42%. Median time to transplant after the diagnosis of AML was 2 months. One patient died after relapse, one due to severe graft versus host disease (GvHD), another of unknown cause. Of the three surviving patients two had chronic GvHD (one limited, one extended). All three surviving patients received a radiation free preparative regimen (1. fludarabine (Flu) and cyclophosphamide (Cy); 2. busulfan (Bu) and Flu; 3. Bu, Flu and Cy.) including antibodies for intensive GVHD prophylaxis. In all three cases a high cell dose of either PBSC (30.1 x 10e6 CD34+) or BM (2.13 and 3.43 x 10e8 MNC) was infused. Two surviving patients received low dose cytoreductive therapy (thioguanin and cytarabin) to bridge time to SCT. The remaining patient did not receive pre-transplant therapy.

Eight of 14 patients did not receive a SCT. Median survival for these children was 40 days. Three of 8 patients received low intensity chemotherapy (thioguanin and/or cytarabin). Two were treated with more intensive combinations (e.g. cytarabin, adriamycin and etoposide). The latter all died of complications from long lasting aplasia.

Additionally to the 14 patients described above, another patient was identified, in whom AML developed 14 months after successful SCT for bone marrow failure. Blasts were of recipient origin and the patient died of progressive disease.

Conclusion

The data presented are subject to selection bias. Three of 14 patients survived and 2/3 surviving patients received low dose cytoreductive therapy for disease control before going to transplant. None of them achieved complete remission (CR) before SCT. Graft failure and chronic GVHD were the main complications after transplantation. FA patients with AML should proceed to SCT. Mild cytoreductive therapy with thioguanine and cytarabine may be useful. Achieving CR pre transplant might not be necessary for OS.

Disclosures:

No relevant conflicts of interest to declare.
Second Bacteremia During Antibiotic Treatment In Children With Acute Myeloid Leukemia: A Report From The Canadian Infections In AML Research Group
Authors: Tran Thai Hoa , Yanofsky Rochelle , Johnston Donna , Dix David , Gillmeister Biljana , Ethier Marie-Chantal , Portwine Carol , Price Victoria E. , Mitchell David , Cellot Sonia , Lewis Victor A. , Zelcer Shayna , Silva Mariana , Michon Bruno , Bowes Lynette , Stobart Kent , Brossard Josee , Beyene Joseph , Sung Lillian
Published: October 2019

Background

The risk of second bacteremia during antibiotic treatment for initial bacteremia is unknown in high-risk populations. Objectives were to describe the prevalence of second bacteremia during treatment and identify risk factors in children with acute myeloid leukemia (AML).

Methods

We conducted a retrospective, population-based cohort study that included children and adolescents with de novo, non-M3 AML who were diagnosed and treated between January 1, 1995 and December 31, 2004 at 15 Canadian centers. Patients were monitored for bacteremia during chemotherapy until completion of treatment, hematopoietic stem cell transplantation, relapse, refractory disease, or death.

Results

There were 290 episodes of bacteremia occurring in 185 (54.3%) of 341 children. Eighteen (6.2%) had a second bacteremia while receiving antibiotic treatment. Two episodes of second bacteremia were complicated by sepsis; there were no infection-related deaths. Eleven episodes (61.1%) had either an initial Gram-positive and subsequent Gram-negative bacteremia or initial Gram-negative followed by Gram-positive bacteremia. Days receiving corticosteroids (odds ratio (OR) 1.09, 95% confidence interval (CI) 1.07-1.12; P<0.0001), cumulative dose of corticosteroids (OR 1.04, 95% CI 1.00-1.08; P=0.035) and days of neutropenia from start of course to initial bacteremia (OR 1.07, 95% CI 1.02-1.12; P=0.007) were significantly associated with second bacteremia.

Conclusion

In pediatric AML, 6% will experience a second bacteremia during antibiotic treatment; duration of corticosteroid exposure and neutropenia are risk factors. These patients remain at high risk for second bacteremia after identification of the initial bacteremia and warrant continued broad-spectrum treatment during profound neutropenia.

Abbreviations

CONS: coagulase negative Staphylococcus ; VGS: viridans group Streptococcus; Amp: ampicillin; Cz: ceftazidime;

Cef: cefotaxime; Cipro: ciprofloxacin; Clin: clindamycin; Clox: cloxacillin; G: gentamicin; Metro: metronidazole; Mero: meropenem;

O: oxacillin; Pip: piperacillin; Ta: piperacillin/tazobactam; Tm:ticarcillin/clavulanate; To: tobramycin; V: vancomycin.

Disclosures:

No relevant conflicts of interest to declare.
Inhibition Of Inflammation Driven Leukemia Stem Cell Self-Renewal With a Selective JAK2 Antagonist
Authors: Court Recart Angela C , Sadarangani Anil , Chun Elizabeth , Mason Cayla N , Jiang Qingfei , Barrett Christian L , Wall Russell , Goff Daniel J , Geron Ifat , Shih Alice , Leu Heather S. , Ma Wenxue , Minden Mark D. , Frazer Kelly A , Marra Marco A. , Crews Leslie A , Jamieson Catriona HM
Published: October 2019

Chronic myeloid leukemia (CML) represents an important paradigm for identifying the molecular events that promote malignant reprogramming of progenitors into therapeutically recalcitrant leukemia stem cells (LSC) during blast crisis (BC) transformation. To elucidate mechanisms of human BC LSC generation, whole transcriptome RNA sequencing (RNA Seq), lentiviral BCR-ABL and JAK2 transduction, quantitative RT-PCR (qRT-PCR) and serial xenotransplantation studies were performed. In human BC LSC, RNA seq revealed extensive upregulation of inflammation-responsive genes in conjunction with JAK/STAT signaling pathway activation and splice isoform specific qRT-PCR uncovered a predilection for selective STAT5a isoform expression. While lentiviral BCR-ABL1 expression in cord blood progenitors enhanced JAK2 activation and expression of specific STAT5a splice isoforms, lentiviral human JAK2 overexpression globally activated inflammation-response genes and expression of adenosine deaminase RNA associated (ADAR1), a primate specific RNA editase previously shown to activate self-renewal in response to inflammation. Notably, inhibition of BC LSC self-renewal with dasatinib, a BCR-ABL inhibitor, combined with a potent JAK2 inhibitor, SAR302503, was associated with reduced STAT5a isoform expression and phospho-STAT5 activation as well as ADAR1 expression and activity. These results highlight a novel JAK/STAT pathway driven niche-responsive mechanism of human BC LSC generation that can be targeted, at least in part, with a selective JAK2 inhibitor and may be utilized as an RNA editing-based biomarker of cancer stem cell generation and therapeutic resistance.

Disclosures:

Jamieson: Sanofi: Consultancy.
Impaired Osteogenic Differentiation Of Mesenchymal Stem Cells Derived From Bone Marrow Of Patients With Low-Risk Myelodysplastic Syndromes
Authors: Chang Chunkang , Fei Chengming , Zhao Youshan , Guo Juan , Li Xiao
Published: October 2019

Background

The pathogenesis of MDS has not been completely understood, and insufficiency of the hematopoietic microenvironment can be an important factor. MSCs and osteoblasts are key components of the hematopoietic microenvironment. Studying osteoblastic differentiation of MSCs quantitatively may help to understand the pathogenesis of MDS.

Methods

38 patients with MDS and 15 normal donors were investigated in this study. Osteoblastic differentiation assays were performed in 16 MDS cases and 8 controls. The expression of osteogenic differentiation markers were measured by real-time PCR. Alkaline phosphatase staining was performed with Alkaline Phosphatase staining kit after 3,7,14 days of incubation. ALP activity was assessed at 3, 7, and 10 days after osteogenic differentiation. Mineralization analysis was performed at 7, 14 and 21 days of osteogenic induction. The areas of mineralization were measured by Image-Pro Plus 6.0 software.

Results

Both MDS-MSCs and normal cells displayed same fibroblast-like morphology and similar antigen expression. The expression level of RUNX2 was significantly decreased in MSCs from MDS, compaired with normal controls, especially in lower-risk MDS. After osteogenic induction, lower-risk MDS showed lower alkaline phosphatase activity, less intense alizarin red S staining, and lower gene expression of osteogenic differentiation markers, however, higher-risk MDS was normal.

Conclusions

We concluded that impaired osteogenic differentiation of MSCs was seen mainly in patients with lower-risk MDS. It may contribute to the ineffective hamatopoiesis of MDS.

Disclosures:

No relevant conflicts of interest to declare.
Spatial Epidemiology Of Chronic Lymphocytic Leukemia and Small Lymphocytic Lymphoma In The State Of Georgia
Authors: Bulka Catherine , Nastoupil Loretta J. , Switchenko Jeffrey , Ward Kevin , Bayakly Rana , Waller Lance , Flowers Christopher R.
Published: October 2019

Background

Exploring spatial patterns of disease incidence allows for the identification of areas of elevated or decreased risk. For chronic lymphocytic leukemia and small lymphocytic leukemia (CLL/SLL), which have poorly understood etiologies, identifying spatial patterns through cluster analysis may provide insight about potential environmental and socio-demographic risk factors.

Methods

In order to investigate the spatial patterns of CLL/SLL incidence among adults (≥ 20 years), we linked cancer incidence data for the period 1999-2008 from the Georgia Comprehensive Cancer Registry (a CDC-supported a statewide population-based cancer registry collecting all cancer cases diagnosed among Georgia residents since 1995) with population data from the 2000 U.S. Census. CLL/SLL cases were aggregated to the census tract level. CLL/SLL incidence in Georgia was standardized indirectly by age, sex, and race to national rates obtained from SEER*Stat software. Choropleth maps were created to depict the ratio of observed to expected incidence (standardized incidence ratios [SIR]) by census tract using ArcGIS. Spatial Empirical Bayes smoothing was performed on the SIR values using GeoDa 1.01. To assess spatial correlation of SIRs, we conducted global and local cluster analyses by calculating global Moran’s I and local Moran’s I (also known as Local Indicators of Spatial Autocorrelation [LISA]) values. Cluster analyses were repeated, stratifying by age (20-59 years, 60+ years), sex, and race (Caucasian and African American). P-values less than 0.01 were considered statistically significant.

Results

765 incident CLL/SLL cases occurred among adults residing in Georgia between 1999 and 2008 (Table 1). There was a positive spatial autocorrelation for cases of CLL/SLL age 60 and older indicating these cases were geographically clustered (p = 0.0010) (Table 2). The LISA cluster map of the smoothed standardized incidence ratios shows the locations of “hot-spots” (high-high clusters) and “cold-spots” (low-low clusters) with clustering of high smoothed SIRs was found in the metro-Atlanta area, Albany, Macon, and outside of Augusta while cold-spots were mostly in the southern region of the state.

Conclusions

Despite the low number of cases of CLL/SLL in Georgia during the 10-year period studied, we found evidence of spatial clustering among adults 60 years and above. Hot-spots of smoothed SIRs were located in the metro-Atlanta area, Albany, Macon, and near Augusta, but these varied when stratified by age, sex, and race, suggesting confounding or effect modification that warrants further investigation.

Disclosures:

Flowers: Spectrum: Research Funding; Celgene: Consultancy, Research Funding; Millennium/Takeda: Consultancy, Research Funding; Genentech BioOncology: Consultancy; Sanofi: Research Funding; Janssen: Research Funding; Abbott: Research Funding.
Cost Analysis Of Stem Cell Transplantation In Developing Countries: Experience Of a Single Public Center In Mexico
Authors: León-Rodríguez Eucario , Guzmán-Uribe Patricia , Pérez-Álvarez Sandra Ileana , Cortina-Pastor Isabel
Published: October 2019

Introduction

Hematopoietic stem cell transplantation (HSCT) has become an important strategy for treatment of several diseases. However, in developing countries access is often limited by socioeconomic factors. The information about the costs of the procedure in Mexico is scarce which limits the development of public policies in the area.

Objective

Describe overall costs of HSCT as well as specific costs of resources used in a tertiary care center in Mexico City.

Material and Methods

Retrospective, descriptive, observational study. We calculated the median overall cost per transplant in the first 30 days and the median cost per resource category, using SPSS version 17.

Results

We evaluated a total of 50 TCPH from June 2010 to December 2012. Of all the procedures, 68% were autologous. The median cost for allo-HSCT was $ 24.910 USD, while for auto-HSCT was $14.742 USD. Specific charges were divided into the following areas: for allo-HSCT, conditioning chemotherapy and mobilization: $ 4.087 USD, hospitalization: $ 8.130 USD, laboratory studies: $ 3.922 USD, imaging: $ 1.012 USD, other medications: $ 5.278 USD, blood bank: $ 2.478 USD. For auto-HSCT, conditioning-mobilization: $ 4.997 USD, hospitalization $ 4.086 USD, laboratory $ 1.612 USD, imaging: $ 411 USD, other medications: $ 3.024 USD, blood bank: $ 611 USD. Estimated 5 year-overall survival for these patients was 71.6%.

Conclusions

These results contribute to the scarce information regarding costs of HSCT in our country. The cost of HSCT in INCMNSZ (government institution) is 10 times lower than in the U.S. with similar results regarding overall survival. These facts highlight the important role of non-profit institutions that contribute to the development of these programs.

Disclosures:

No relevant conflicts of interest to declare.
Systematic Review and Individual Patient Data Meta-Analysis Of Treatment-Related Risk Of Secondary Malignant Neoplasms After Hodgkin Lymphoma
Authors: Franklin Jeremy , Eichenauer Dennis A. , Becker Ingrid , Engert Andreas
Published: October 2019

Introduction

Secondary malignant neoplasms (SMN) are a major late effect of treatment for Hodgkin lymphoma (HL). Single trials have inadequate power to detect differences in SMN rates, while the many large-scale cohort-based studies of SMN after HL suffer from non-randomised, potentially biased comparisons of treatment strategies. The consequences of choice of first-line treatment for SMN risk remain unclear. We performed a Cochrane systematic review addressing this question based on our previous such review in 2000-2004.

Material and methods

Individual patient data (IPD) were collected from randomised controlled trials testing 5 currently relevant experimental strategies: avoidance of additional radiotherapy (RT) after chemotherapy (CT); reduction of RT field; reduction of RT dose; use of fewer CT cycles; intensification of CT regimen. All trials employed modern ABVD-like regimens and limited radiation fields, and recruited at least 50 patients per treatment group. Incidence of SMN, overall survival (OS) and progression-free survival (PFS) were analysed. Due to small numbers of events, SMN was analysed using Peto’s method.

Results and Discussion

Data from 16 of the 21 eligible trials were obtained, including 9498 patients. These trials recruited between 1984 and 2007 and randomised between 100 and 1351 patients each. Standard chemotherapy was predominantly ABVD, followed by COPP/ABVD and MOPP/ABV. Most frequent intensified chemotherapies were escalated BEACOPP and Stanford V. For each study question, key information and resulting odds ratios are shown in the table. Avoidance of additional RT significantly reduced the SMN risk (Peto odds ratio 0.433, 95% confidence interval (0.28; 0.82), p=0.010). Intensified chemotherapy regimens were associated with a consistent slightly higher risk but the effect was not significant. Other study questions showed no marked effects on SMN risk. Regarding solid tumors, follow-up is still too short: an update after 5 to 10 years is necessary.

Disclosures:

No relevant conflicts of interest to declare.