GLORIA

GEOMAR Library Ocean Research Information Access

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
Material
Language
  • 1
    In: Blood, American Society of Hematology, Vol. 104, No. 11 ( 2004-11-16), p. 1228-1228
    Abstract: In murine BMT systems, the administration of palifermin reduces small bowel damage and serum systemic inflammatory mediators resulting in less clinical aGVHD while preserving graft-vs-leukemia and improving leukemia free survival. We initiated a phase I schedule escalation trial of palifermin plus standard aGVHD prophylaxis (tacrolimus and 5 mg/m2 methotrexate on days 1, 3, 6, and 11) in patients with an unrelated or HLA mismatched donor who are at high risk for developing aGVHD. All study patients (n=35) had high risk hematologic malignancies and received a fully myeloablative conditioning regimen. Palifermin (60 mcg/kg/day intravenously) was administered for 3 consecutive days prior to the conditioning regimen, and then for 3 consecutive days each week starting Day 0, escalating by 6 doses per cohort, to a maximum of 36 doses. There were 6 cohorts, and each cohort had at least 2 patients. Dose schedules were escalated to the next cohort as long as the dose limiting toxicity (DLT) rate for the current cohort was less than 20% as determined by statistical analysis using a modified form of the continual reassessment method. A DLT was defined as any grade 3 or 4 nonhematologic toxicity that was possibly, probably, or definitely related to palifermin occurring within 14 days of receiving the final dose of palifermin. Nine DLTs were observed (table), and all patients were fully evaluable for aGVHD. In 20 patients, palifermin was not administered through engraftment—three patients completed palifermin prior to engraftment by protocol design (early cohorts), eight patients were removed from study due to DLTs, and nine patients discontinued palifermin by preference of either patient or physician. In this group of 20, 7 (35%) developed grade 3–4 aGVHD. In the other group of 15 patients, palifermin was administered through the time of neutrophil engraftment and only 3 (20%) developed grade 3–4 aGVHD. Mortality at 100 days for subjects who did not receive palifermin through engraftment was 30±10% compared to14±9% for patients who received palifermin through engraftment (p=NS). When adjusted for the interaction of palifermin administration with the number of methotrexate doses given (1–2 vs. 3–4), administration of palifermin through the time of engraftment was associated with improved survival (p = 0.02). Disease status at time of transplant (advanced vs non-advanced) and degree of HLA disparity (5/6 vs 6/6) did not alter the association. These preliminary data suggest that the administration of palifermin through the time of engraftment possibly has a survival benefit in patients at high risk for acute GVHD, perhaps mediated through an interaction with methotrexate. Dose Limiting Toxicities Toxicity # of patients # of palifermin doses Rash (gd 3) 4 2, 6, 6, 6 Hand-foot reaction (gd 3) 2 7, 9 Elevated amylase (gd 4) 1 3 Dyspnea (gd 3) 1 15 Hypoxia (gd 3) 1 15
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2004
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    In: Blood, American Society of Hematology, Vol. 103, No. 6 ( 2004-03-15), p. 2417-2426
    Abstract: Idiopathic pneumonia syndrome (IPS) is a major complication after allogeneic bone marrow transplantation (allo-BMT) and involves the infiltration of donor leukocytes and the secretion of inflammatory cytokines. We hypothesized that leukocyte recruitment during IPS is dependent in part upon interactions between chemokine receptor 2 (CCR2) and its primary ligand monocyte chemoattractant protein–1 (MCP-1). To test this hypothesis, IPS was induced in a lethally irradiated parent → F1 mouse BMT model. Compared with syngeneic controls, pulmonary expression of MCP-1 and CCR2 mRNA was significantly increased after allo-BMT. Transplantation of CCR2-deficient (CCR2-/-) donor cells resulted in a significant reduction in IPS severity compared with transplantation of wild-type (CCR2+/+) cells and in reduced bronchoalveolar lavage (BAL) fluid cellularity and BAL fluid levels of tumor necrosis factor–α (TNF-α) and soluble p55 TNF receptor (sTNFRI). In addition, neutralization of MCP-1 resulted in significantly decreased lung injury compared with control-treated allogeneic recipients. Experimental data correlated with preliminary clinical findings; patients with IPS have elevated levels of MCP-1 in the BAL fluid at the time of diagnosis. Collectively, these data demonstrate that CCR2/MCP-1 interactions significantly contribute to the development of experimental IPS and suggest that interventions blocking these receptor-ligand interactions may represent novel strategies to prevent or treat this lethal complication after allo-BMT.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2004
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    In: Blood, American Society of Hematology, Vol. 128, No. 22 ( 2016-12-02), p. 509-509
    Abstract: No laboratory test can predict non-relapse mortality (NRM) after hematopoietic cellular transplantation (HCT) prior to the onset graft-versus-host disease (GVHD). Recently, we have shown that a signature of three GVHD plasma biomarkers (TNFR1, ST2, and REG3α) can predict response to GVHD therapy and NRM at the onset of clinical GVHD (Levine, Lancet Haem, 2015). Our goal in the current study was to identify a blood biomarker signature that could predict lethal GVHD and six-month NRM well in advance of the onset of GVHD symptoms. Patient samples on day +7 after HCT were obtained from 1,287 patients from 11 HCT centers in the Mount Sinai Acute GVHD International Consortium (MAGIC). Samples from two large centers (n = 929) were combined and randomly assigned to a training set (n = 620) and test set (n = 309). 358 patients from nine others centers constituted an independent validation set. The overall cumulative incidences of 6-month NRM were 11%, 12%, and 13% for the training, test, and validation sets respectively. The incidence of lethal GVHD, defined as death without preceding relapse while under steroid treatment for acute GVHD, were 18%, 24%, and 14% in the same groups, respectively. The median day of GVHD onset was 28 days in the training set and 29 days in the test and validation sets. We measured four GVHD related biomarkers [ST2, REG3α, TNFR1, and IL2Rα] in all samples and used the training set alone to develop competing risks regression models that used all 13 possible combinations of one to four biomarkers to predict 6-month NRM. The best algorithm, which we rigorously confirmed through Monte Carlo cross-validation of 75 different combinations of training sets, included ST2 and REG3α. No combination of one, three, or four biomarkers was superior to the combination of these two biomarkers. The day 7 algorithm identified high risk (HR) and low risk (LR) groups with 6-month NRMs of 28% and 7%, respectively (p 〈 0.001) (Fig 1A). The relapse rates did not differ between risk groups so that overall survival (OS) was 60% for HR and 84% for LR (p 〈 0.001) (Fig 1B). When applied to the test set (Fig 1C/D), the algorithm identified 54/309 (17%) of the patients as HR with an NRM of 33% vs 7% for LR patients (p 〈 0.001) and 6-month OS of 57% and 81% for HR and LR patients, respectively (p 〈 0.001). In the independent validation set (Fig 1 E/F), the algorithm identified 72/358 (20%) of the patients as HR with an NRM of 26% vs 10% for LR patients (p 〈 0.001) and OS of 68% and 85% for HR and LR patients, respectively (p 〈 0.001). High risk patients were three times more likely to die from GVHD than LR patients in each cohort (p 〈 0.001) (Fig 2). The GI tract is the GVHD target organ that is most resistant to treatment and represents a major cause of NRM, and we observed twice as much severe GI GVHD (stage 3 or 4) in HR patients as in LR patients (p 〈 0.001, data not shown). The algorithm successfully separated HR and LR strata for 6 month NRM in several groups with differing risks for GVHD and NRM, including donor type, degree. of HLA-match, age group, and conditioning regimen intensity (Fig 3). In conclusion, we have developed a blood biomarker algorithm that predicts the development of lethal GVHD seven days after HCT, which performed successfully in large multicenter validation sets. The GVH reaction is already in progress by day +7, even though clinical symptoms may not occur until days or weeks later. We speculate that the blood biomarker concentrations at this early time point reflect subclinical GI pathology, a notion that is reinforced by the fact that ST2 and REG3α, the two biomarkers in the algorithm, are closely associated with GI GVHD. The algorithm identified HR and LR strata in several patient groups with different overall risk for lethal GVHD (donor, HLA match, conditioning regimen intensity, age). This day +7 algorithm should prove useful in clinical BMT research by identifying patients at high risk for lethal GVHD who might benefit from aggressive preemptive treatment strategies. Disclosures Chen: Novartis: Research Funding; Incyte Corporation: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Jagasia:Therakos: Consultancy. Kitko:Therakos: Honoraria, Speakers Bureau. Kroeger:Novartis: Honoraria, Research Funding. Levine:Viracor: Patents & Royalties: GVHD biomarkers patent. Ferrara:Viracor: Patents & Royalties: GVHD biomarkers patent.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2016
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    In: Blood, American Society of Hematology, Vol. 128, No. 22 ( 2016-12-02), p. 510-510
    Abstract: Graft-versus-host disease (GVHD), the primary cause of non-relapse mortality (NRM) following allogeneic hematopoietic stem cell transplantation, does not always respond to treatment with high dose systemic corticosteroids. We have recently shown that a combination of three biomarkers (TNFR1, ST2, and REG3α) measured at onset of GVHD can predict day 28 response to treatment and 6-month NRM (Levine, Lancet Haem, 2015). Our goal in the current study was to determine if the same biomarker-based Ann Arbor GVHD algorithm can alsopredict treatment response andmortality whenapplied after one week of systemic corticosteroid treatment. The study population consisted of 378 patients (pts) with acute GVHD from 11 centers in the Mount Sinai Acute GVHD International Consortium. All pts were treated with systemic steroids and provided a plasma or serum sample obtained after one week of treatment (±3 days). The median starting dose of systemic steroids for Grade II-IV GVHD was 2.0 mg/kg/day and for Grade I was 1.0 mg/kg/day, after which treatment varied. Patients were divided into test (n=236) and validation (n=142) cohorts. We applied the Ann Arbor GVHD algorithm to concentrations of TNFR1, ST2, and REG3α measured after one week of treatment to generate a predicted probability of 6-month NRM, which we term the treatment score (TS). We employed unsupervised k-medoidclustering to partition TS values from the test cohort into two groups (high and low). This unbiased approach identified a high score group made up of 25% of pts (n=58) in the test cohort. We observed that the day 28 response rate (complete, CR + partial, PR) was significantly lower in pts with high scores compared to low scores in the test cohort (24% vs 65%, p 〈 0.0001) (Fig 1A). Analysis of the validation cohort using the same TS definitions showed similar differences in response rates (22% vs 61%, p 〈 0.0001) (Fig 1B). Further, nearly four times as many pts with high scores in both cohorts died within 6 months from non-relapse causes compared to pts with low scores (test: 57% vs 17%, p 〈 0.0001; validation: 57% vs 14%, p 〈 0.0001) (Fig 1C/D). As expected, the majority of non-relapse deaths in pts treated for GVHD were directly attributable to GVHD (test: 95%; validation: 89%). Relapse rates for high and low score pts were similar (data not shown), and thus pts with a high TS experienced significantly worse overall survival in both cohorts (test: 37% vs 72%, p 〈 0.0001; validation: 38% vs 79%, p 〈 0.0001) (Fig 1E/F). Approximately half of the pts in each cohort (test: 48%; validation: 44%) responded (CR+PR) to the first week of steroids and these ptshad significantly lower 6-month NRM than non-responders (NR) (test: 17% vs 36%, p=0.0002; validation: 13% vs 36%, p=0.0014). Yet the TS continued to stratify mortality risk independently of clinical response. In the test cohort, pts with a high score comprised 16% of all early responders and experienced more than twice the NRM of early responders with a low score (33% vs 13%, p=0.022) (Fig 2A). Conversely, test cohort pts who did not respond by day 7, but had a low score, fared much better than non-responders with a high score (NRM 21% vs 68%, p 〈 0.0001) (Fig 2B). Two thirds of early non-responders comprised this more favorable group. These highly significant results reproduced in the independent validation cohort in similar proportions (CR+PR: 45% vs 6%, p=0.0003; NR: 61% vs 22%, p=0.0001) (Fig 2C/D). Finally, a subset analysis revealed that pts classified as NR after one week of steroids due to isolated, yet persistent, grade I skin GVHD (24/378, 6%) overwhelmingly had low treatment scores (22/24, 92%) and experienced rates of NRM (9%) comparable to responders with low scores, thus forming a distinct, albeit small, subset of pts with non-responsive GVHD that fares particularly well (Fig 3). In conclusion, a treatment score based on three GVHD biomarkers measured after one week of steroids stratifies pts into two groups with distinct risks for treatment failure and 6-month NRM. It is particularly noteworthy that the TS identifies two subsets of pts with steroid refractory (SR) GVHD who have highly different outcomes (Fig 2B/D). The much larger group, approximately two thirds of all SR pts, may not need the same degree of treatment escalation as is traditional for clinical non-response, and thus overtreatment might be avoided. Because the TSis measured at a common decision making time point, it may prove useful to guide risk-adapted therapy. Disclosures Mielke: Novartis: Consultancy; MSD: Consultancy, Other: Travel grants; Celgene: Other: Travel grants, Speakers Bureau; Gilead: Other: Travel grants; JAZZ Pharma: Speakers Bureau. Kroeger:Novartis: Honoraria, Research Funding. Chen:Incyte Corporation: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding. Jagasia:Therakos: Consultancy. Kitko:Therakos: Honoraria, Speakers Bureau. Ferrara:Viracor: Patents & Royalties: GVHD biomarker patent. Levine:Viracor: Patents & Royalties: GVHD biomarker patent.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2016
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    In: Blood, American Society of Hematology, Vol. 128, No. 22 ( 2016-12-02), p. 2718-2718
    Abstract: Mutations of MIR142 have been identified in approximately 2% of de novo AML and in 20% of diffuse large B cell lymphoma (DLBCL). In AML, all of the mutations in MIR142 localize to the seed sequence of miRNA-142-3p, which is crucial in determining its target specificity. Previously, we showed that these mutations disrupt both miRNA-142-3p and miRNA-142-5p function, suggesting that loss of MIR142 plays a role in leukemic transformation (Yao et al, ASH abstract 1254, 2015). To test this hypothesis, we first characterized hematopoiesis in Mir142-/-mice. We previously reported that loss of Mir142 results in an expansion of myeloid progenitors with impaired erythropoiesis and lymphopoiesis (Yao, ASH abstract 1254, 2015). We now extend these analyses to investigate how loss of Mir142 promotes leukemic transformation. In the TCGA AML cohort, all 4 cases with somatic mutations in MIR142 also harbored mutations in either IDH1 or IDH2. To assess the functional importance of this association, we transduced wild-type or Mir142-/-hematopoietic stem/progenitor cells (HSPCs) with a retrovirus expressing the canonical IDH2 mutation, R172K. These cells were transplanted into lethally irradiated recipients and a tumor watch established. Loss of Mir142 alone was associated with mild splenomegaly, anemia, and leukopenia, but it was not sufficient to induce AML. Consistent with a prior report (Sasaki et al, Nature 2012), expression of IDH2 R172K alone induced a myeloproliferative disorder (MPD) characterized by increased myeloid cells, anemia, and splenomegaly. Concomitant loss of Mir142 did not affect the latency or penetrance of this MPD. However, the MPD in the double mutant mice was characterized by an increased percentage of CD34+ Gr1+ myeloblasts in the bone marrow and spleen plus a more severe anemia. To assess leukemia-initiating activity, we transplanted one million splenic cells into secondary recipients. Whereas IDH2 R172K alone cells rarely engrafted, Mir142-/- x IDH2 R172K cells efficiently engrafted and produced an MPD-like phenotype. These data suggest that loss of function mutations in MIR142 cooperate with IDH1/2 mutations to induce AML, possibly by increasing leukemic cell self-renewal. We examined several putative miR-142 target genes, eventually focusing on ASH1L. ASH1L is a member of the trithorax family of histone methyltransferases that has been recently implicated in MLL-associated leukemogenesis. The 3' UTR of ASH1L contains 4 putative binding sites for miRNA-142-3p, suggesting that this miRNA is critical in its post-transcriptional regulation. Indeed, in a luciferase assay with the ASH1L 3' UTR, MIR142 overexpression decreased translation by 80 percent. Consequently, Ash1l protein levels were 3 fold higher in Mir142-/- mice bone marrow compared to control mice. Since ASH1L is a key regulator of HOX gene expression, we examined HoxA9 and HoxA10 expression in Mir142-/- hematopoietic progenitor subsets. While HoxA9 and HoxA10 expression were not different in hematopoietic stem cells, they were markedly upregulated in myeloid progenitors. For example, in granulocyte-macrophage progenitors (GMPs), HoxA9 and HoxA10 expression were increased 2.86-fold and 34.4-fold, respectively in Mir142-/- versus control cells. Likewise, in megakaryocyte-erythroid progenitors (MEPs), HoxA9 and HoxA10 expression were increased 5.3-fold and 21.4-fold. Dysregulated HoxA9 and HoxA10 expression have been implicated in enhanced self-renewal capacity, and HoxA9 overexpression has been shown to cooperate with mutant IDH1 to induce AML in mice (Chaturvedi et al, Blood 2013). Collectively, these data suggest a model in which MIR142 mutations contribute to leukemogenesis by derepressing ASH1L expression, which, in turn, increases expression of HoxA9/10 and enhances self-renewal. Inhibitors targeting ASH1L may have therapeutic benefit in AML characterized by increased HOX gene expression. Disclosures No relevant conflicts of interest to declare.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2016
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 78, No. 13 ( 2018-07-01), p. 3510-3521
    Abstract: Point mutations in the seed sequence of miR-142-3p are present in a subset of acute myelogenous leukemia (AML) and in several subtypes of B-cell lymphoma. Here, we show that mutations associated with AML result both in loss of miR-142-3p function and in decreased miR-142-5p expression. Mir142 loss altered the hematopoietic differentiation of multipotent hematopoietic progenitors, enhancing their myeloid potential while suppressing their lymphoid potential. During hematopoietic maturation, loss of Mir142 increased ASH1L protein expression and consequently resulted in the aberrant maintenance of Hoxa gene expression in myeloid-committed hematopoietic progenitors. Mir142 loss also enhanced the disease-initiating activity of IDH2-mutant hematopoietic cells in mice. Together these data suggest a novel model in which miR-142, through repression of ASH1L activity, plays a key role in suppressing HOXA9/A10 expression during normal myeloid differentiation. AML-associated loss-of-function mutations of MIR142 disrupt this negative signaling pathway, resulting in sustained HOXA9/A10 expression in myeloid progenitors/myeloblasts and ultimately contributing to leukemic transformation. Significance: These findings provide mechanistic insights into the role of miRNAs in leukemogenesis and hematopoietic stem cell function. Cancer Res; 78(13); 3510–21. ©2018 AACR.
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2018
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    Online Resource
    Online Resource
    American Association for Cancer Research (AACR) ; 2017
    In:  Cancer Research Vol. 77, No. 13_Supplement ( 2017-07-01), p. 3042-3042
    In: Cancer Research, American Association for Cancer Research (AACR), Vol. 77, No. 13_Supplement ( 2017-07-01), p. 3042-3042
    Abstract: MIR142 mutations have been identified in acute myeloid leukemia (AML) and non-Hodgkins lymphoma. In AML, all MIR142 mutations localize to the miR-142-3p seed sequence. We show that mutated MIR142 is unable to suppress several well-known targets of miR-142-3p. Interestingly, the mutations of miR-142-3p result in their preferential loading into the RNA-induced silencing complex, leading to the degradation of miR-142-5p. Accordingly, miR-142-5p expression is decreased in MIR142 mutated AML. Hence, MIR142 mutations in AML disrupt both miR-142-3p/5p functions. Thus, we modeled the effect of MIR142 mutations on hematopoiesis using Mir142-/- mice. We show that loss of miR142 results in significant increases in myeloid hematopoietic stem/progenitor cells (HSPCs), including granulocyte-macrophage progenitors, myeloid-biased multipotent progenitors (CD150- CD48+ Flk2- Kit+ Sca+ lineage-) and CD229- myeloid-biased HSCs (CD150+ CD48- Kit+ Sca+ lineage-). In contrast, there are significant decreases of megakaryocyte-erythroid progenitors and erythroid precursors. Although the number of HSCs is normal in Mir142-/- mice, HSC transplantation suggest that they are myeloid-biased. In AML, MIR142 mutations are commonly found in conjunction with mutations of IDH1/2. To assess the importance of this association, we transduced wildtype or Mir142-/- HSPCs with retrovirus expressing IDH2 R172K and then transplanted into lethally irradiated recipients. Expression of IDH2 R172K alone was sufficient to induce a lethal myeloproliferative neoplasm (MPN). In contrast, Mir142-/- alone did not result in MPN. However, loss of Mir142 cooperates with IDH2 R172K to produce a more severe MPN, with increased CD34+ blasts and more severe anemia. Moreover, secondary transplantation shows that Mir142-/- x IDH2 R172K cells but not IDH2 R172K cells efficiently engraft and induce MPN, suggesting that loss of miR142 increases leukemia-initiating activity. We identify the histone methyltransferase ASH1L as a target gene of miR142 that contributes to altered hematopoiesis in Mir142-/- mice. The 3’-untranslated region of ASH1L has four miR-142-3p binding sites, and luciferase reporter assay shows that miR142 suppresses its translation by 80%. Consistent with this observation, Ashl1 protein expression is 3-fold higher in Mir142-/- bone marrow. ASH1L is a key positive regulator of HOX gene expression. Accordingly, we observed markedly (5-10 fold) increased HoxA9/A10 expression in myeloid progenitors in Mir142-/- mice. Likewise, HoxA9/A10 expression is increased in CD34+ blasts from Mir142-/- x IDH2 R172K transplanted mice. Of note, increased HoxA9 expression has been shown to cooperate with mutant IDH1 to induce AML in mice. Together, these findings support a model in which loss-of-function mutations of MIR142 contribute to hematopoietic malignancies by derepressing ASH1L and inducing HOXA9/10 gene expression. Citation Format: Juo-Chin Yao, Terrence N. Wong, Maria Trissal, Rahul Ramaswamy, Yaping Sun, Pavan R. Reddy, Daniel C. Link. MIR142 loss-of-function mutations promote leukemogenesis through derepression of ASH1L resulting in increased HOX gene expression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3042. doi:10.1158/1538-7445.AM2017-3042
    Type of Medium: Online Resource
    ISSN: 0008-5472 , 1538-7445
    RVK:
    RVK:
    Language: English
    Publisher: American Association for Cancer Research (AACR)
    Publication Date: 2017
    detail.hit.zdb_id: 2036785-5
    detail.hit.zdb_id: 1432-1
    detail.hit.zdb_id: 410466-3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    In: Blood, American Society of Hematology, Vol. 128, No. 22 ( 2016-12-02), p. 810-810
    Abstract: The two Inhibitors of apoptosis proteins (IAPs), X-chromosome-liked linked IAP (XIAP) and cellular IAP1 (cIAP1), inhibit apoptosis and are important in leukemogenesis. Recent data suggest that both xIAP and cIAP play critical, non-overlapping roles in regulating innate and adaptive responses to certain stimuli. But the role of IAPs in allo-immunity is not known. We utilized distinct but complementary approaches, namely genetic and small molecule approaches to determine the role of IAPs in allo-immunity. We first utilized AT-406, a small molecule IAP antagonist that is also known as second mitochondria-derived activator of caspase (SMAC) mimetic. This SMAC mimetic, is a pan-IAP inhibitor (inhibits both XIAP and cIAP) and reduces TNFα secretion in vitro. Because of the GVHD potentiating effects of TNFα, we hypothesized that treatment of allogeneic animals with AT-406 will reduce GVHD. We utilized B6→BALB/c MHC-mismatched BMT model. BALB/c recipients were lethally irradiated (8.5Gy) and transplanted withsyngeneic or allogeneic T cells along with bone marrow (BM). Both groups received either AT-406 or its diluent. Surprisingly, allo-recipients receiving AT-406 showed significantly worse GVHD severity and died more rapidly (p 〈 0.05). This observation was also noted in another MHC disparate haploidentical B6→F1 model. To further understand the role of IAPs, we next utilized genetic approach. When donor T cells from B6- cIAP-/- or XIAP-/- animals were compared to T cells from WT-B6, the allo-recipients (BALB/c) showed similar GVHD severity and mortality. Same results were also observed in a second B6→F1 model. Furthermore, in vitro studies showed that XIAP-/- and cIAP-/- T cells had comparable proliferation and cytokine secretion as WT-T cells. These data suggested that increase in GVHD mortality following treatment with AT-406 is not due to its effects on donor T cells. We therefore hypothesized that the absence of IAPs in hosts may impact on GVHD. To test this, cIAP-/-, XIAP-/- and WT-B6 animals were utilized as recipients in BALB/càB6 model. When compared with WT recipients both XIAP-/- and cIAP-/- recipients showed increased mortality (p 〈 0.001) and worse clinical and histopathological GVHD (p 〈 0.05, GI tract). We then determined whether IAPs expression on host hematopoietic derived cells is critical. We generated [B6→B6Ly5.2], [cIAP-/-→B6Ly5.2] and [XIAP-/-→B6Ly5.2] chimeras and utilized them as recipients in 2nd allo-BMT in BALB/càB6 models. All three chimeras, [B6→B6Ly5.2] [cIAP-/-→B6Ly5.2] and [XIAP-/-→B6Ly5.2] chimeras showed equivalent GVHD severity and mortality. Consistently, DCs from XIAP-/- and cIAP-/- animals showed similar functions as WT-B6 in vitro, suggesting that IAP expression in host hematopoietic-derived immune cells is not critical for GVHD. Next, to test the role of IAPs in non-hematopoietic GVHD target tissues, we made the reverse chimeras, namely, [B6Ly5.2→B6], [B6Ly5.2→XIAP-/-] and [B6Ly5.2→cIAP1-/-], where IAPs are absent only in the non-hematopoietic host cells. The allogeneic [B6Ly5.2→XIAP-/-] and [B6Ly5.2→cIAP1-/-] animals demonstrated a significantly worse survival compared to WT [B6Ly5.2→B6] recipient (p 〈 0.01). To determine the potential mechanisms for enhanced mortality, we tested the expression of anti-apoptotic genes (Bcl-2, Bcl-xl) and autophagy (LC3) in the CD326+ intestinal epithelial cells from KO and WT animals harvested after allo-BMT. The cIAP-/- and -XIAP-/- animals showed significantly reduced expression of Bcl-2, Bcl-xl and LC3 than allo-WT animals. These data suggest that enhanced apoptosis and reduced autophagy in the target tissues in the absence of cIAP and XIAP caused greater GVHD. Thus expression of functional IAPs in host target tissues is crucial for reducing the damage from GVHD. Figure 1 Pan-IAPs inhibitor (AT406) exacerbates GVHD. Figure 1. Pan-IAPs inhibitor (AT406) exacerbates GVHD. Figure 2 IAPson host target tissues protect GVHD. **p 〈 0.01, ***p 〈 0.001 Figure 2. IAPson host target tissues protect GVHD. **p 〈 0.01, ***p 〈 0.001 Disclosures No relevant conflicts of interest to declare.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2016
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    In: Blood, American Society of Hematology, Vol. 128, No. 22 ( 2016-12-02), p. 1157-1157
    Abstract: Gastrointestinal (GI) tract is bathed by metabolites derived from the resident microbiota. Recent data suggest that these microbiome metabolites affect the severity of various inflammatory conditions including graft versus host disease (GVHD). Specifically, microbiota-derived metabolites, short chain fatty acids (SCFAs) such as butyrate have been shown to ameliorate GVHD severity. But the key sensors and the mechanisms for mediating microbial metabolite dependent effects on intestinal epithelial cells (IECs), and GVHD remain unknown. We sought to determine the key microbial metabolite sensors for SCFA that control the severity of GVHD. We first analyzed for the expression of various G protein-coupled receptors (GPRs) and Solute Carrier Family 5 (SLC5) members that are expressed on IECs and known to be critical sensors of microbial metabolites, SCFAs. We utilized the well-characterized MHC disparate GVHD murine model BALB/c→B6. The recipient B6 mice were lethally irradiated (10Gy) and received 5x106 BM and 2.5x106 splenic T-cells from either syngeneic B6 or allogeneic BALB/c donors. The IECs were harvested at days +7 and +14 after BMT and analyzed for expression of GPR41, GPR43 and GPR101a, SLC5A members. The allogeneic animals demonstrated significantly reduced expression of GPR43 and SLC5A8. To determine the functional relevance of these receptors we next focused on GPR43. We obtained GPR43 deficient animals (GPR43KO) on B6 background and utilized them as allogeneic recipients in the same model as above. Compared with allogeneic wild type (WT) recipients, GPR43KO mice showed significantly more severe clinical severity (P 〈 0.05) and mortality from GVHD (P 〈 0.02). Histopathological analyses confirmed greater GI GVHD. IECs harvested from the WT and GPR43KO recipients demonstrated equivalent IFNγ, IL-17 and TNFα, similar levels in serum and equivalent expansion on day +14. GPR43 is also expressed on immune cells in addition to IECs. To dissect the cellular mechanisms we systematically explored the effect of GPR43 on myeloid derived DCs, T cells and IECs. The DCs from both WT and GPR43KO showed no significant differences in phenotype, functional responses to TLR stimulation with LPS and capacity to induce proliferation of allogeneic T cells. In vitro stimulation of T cells from the KO and WT animals showed comparable responses. Absence of GPR43 on donor cells did not enhance GVHD. Next we examined the effect of GPR43 on IECs. Recent data suggest that the levels of IEC protective cytokine IL-18 in response to activation of NLRP3 by microbial derived products is dependent on GPR43. We determined whether the levels of IL-18 expression in IECs and serum after allo-BMT in the KO and WT animals. IL-18 was significantly decreased in GPR43KO recipients compared to the WT animals (P 〈 0.05). Furthermore IEC explant cultures revealed GPR43KO IECs produce similar IL-18 upon direct stimulation of NLRP3. Next, butyrate, a critical microbiome derived metabolites that is a well-described ligand of GPR43 has been recently shown to mitigate GVHD by protecting IECs. Therefore to further explore the potential mechanisms for increase in GVHD in the GPR43 KO recipients we utilized the similar BALB/c→B6 model as above and tested the hypothesis that butyrate will not reduce GVHD in the GPR43KO recipients. We administered butyrate (10mg/kg) or the diluent daily by oral gavage from day 0 to day 21 to the GPR43KO and WT allogeneic recipients. Contrary to our hypothesis, we made surprising observation that butyrate treated allogeneic GPR43KO animals showed significantly reduced GVHD mortality (P 〈 0.05) than diluent treated GPR43KO animals. However, WT animals that received butyrate showed significantly better survival than the butyrate treated GPR43KO animals (P 〈 0.04). These data demonstrated that butyrate mediates GVHD protection in both GPR43 dependent and independent manner. Also suggest that the GPR43 independent protective effects of butyrate could be from its role as an energy source and histone deacetylase functions on IECs. Thus collectively our data suggest that GPR43 is a critical sensor of microbial metabolites such as butyrate and plays a key role in mitigating GVHD severity in an immune cell independent but in a potentially IEC dependent manner and thus provide mechanistic insights into the role of microbiome derived metabolites in reducing GVHD. Disclosures No relevant conflicts of interest to declare.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2016
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    Online Resource
    Online Resource
    IOP Publishing ; 2015
    In:  Nanotechnology Vol. 26, No. 19 ( 2015-05-15), p. 195502-
    In: Nanotechnology, IOP Publishing, Vol. 26, No. 19 ( 2015-05-15), p. 195502-
    Type of Medium: Online Resource
    ISSN: 0957-4484 , 1361-6528
    Language: Unknown
    Publisher: IOP Publishing
    Publication Date: 2015
    detail.hit.zdb_id: 1362365-5
    SSG: 11
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...