julilili42/papers huggingface dataset:
Dose-Escalation with BEACOPP Escalated Is Superior to ABVD In the Combined-Modality Treatment of Early Unfavorable Hodgkin Lymphoma: Final Analysis of the German Hodgkin Study Group (GHSG) HD14 Trial
2010-11-19

Abstract Abstract 765 Purpose: Combined modality treatment consisting of 4 cycles of chemotherapy and IF-RT is the standard treatment for early unfavorable HL. Overall survival (OS) and freedom from treatment failure (FFTF) at 5 years in this group of patients was 91% and 83%, respectively, in our prior HD8 study. Thus, the rationale for HD14 was to improve on these results by increasing dose intensity using BEACOPP escalated. Methods: Between January 2003 and July 2008, 1655 patients with histologically confirmed diagnosis of Hodgkin lymphoma in early unfavorable stages were randomized. Patients had to be 16–60 years old and have CS I, IIA with one of the following risk factors: large mediastinal mass (a), extranodal disease (b), elevated ESR (c), or ≥ 3 nodal areas (d), IIB with risk factors c or d). Patients were randomized to either 4 cycles of ABVD (arm A) or 2 cycles BEACOPP escalated followed by 2 cycles ABVD (arm B). All patients received 30Gy IF-RT after chemotherapy. Primary objective was the improvement of FFTF. Results: The full analysis set comprised 1623 patients (98.1%) who were documented and followed for treatment effects; 818 were in arm A and 805 in arm B. Patient characteristics were well balanced between the two arms with a median age of 33.6 years and most patients in stage IIA (67%). The overall response rate to treatment was 95% in each arm. With a median follow-up of 42.4 months, 20 patients had died in each arm; 19 patients in arm A had secondary neoplasia compared to 16 patients in arm B. Progressive disease was observed in 2.9% versus 0.9% of patients in arms A and B, respectively; early relapse rates were 2.8% versus 0.9%, and late relapse rates were 2.3% versus 0.9%. The estimated 4-year FFTF rate was 89.3% in arm A and 94.7% in arm B (p=0,0001, hazard ratio HR=2.04, 95%-CI: 1.39–2.94). There was no significant difference in overall survival yet (p=0.95). Acute grade III-IV toxicity rates of chemotherapy were higher in arm B (87.1%) than in arm A (50.7%) with leucopenia rates of 79% versus 24%, hair loss 48% versus 24%, thrombocytopenia 22% versus 0.1% and anemia 9% versus 1% in arms B and A respectively. 7.3% of patients had grade III/IV infections in arm B as compared to 3.4% in arm A. However, we observed no differences in treatment-related death or secondary neoplasia rates between treatment arms. Conclusion: Intensifying treatment for patients with early unfavorable HL using 2 cycles of BEACOPP escalated followed by 2 × ABVD and IFRT results in a significant improvement in tumor control as compared to our prior standard of 4 × ABVD plus IFRT. As defined in the study protocol, this more aggressive treatment was implemented as new standard of care for early unfavorable HL in our follow-up study (GHSG HD17). Disclosures: Greil: Cephalon: Research Funding.
Pseudoexpression of Glucocorticoid-Induced TNF-Related (GITR) Ligand Upon Coating of Cancer Cells by Platelets Impairs NK Cell Anti-Tumor Reactivity
2010-11-19

Abstract Abstract 3193 NK cells as part of the innate immune system substantially contribute to cancer immune surveillance. They prevent tumor progression and metastasis due to their ability to mediate cellular cytotoxicity and to produce cytokines like IFN-γ, which, among others, stimulates subsequent adaptive immune responses. NK reactivity results from an integrative response emerging upon recognition of multiple ligands for activating and inhibitory NK cell receptors including various members of the TNFR family. Apart from the direct interaction with their target cells, NK cell activity is further influenced by the reciprocal interplay with various other hematopoietic cells like e.g. dendritic cells. Metastatic tumor spread in experimental animals is dramatically reduced in thrombopenic mice. Additional depletion of NK cells reverses this effect, indicating that platelets may impair NK anti-tumor reactivity. However, the underlying mechanisms have not been fully elucidated, especially in humans. Recently, we demonstrated that NK anti-tumor immunity is impaired by platelet-derived TGF-β, which is released upon interaction of platelets with tumor cells (Kopp et al., Cancer Res. 2009). Here we report that the ligand for the TNFR family member GITR (GITRL) is upregulated on megakaryocytes during maturation resulting in substantial GITRL expression by platelets. Since we recently identified GITR as inhibitory NK receptor involved in tumor immune escape (e.g., Baltz et al., Blood 2008, Baessler et al., Cancer Res. 2009) we investigated how platelet-derived GITRL influences platelet function and NK immune surveillance. Signaling via GITRL into platelets upon interaction with NK-expressed GITR or recombinant GITR-Ig fusion protein did not alter platelet activation as revealed by analysis of the activation marker CD62P and release of TGF-β. Interestingly, we found that GITRL-negative tumor cells rapidly get coated by platelets, which confers a seemingly GITRL-positive phenotype. “GITRL pseudoexpression” on tumor cells caused a substantial reduction of NK cell cytotoxicity and cytokine production. This reduced NK reactivity was not due to induction of apoptosis via GITR and could be restored by addition of a blocking GITR antibody. Thus, coating of tumor cells by platelets inhibits NK reactivity, which is in part mediated by platelet-derived GITRL. Our data provide a functional basis for the previously observed finding that platelets increase metastasis i.e. by enabling evasion of tumor cells from NK-mediated immune surveillance. Disclosures: No relevant conflicts of interest to declare.
RANKL Expressed by Acute Myeloid Leukemia Cells Impairs NK Cell-Mediated Immune Surveillance
2010-11-19

Abstract Abstract 2164 NK cells play an important role in tumor immunosurveillance, especially of leukemia. Their reactivity is governed by various activating and inhibitory molecules expressed by their targets including multiple members of the TNF family. The TNF family member Receptor Activator of NF-κB ligand (RANKL) and its receptors RANK and osteoprotegerin (OPG) are key regulators of bone remodelling, but recently have also been shown to influence progression of hematopoetic malignancies. Here we studied the yet unkown role of the RANK/RANKL molecule system in NK cells and their reactivity against acute myeloid leukemia (AML). Primary leukemia cells from AML patients were found to substantially express RANKL mRNA and surface protein in 75% of the investigated cases (n=40). Reverse signaling via surface-expressed RANKL into AML blasts induced the release of soluble factors including the immunoregulatory cytokines TNF and IL-10, which impaired NK cell anti-tumor reactivity. Moreover, we observed upregulation of RANK on NK cells among PBMC of healthy donors upon exposure to IL-10. This was not caused by direct effects on NK cells, but was rather due to yet unidentified factors released by monocytes among the PBMC upon IL-10 exposure and could be prevented by the activating cytokine IL-2. Furthermore, functional experiments with NK cells and RANKL transfectants or RANKL-negative controls revealed that forward signaling into RANK-expressing NK cells by tumor-expressed RANKL also directly impaired NK cytotoxicity and IFN-γ production. In line, blocking RANK-RANKL interaction using anti-RANKL antibodies or RANK-Fc fusion protein increased cytotoxicity and cytokine production of allogenic NK cells in cultures with RANKL-positive primary AML cells. Our data indicate that RANKL expression enables immune evasion of leukemia cells both by directly inhibiting reactivity of RANK-expressing NK cells and by orchestrating a reciprocal interplay between AML cells, monocytes and NK cells resulting in an immunosuppressive cytokine milieu. Thus, therapeutic modulation of the RANK/RANKL system, e.g. with Denosumab/AMG162, which is presently being evaluated for treatment of both non-malignant and malignant osteolysis, holds promise to reinforce NK reactivity against hematopoietic malignancies. Disclosures: No relevant conflicts of interest to declare.
Adoptive Transfer of EBNA1-Specific T-Cells as a Treatment of Epstein-Barr-Virus Reactivation Following Allogeneic Stem Cell Transplantation
2010-11-19

Abstract Abstract 2342 Reactivation of Epstein-Barr-Virus (EBV) after allogeneic stem cell transplantation (SCT) is responsible for significant morbidity and mortality. EBV is also assotiated with the development of some malingancies, such as Burkitt-Lymphoma or nasopharyngeal carcinoma (NPC). In particular, the EBV-induced lymphoproliferative disorder (PTLD) is a rare but severe condition after SCT. PTLD is often associated with insufficient immune responses against EBV in transplant recipients. There is no effective antiviral drug treatment against EBV by now. Given that T-cell immunity is crucial for protection against infection or reactivation of EBV, cellular immunotherapy is a promising therapeutic option. The Epstein-Barr-Virus Nuclear Antigen 1 (EBNA-1) has been shown to contain immunodominant T-cell epitopes with T-cell responses in the majority of the healthy population. Here we report adoptive EBNA-1-specific T-cell transfer in seven pediatric and adult patients with chemorefractory EBV-reactivation after allogenic SCT. Four patients had PTLD and one had metastatic relapse of a NPC. EBNA-1-specific T-cells were isolated from the SCT-donor by using an IFNγ-capture technique. These small T-cell populations were immediately infused to the patient without in vitro expansion steps. The adoptive T-cell transfer contained both, CD4+ T-helper cells and CD8+ cytotoxic T-cells. The patients with a mean age of 20 years were treated with antigen specific T-cells from haploidentical, matched unrelated or matched sibling donor SCT between day 72 and 410 post SCT. The T-cell dose varied from 150–7750 T-cells/ kg. No acute toxicity was observed. In vivo T-cell responses before adoptive T-cell transfer were absent and were detectable in all of the patients within the first weeks after adoptive transfer, associated with a partial clinical and/or virological response to the adoptive T-cell transfer. In three of the patients a second specific T-cell administration was needed to achieve an improvement of the EBV-related condition. PTLD or EBV-infection was not a cause of death in any of the other six patients. In conclusion we could show that adoptive T-cell-immunotherapy is safe, feasible and a promising therapeutic option in patients with EBV- infection and/or PTLD, having the advantage of not being immunosuppressive compared to chemotherapy against PTLD. Infusion of small IFNγ producing EBNA-1-specific T-cell populations resulted in an in vivo expansion of specific T-cells. Emergence of in vivo T-cell responses was closely associated with a clearance or reduction of the viral load. Disclosures: No relevant conflicts of interest to declare.
Lymphocytes Are Dispensable In Neutrophil Homeostasis.
2010-11-19

Abstract Abstract 2613 Introduction: In contrast to red cell or platelet homeostasis, the feedback mechanisms involved in the control of peripheral neutrophil numbers are incompletely understood. Granulocyte-Colony Stimulating Factor (G-CSF) is generally accepted to be the most important determinant of neutrophil production and release from the bone marrow. Recently, a feedback loop including a specialized subset of T-lymphocytes (Tn cells) has been established to explain the correlation between peripheral neutrophil clearance and increased G-CSF production. Methods: Wild type C57bl/6 mice or NODSCIDcγ−/− received anti-Gr1 or anti-1A8 antibodies to deplete neutrophils. Hematopoietic tissues and peripheral blood were harvested at different times and analyzed on cellular, protein and RNA level. Results: Both anti-Gr1 and 1A8 antibodies reduced neutrophils effectively and persistently in vivo. The reaction on neutrophil depletion in the marrow uniformely consisted of an absolute increase in lin-/Sca1+/c-kit+ (LSK) cells and a shift of myeloid progenitors towards granulocyte-macrophage precursors (GMP) and common myeloid progenitors (CMP) at the expense of megakaryocyte-erythrocyte precursors (MEP). Of note, exogenous G-CSF resulted in identical changes. We therefore hypothesized that neutrophil depletion increases G-CSF through a feedback regulatory loop. Neutrophil depletion with anti-Gr1 antibody in wt mice increased G-CSF levels up to approximately 8-fold. While previous observations suggest that G-CSF may be passively regulated through receptor binding and internalization by mature neutrophils, we also found a 10-fold increase of G-CSF mRNA in the marrow. These findings are consistent with active feedback. Interestingly, the effects of 1A8 antibody on G-CSF were less pronounced. Instead, mice depleted of neutrophils with 1A8 antibody displayed predominant increases of M-CSF, suggesting redundant feedback pathways. Our results in wildtype mice treated with 1A8 antibody confirm previous data by Stark et al. (Immunity 2005; 22: 285–294), including increases of IL-23 and IL-17 after neutrophil depletion. However, when neutrophils were depleted in NODSCIDcγ−/− mice, who lack lymphocytes and NK-cells, both IL-23 and IL-17 remained unchanged, but G-CSF levels still increased markedly. Conclusions: Effective neutrophil depletion by antibodies directed against different neutrophil antigens uniformly results in major shifts in the hematopoietic bone marrow showing an increase in the number of LSK hematopoietic stem cells accompanied by a significant increase in myeloid progenitors at the expense of thrombopoietic, red cell, and lymphoid precursors. Our results demonstrate regulatory feedback loops of neutrophil granulopoiesis culminating in increased production of myelopoiesis stimulating cytokines such as G-CSF, GM-CSF, and M-CSF. The underlying chain of events includes IL-23 and IL-17 in wild type mice as previously described. However, additional redundant pathways exist in lymphocytopenic NODSCIDcγ−/− mice. Disclosures: No relevant conflicts of interest to declare.
Treosulfan, Etoposide and Cyclophosphamide as Non TBI-Conditioning Regimen Followed by Allogeneic SCT for Acute Lymphoblastic Leukemia
2010-11-19

Abstract Abstract 1327 Total body irradiation (TBI) is an essential part of the conditioning regimen for acute lymphablastic leukaemia (ALL) patients who undergo allogeneic stem cell transplantation. Due to high toxicity and mortality induced by TBI, we investigate in a multicenter prospective phase II study the toxicity and efficacy of a non TBI-based regimen consisting of treosulfan (3 × 12 g/m2), etoposide (30 mg/kg), and cyclophosphamide (120 mg/kg) in patients with ALL who underwent allogeneic stem cell transplantation. Major inclusion criteria were complete remission, indication for allogeneic stem cell transplantation according GMALL, non eligibility for TBI or patient's wish to avoid TBI. Graft-versus host prophylaxis consisted of cyclosporine A and short course methotrexat and in case of unrelated donors also of anti-lymphocyte globulin (ATG). This preliminary analysis is based on 36 patients (female: n=17; male: n=19) with a median age of 42 years (range: 18–60y). Remission-status at transplantation was either 1. CR (n=27), 2.CR (n=7) or &gt;2.CR (n=2). Donors were HLA-identical sibling (n=6), matched unrelated (n=21) or mismatched unrelated (n=9). 39% of the patients were Philadelphia chromosome positive. Primary graft failure was observed in 1 pts. The median time to achieve leukocyte (&gt; 1×109/l)) and platelet (&gt;20 × 109/l) engraftment was 22 (range, 11–47) and 24 days (range, 11–95), respectively. The toxicity was moderate including VOD (6%) and liver toxicity grade III (8%) and IV (3%). Acute graft versus host disease grade II-IV and grade III/IV was noted in 22% and 11%, respectively. Chronic graft versus host disease at 1 year was seen in 27%, which was extensive in 7% of the patients. After a median follow up of 12 months, the cumulative incidence of non-relapse mortality (NRM) at 1 year was only 9% (90% CI: 1–17%) and for relapse 37% (90% CI: 21–52%). The estimated 1-year disease free survival was 56% (90% CI:40-71%) and significantly better for patients transplanted in 1.CR vs 2. or higher CR (68% vs 15%, p=0.05). The estimated 1-year overall survival was 81% (90% CI: 69–92%). This preliminary results of a treosulfan, non TBI based conditioning regimen followed by allogeneic stem cell transplantation shows favourable toxicity profile with low non-relapse mortality. Longer follow up is needed to determine long-term freedom from disease. Disclosures: Kröger: MEDAC: Research Funding. Off Label Use: Treosulfan is not approved as conditioning regimen for stem cell transplantation.
Randomized Trial on GvHD Prophylaxis with or without Anti-T-Cell Globulin ATG-Fresenius (ATG-F) In Allogeneic Hematopoietic Cell Transplantation From Matched Unrelated Donors: Final Results and Analysis of Prognostic Factors
2010-11-19

Abstract Abstract 1249 Previously, we could demonstrate that addition of ATG-F to standard cyclosporine, methotrexate GvHD prophylaxis (control group) significantly reduces severe acute and chronic GvHD, without negatively affecting non-relapse mortality (NRM), relapse rate (RR), disease-free survival (DFS) or overall survival (OS) (Finke et al., Lancet Oncol, 2009). Here we present final data of extended follow-up with a median of 3 (25%-quartile 2.5, 75%-quartile 3.9) years on 201 patients with median age of 40 (range 18–60) years, transplanted between 2003 and 2007, with AML (n=101), MDS (n=10), ALL (n=70), CML (n=17), OMF (n=3) in early (1st CR or MDS-RA, n=107), or advanced status of disease (all other, n=94). At Day +100, the primary efficacy endpoint - severe acute GvHD (aGvHD grade III-IV) or death was reached in 21.4% of patients in the ATG-F group versus 34.7% in the control group (p=0.098). Incidence of grade III-IV aGvHD was 11.7% in the ATG-F group and 25.5% in the control group (p=0.039). With extended follow-up the incidence of extensive chronic GvHD (cGvHD) after three years was 12.2% in the ATG-F group versus 45.0% in the control group (p&lt;0.0001). DFS after three years was 48.0% in the ATG-F and 38.4% in the control group (p=0.71). Incidence of relapse after three years was 32.6% in the ATG-F and 28.2% in the control group (p=0.47). Incidence of NRM after three years was 19.4% in the ATG-F and 33.5% in the control group (p=0.18). OS after three years was 55.2% in the ATG-F and 43.3% in the control group (p=0.39). The effects of the prognostic factors patient age, donor age, patient/donor sex mismatch, patient/donor CMV status, HLA-C difference, type and status of disease, conditioning regimen, source of stem cells, cyclosporine trough levels during the first 30 days, on occurrence of aGvHD III-IV, extensive cGvHD, DFS, relapse, NRM, and OS were analyzed. Factors showing an effect with p&lt;0.05 in univariate analyses were analyzed in multivariate analyses (both adjusted for treatment). Donor age above 40 years negatively affected the risk for aGvHD III-IV (hazard ratio (HR)=2.6, p=0.009), extensive cGvHD (HR=2.1, p=0.021) and OS (HR=1.7, p=0.016); patient age above 40 years negatively influenced NRM (HR=1.8. p=0.041), whereas advanced disease was a risk factor for aGvHD III-IV (HR=2.1, p=0.018), DFS (HR 1.7, p=0.004), relapse (HR=1.7, p=0.038), and OS (HR=1.9, p=0.002). Conclusion: ATG-F significantly reduces severe acute and chronic GvHD. Younger donors are to be preferred in unrelated donor transplantation. Older and advanced disease patients need special precautions to improve outcome. Disclosures: Finke: Fresenius Biothech GmbH: Research Funding. Bethge:Fresenius Biothech GmbH: Lecture remuneration.
Transfer of MHC Class I by Coating Platelets Enables Tumor Cells to Evade NK Cell Immune Surveillance by Conferring a “Pseudo Self” Phenotype
2010-11-19

Abstract Abstract 583 NK cells are a central component of the cytotoxic lymphocyte compartment capable of lysing tumor cells without prior immune sensitization of the host. The mechanisms leading to activation of NK reactivity are described by the principles of ‘missing-self' and ‘induced-self', which imply that cells with a low or absent expression of MHC class I (‘missing-self') and/or a stress-induced expression of ligands of activating NK receptors like e.g. NKG2D (‘induced-self') are preferentially recognized and eliminated by NK cells. Thus, a balance of various activating and inhibitory signals determines whether NK cell responses are initiated or not. Tumor cells often downregulate expression of MHC class I to evade T cell-mediated immune surveillance, which results in enhanced NK susceptibility. Besides the direct interaction with their target cells, NK activity is further influenced by the reciprocal interplay with various other hematopoietic cells. We and others demonstrated previously that thrombocytopenia inhibits metastasis in murine models, which is reversed by additional depletion of NK cells (e.g., Jin et al., Nature Med. 2006, Palumbo et al., Blood 2005). However, the mechanisms by which platelets impair NK-tumor interaction are largely unclear, especially in humans. Recently we reported that platelets release TGF-β upon interaction with tumor cells causing downregulation of NKG2D on NK cells, which impairs anti-tumor immunity by disturbing the principle of “induced self” (Kopp et al., Cancer Res. 2009). Here we demonstrate that platelets further enable tumor cells to evade NK cell immune surveillance by preventing detection of “missing self”: We found that tumor cells rapidly get coated in the presence of platelets, the latter expressing large amounts of MHC class I on their surface. In case of MHC class I-negative or -low cancer cells, this process results in MHC class I “pseudoexpression” on the tumor cell surface as revealed by flow cytometry, immunofluorescent staining, and electron microscopy. Platelet-derived MHC class I was found to inhibit the reactivity of autologous NK, both upon activation with cytokines and, most importantly, in cultures with platelet-coated tumor cells. Using constitutively MHC class I-negative/low tumor cells we found that blocking MHC class I restored NK cytotoxicity and IFN-γ production against platelet-coated tumor cells, but did not alter NK reactivity against the tumor cells in the absence of coating platelets. Taken together, our data indicate that platelets enable a molecular mimicry of tumor cells, allowing the latter to downregulate MHC class I in order to escape T cell immunity without inducing sufficient NK tumor immune surveillance due to conferred platelet-mediated “pseudo self”. Disclosures: No relevant conflicts of interest to declare.