High-dose chemotherapy followed by autologous stem cell transplantation is a major component in the treatment of patients with multiple myeloma. As a prerequisite, the successful collection of a sufficient number of viable peripheral blood hematopoietic CD34+ cells is critical. A common standard protocol for mobilization is currently not defined and critically discussed especially in German-speaking Europe. In times of the Covid-19 pandemic, safe and effective strategies have to be chosen to minimize hospitalization times and severe courses. In this single-center retrospective analysis, safety and efficacy of cyclophosphamide plus etoposide (CE) and growth-factor support (n = 33) was compared to cyclophosphamide mono treatment and growth-factor support (n = 49) in 82 patients with multiple myeloma at first diagnosis. CE was superior to cyclophosphamide mono with a significantly higher number of collected CD34+ cells (15.46 × 106 CD34+ cells/kg vs. 9.92 × 106 CD34+ cells/kg), significantly faster engraftment of granulocytes after stem cell transplantation (day 10.5 vs. day 11.6), shorter duration of the inpatient stay (17.47 days vs. 19.16 days) and significantly less transfusions (8.82 % vs. 30.61 % patients receiving transfusions). The safety profile was comparable in both groups and in line with published data. We conclude that CE is a safe and highly effective mobilization protocol in patients with multiple myeloma at first diagnosis and appears to be superior to the commonly used cyclophosphamide mono regimen.

Recurrence of cytomegalovirus reactivation remains a major cause of morbidity and mortality following allogeneic hematopoietic stem cell transplantation. Monitoring cytomegalovirus-specific cellular immunity using a standardized assay might improve the risk stratification of patients. A prospective multicenter study was conducted in 175 intermediate- and high-risk allogeneic hematopoietic stem cell transplant recipients under preemptive antiviral therapy. Cytomegalovirus-specific cellular immunity was measured using a standardized IFN-γ ELISpot assay (T-Track® CMV). Primary aim was to evaluate the suitability of measuring cytomegalovirus-specific immunity after end of treatment for a first cytomegalovirus reactivation to predict recurrent reactivation. 40/101 (39.6%) patients with a first cytomegalovirus reactivation experienced recurrent reactivations, mainly in the high-risk group (cytomegalovirus-seronegative donor/cytomegalovirus-seropositive recipient). The positive predictive value of T-Track® CMV (patients with a negative test after the first reactivation experienced at least one recurrent reactivation) was 84.2% in high-risk patients. Kaplan-Meier analysis revealed a higher probability of recurrent cytomegalovirus reactivation in high-risk patients with a negative test after the first reactivation (hazard ratio 2.73; p=0.007). Interestingly, a post-hoc analysis considering T-Track® CMV measurements at day 100 post-transplantation, a time point highly relevant for outpatient care, showed a positive predictive value of 90.0% in high-risk patients. Our results indicate that standardized cytomegalovirus-specific cellular immunity monitoring may allow improved risk stratification and management of recurrent cytomegalovirus reactivation after hematopoietic stem cell transplantation. This study was registered at www.clinicaltrials.gov as #NCT02156479.

Background Further improvement of preparative regimens before allogeneic haemopoietic stem cell transplantation (HSCT) is an unmet medical need for the growing number of older or comorbid patients with acute myeloid leukaemia or myelodysplastic syndrome. We aimed to evaluate the efficacy and safety of conditioning with treosulfan plus fludarabine compared with reduced-intensity busulfan plus fludarabine in this population. Methods We did an open-label, randomised, non-inferiority, phase 3 trial in 31 transplantation centres in France, Germany, Hungary, Italy, and Poland. Eligible patients were 18-70 years, had acute myeloid leukaemia in first or consecutive complete haematological remission (blast counts <5% in bone marrow) or myelodysplastic syndrome (blast counts <20% in bone marrow), Karnofsky index of 60% or higher, and were indicated for allogeneic HSCT but considered at an increased risk for standard myeloablative preparative regimens based on age (>= 50 years), an HSCT-specific comorbidity index of more than 2, or both. Patients were randomly assigned (1:1) to receive either intravenous 10 g/m(2) treosulfan daily applied as a 2-h infusion for 3 days (days -4 to -2) or 0.8 mg/kg busulfan applied as a 2-h infusion at 6-h intervals on days -4 and -3. Both groups received 30 mg/m(2) intravenous fludarabine daily for 5 days (days -6 to -2). The primary outcome was event-free survival 2 years after HSCT. The non-inferiority margin was a hazard ratio (HR) of 1.3. Efficacy was assessed in all patients who received treatment and completed transplantation, and safety in all patients who received treatment. The study is registered with EudraCT (2008-002356-18) and ClinicalTrials.gov (NCT00822393). Findings Between June 13, 2013, and May 3, 2016,476 patients were enrolled (240 in the busulfan group received treatment and transplantation, and in the treosulfan group 221 received treatment and 220 transplanation). At the second preplanned interim analysis (Nov 9, 2016), the primary endpoint was met and trial was stopped. Here we present the final confirmatory analysis (data cutoff May 31, 2017). Median follow-up was 15.4 months (IQR 8.8-23-6) for patients treated with treosulfan and 17.4 months (6.3-23.4) for those treated with busulfan. 2-year event-free survival was 64.0% (95% CI 56.0-70.9) in the treosulfan group and 50.4% (42.8-57.5) in the busulfan group (HR 0.65 [95% CI 0.47-0.90]; p<0 =0001 for non-inferiority, p=0.0051 for superiority). The most frequently reported grade 3 or higher adverse events were abnormal blood chemistry results (33 [15%] of 221 patients in the treosulfan group vs 35 115%1 of 240 patients in the busulfan group) and gastrointestinal disorders (24 [11%] patients vs 39[16%] patients). Serious adverse events were reported for 18 (8%) patients in the treosulfan group and 17 (7%) patients in the busulfan group. Causes of deaths were generally transplantation-related. Interpretation Treosulfan was non-inferior to busulfan when used in combination with fludarabine as a conditioning regimen for allogeneic HSCT for older or comorbid patients with acute myeloid leukaemia or myelodysplastic syndrome. The improved outcomes in patients treated with the treosulfan-fludarabine regimen suggest its potential to become a standard preparative regimen in this population. Copyright (C) 2019 Elsevier Ltd. All rights reserved.

Increasing evidence suggests that impaired cytomegalovirus (CMV)-specific cell-mediated immunity (CMV-CMI) is a major cause of uncontrolled CMV reactivations and associated complications in hematopoietic stem cell transplantation (HSCT). No reliable test exists to predict patients at risk of primary and/or recurrent CMV reactivations following HSCT. Accurately assessing CMV-CMI might therefore improve the risk stratification of patients and allow optimizing and individualizing patient care.This study aimed to evaluate the suitability of a novel IFN-γ ELISpot assay (T-Track® CMV), based on the stimulation of peripheral blood mononuclear cells with T-activated® pp65 and IE-1 CMV proteins, to predict protection from recurrent CMV reactivation following the resolution of a treatment-requiring primary CMV reactivation.A prospective, longitudinal, observational, multicenter study was conducted in 175 intermediate- and high-risk (Donor (D)+/Recipient (R)+, D+/R-, D-/R+) HSCT recipients (ClinicalTrials.gov ID: NCT02156479). Patients underwent preemptive antiviral therapy per institutional guidelines. CMV DNAemia was analyzed by quantitative PCR. CMV-CMI was measured at day 45, 60, 80, 100 and 120 post-transplantation, as well as at onset and following the end of preemptive treatment. Occurrence of recurrent CMV reactivation was monitored up to 7.5 months post-transplantation. 154/175 patients fulfilling the inclusion/exclusion criteria and having at least one valid T-Track® CMV test result were included in the final analysis.101/154 (66%) patients experienced at least one (treatment-requiring) CMV reactivation during the observational period. Out of 74 patients (24 D+/R+, 3 D+/R-, 47 D-/R+) who experienced a first CMV reactivation and had a valid ELISpot test result at the end of this primary reactivation, 30 (41%) faced a recurrent CMV reactivation during the observational period. Interestingly, 41/44 patients free of recurrent reactivation had a positive test result (i.e. positive for at least one of pp65- and/or IE-1-specific result) after resolution of the primary CMV reactivation, resulting in a 93% specificity in diagnostic accuracy. Accordingly, a time-to-event analysis indicated a significantly lower incidence of recurrent CMV reactivation in patients with a positive test result (Figure 1; Hazard ratio=5.68; Log-Rank Test, p<0.001). A ROC analysis also demonstrated that pp65-specific response measured following a primary CMV reactivation is a good negative predictor for future CMV reactivation (AUC=0.840 [95% CI 0.741-0.939]; p<0.001).Altogether, this novel standardized IFN-γ ELISpot assay allows an improved risk stratification of CMV-related clinical complications, and can support clinicians in the identification and management of patients with increased risk of recurrent CMV reactivation following HSCT. Increasing evidence suggests that impaired cytomegalovirus (CMV)-specific cell-mediated immunity (CMV-CMI) is a major cause of uncontrolled CMV reactivations and associated complications in hematopoietic stem cell transplantation (HSCT). No reliable test exists to predict patients at risk of primary and/or recurrent CMV reactivations following HSCT. Accurately assessing CMV-CMI might therefore improve the risk stratification of patients and allow optimizing and individualizing patient care. This study aimed to evaluate the suitability of a novel IFN-γ ELISpot assay (T-Track® CMV), based on the stimulation of peripheral blood mononuclear cells with T-activated® pp65 and IE-1 CMV proteins, to predict protection from recurrent CMV reactivation following the resolution of a treatment-requiring primary CMV reactivation. A prospective, longitudinal, observational, multicenter study was conducted in 175 intermediate- and high-risk (Donor (D)+/Recipient (R)+, D+/R-, D-/R+) HSCT recipients (ClinicalTrials.gov ID: NCT02156479). Patients underwent preemptive antiviral therapy per institutional guidelines. CMV DNAemia was analyzed by quantitative PCR. CMV-CMI was measured at day 45, 60, 80, 100 and 120 post-transplantation, as well as at onset and following the end of preemptive treatment. Occurrence of recurrent CMV reactivation was monitored up to 7.5 months post-transplantation. 154/175 patients fulfilling the inclusion/exclusion criteria and having at least one valid T-Track® CMV test result were included in the final analysis. 101/154 (66%) patients experienced at least one (treatment-requiring) CMV reactivation during the observational period. Out of 74 patients (24 D+/R+, 3 D+/R-, 47 D-/R+) who experienced a first CMV reactivation and had a valid ELISpot test result at the end of this primary reactivation, 30 (41%) faced a recurrent CMV reactivation during the observational period. Interestingly, 41/44 patients free of recurrent reactivation had a positive test result (i.e. positive for at least one of pp65- and/or IE-1-specific result) after resolution of the primary CMV reactivation, resulting in a 93% specificity in diagnostic accuracy. Accordingly, a time-to-event analysis indicated a significantly lower incidence of recurrent CMV reactivation in patients with a positive test result (Figure 1; Hazard ratio=5.68; Log-Rank Test, p<0.001). A ROC analysis also demonstrated that pp65-specific response measured following a primary CMV reactivation is a good negative predictor for future CMV reactivation (AUC=0.840 [95% CI 0.741-0.939]; p<0.001). Altogether, this novel standardized IFN-γ ELISpot assay allows an improved risk stratification of CMV-related clinical complications, and can support clinicians in the identification and management of patients with increased risk of recurrent CMV reactivation following HSCT. Figure 1.

Impaired cytomegalovirus (CMV)-specific cell-mediated immunity (CMV-CMI) is a major cause of uncontrolled CMV reactivation and associated complications in both solid-organ transplantation (SOT) and hematopoietic stem cell transplantation (HSCT). Reliably assessing CMV-CMI is desirable to individually adjust antiviral and immunosuppressive therapy. We demonstrate here the suitability of a novel IFN-γ ELISpot assay (T-Track® CMV), based on the stimulation of PBMC with pp65 and IE-1 CMV proteins, to monitor CMV-CMI in SOT and HSCT patients. Two independent prospective, longitudinal, observational, multicenter studies were conducted: in 86 intermediate-risk (D−/R+, D+/R+) renal transplant recipients (completed), and in 175 intermediate- or high-risk (D+/R+, D+/R−, D−/R+) HSCT recipients (ongoing). In both studies, patients underwent pre-emptive antiviral therapy. CMV-CMI, CMV load and clinical complications were monitored over ~6 months post-transplantation. In the kidney transplantation setting, 95% and 88–92% of IFN-γ ELISpot test results were positive pre- and post-transplantation, respectively. CMV-specific response was reduced following immunosuppressive therapy and increased in patients with graft rejection, indicating the ability of the assay to monitor the patients’ immunosuppressive state. Interestingly, median pp65-specific response was 9-fold higher in patients with self-clearing viral load compared with antivirally-treated patients prior to first detection of CMV (MWU; P < 0.001), suggesting that reactivity to pp65 is a potential immunocompetence marker. In HSCT patients, interim data analysis indicates that pp65-specific CMI measured after resolution of a primary CMV reactivation (requiring antiviral treatment) is a fair predictor of occurrence of recurrent CMV reactivation. Out of 71 patients (25 D+/R+, 3 D+/R−, 43 D−/R+) who experienced a primary CMV reactivation, 27 encountered a recurrent CMV reactivation. Interestingly, 39/44 (89%) patients free of recurrent reactivation had a positive pp65-specific test result following primary CMV reactivation. Altogether, this novel IFN-γ ELISpot assay is a highly sensitive immune-monitoring tool with a potential use for the risk assessment of CMV-related clinical complications after SOT and HSCT. All authors, Lophius Biosciences: Investigator, Research support.

Abstract Abstract 2911 The bone disease in myeloma is the result of the complex interactions between myeloma cells and the bone marrow osteoclasts plus other accessory cells and microenvironmental components. The receptor activator of NfkappaB (RANK) and osteoprotegerin (OPG) cascade system have been reported to be an essential pathway in the osteoclastogenesis. Genetic variations in the genes coding for RANK, RANK ligand (RANKL), and OPG are supposed to play a role in the susceptibility of myeloma. In the present case control study genomic DNA was obtained in 217 myeloma patients including smoldering myeloma (age: mean 62, 33–88) and 516 healthy controls (healthy blood donors, HC; age mean: 44, 18–65). We studied six single-nucleotide-polymorphisms (SNPs) in the genes of RANK (2 SNPs, rs1805034, rs35211496), OPG (2 SNPs, rs3102735, rs2073618), and of RANKL (2 SNPs, rs9533156, rs2277438) using TaqMan assay guided polymerase chain reaction for the respective SNPs. The genotype and allelic frequencies comparing myeloma patients with HC were analyzed with χ2 test for 2×3 and 2×2 tables, respectively. The genotype distributions of the SNP rs2277438 in the RANKL gene and SNP rs3102735 in the OPG gene differed highly significantly (p=0.0001 and p=0.005, respectively) between myeloma patients and HC (table 1). No significantly increased risk was detected in the other SNP analyzed in the study. A subgroup analysis of the myeloma patients stratified into beta2 microglobulin levels lower or higher than 3.5 mg/l showed lower values to be significantly associated with the minor allele of the SNP rs3102735 in the OPG gene (major vs. minor allele in myeloma vs. HC: 77/23% vs. 89/11%; OR 2.49; CI 1.38–4.49). Further stratification into gender, serum calcium levels, hemoglobin values at diagnosis showed no differences.Table 1Myeloma patientsHealthy controls (HC)OR (CI)pRANKL rs2277438Allelen = 434 (%)n = 1024 (%)1324 (75)860 (84)1.7790.00012110 (25)164 (16)(1.373–2.341)Genotypen = 217 (%)n = 512 (%)11132 (61)360 (70)0.00011260 (28)140 (27)2225 (12)12 (2)OPG rs 3102735Allelen = 420 (%)n = 1028 (%)167 (16)109 (11)1.6000.0052353 (84)919 (89)(1.153–2.222)Genotypen = 210 (%)n = 514 (%)119 (4)5 (1)0.0051249 (23)99 (19)22152 (72)410 (80)RANK = receptor activator of NfkappaB, RANKL = receptor activator of NfkappaB ligand, OPG = osteoprotegerin, OR = odds ratio, CI = confidence intervals 95% To the best of our knowledge, this is the first study reporting a highly significant association of the SNP rs2277438 of the RANKL gene and the SNP rs3102735 in the OPG gene, respectively, with the susceptibility to develop myeloma in the Caucasian population. Both SNPs are associated with an increased risk for myeloma. However, myeloma patients carrying the minor allele of OPG SNP rs3102735 developed lower levels of the proliferation marker beta2 microglobulin. The impact of the OPG SNP rs3102735 (location: promoter region, chromosome 8q24) or of the SNP rs2277438 located in intron 1 (chromosome 13q14.11), a potentially regulatory region of the RANKL gene, on the regulation of RANKL expression is unclear. Disclosures: No relevant conflicts of interest to declare.

Background The MInT study was the first to show improved 3-year outcomes with the addition of rituximab to a CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone)-like regimen in young patients with good-prognosis diffuse large-B-cell lymphoma. Extended follow-up was needed to establish long-term effects.Methods In the randomised open-label MInT study, patients from 18 countries (aged 18-60 years with none or one risk factor according to the age-adjusted International Prognostic Index [IPI], stage II-IV disease or stage I disease with bulk) were randomly assigned to receive six cycles of a CHOP-like chemotherapy with or without rituximab. Bulky and extranodal sites received additional radiotherapy. Randomisation was done centrally with a computer-based tool and was stratified by centre, bulky disease, age-adjusted IPI, and chemotherapy regimen by use of a modified minimisation algorithm that incorporated a stochastic component. Patients and investigators were not masked to treatment allocation. The primary endpoint was event-free survival. Analyses were by intention to treat. This observational study is a follow-up of the MInT trial, which was stopped in 2003, and is registered at ClinicalTrials.gov, number NCT00400907.Findings The intention-to-treat population included 410 patients assigned to chemotherapy alone and 413 assigned to chemotherapy plus rituximab. After a median follow-up of 72 months (range 0.03-119), 6-year event-free survival was 55.8% (95% CI 50.4-60.9; 166 events) for patients assigned to chemotherapy alone and 74.3% (69.3-78.6; 98 events) for those assigned to chemotherapy plus rituximab (difference between groups 18.5%, 11.5-25.4, log-rank p<0.0001). Multivariable analyses showed that event-free survival was affected by treatment group, presence of bulky disease, and age-adjusted IPI and that overall survival was affected by treatment group and presence of bulky disease only. After chemotherapy and rituximab, a favourable subgroup (IPI=0, no bulk) could be defined from a less favourable subgroup (IPI=1 or bulk, or both; event-free survival 84.3% [ 95% CI 74.2-90.7] vs 71.0% [65.1-76.1], log-rank p=0.005). 18 (4.4%, 95% CI 2.6-6.9) second malignancies occurred in the chemotherapy-alone group and 16 (3.9%, 2.2-6.2) in the chemotherapy and rituximab group (Fisher's exact p=0.730).Interpretation Rituximab added to six cycles of CHOP-like chemotherapy improved long-term outcomes for young patients with good-prognosis diffuse large-B-cell lymphoma. The definition of two prognostic subgroups allows a more refined therapeutic approach to these patients than does assessment by IPI alone.Funding Hoffmann-La Roche.

Paratarg-7 (P-7) is a frequent paraprotein target in monoclonal gammopathy of undetermined significance (MGUS), multiple myeloma (MM), and Waldenström macroglobulinemia. Patients with P-7-specific paraproteins carry a hyperphosphorylated paratarg-7 (pP-7). Because pP-7 carrier state is dominantly inherited, we determined the paraprotein targets in 4 families with familial MGUS/MM. No antigenic target was identified for the paraproteins from 2 members of one family. Paraproteins from affected members of 2 other families targeted P-7, and paraproteins from 4 affected members of a fourth family targeted P-8, which is encoded by the ATG13 gene. P-8 was hyperphosphorylated in the affected family members (pP-8) and pP-8 carrier state is inherited in a dominant fashion. Six additional autoantigenic nonfamilial paraprotein targets were also hyperphosphorylated in the respective patients compared with normal controls. We conclude that paraproteins of affected members with familial MGUS/MM share family-typical hyperphosphorylated antigens and hyperphosphorylation of paraprotein targets might be a general mechanism underlying the pathogenesis of MGUS/MM.

Abstract Abstract 472 Hyperphosphorylated paratarg-7 (pP-7) is the target of paraproteins in 15% of Caucasian, 4.5% of Asian and 28% of Afro-American patients with MGUS/MM. Carriers of pP-7 have an 8 to 13 times increased risk to develop IgA/IgG-MGUS and multiple myeloma (Grass et al., Lancet Oncology 2009; 10:950–956) and a 6.5 times increased risk to develop IgM-MGUS and Waldenstrom`s macroglobulinemia (Grass et al., Blood. 2011 Mar 10;117(10):2918–23.). Analysis of affected families showed that pP-7 is inherited in a dominant fashion, explaining cases of familial MGUS/MM/WM. Since paratarg-7 is hyperphosphorylated and inherited in a dominant fashion, we extended our studies to investigate the prevalence of further antigenic targets of paraproteins and their phosphorylation state. All (8/8) autoantigenic paraprotein target (paratargs no. 2, 5, 6, 7, 8, 9, 10, and 11) moleculary defined to date were shown to be hyperphosphorylated in the respective patients compared to normal controls, and the hyperphosphorylation state of the respective paraproteins targets was shown to be inherited in a dominant fashion for all autoantigenic paraprotein targets for which enough family members were available for such an analysis. The consistent finding of hyperphosphorylation of autoantigenic paraprotein targets suggests a common underlying mechanism associated with the pathogenesis of MGUS/MM, and implies a significant role of the hyperphosphorylation state in the pathogenesis of these neoplasms. Co-immunoprecipitation identified PKCzeta as the kinase responsible for the phosphorylation of most and PP2A as the phosphatase responsible for the dephosphorylation of all hyperphosphorylated autoantigenic targets of paraproteins. SNPs or mutations of PKCzeta and PP2A as the reason for the abnormal phosphorylation of the paraproteins targets were excluded. However, PP2A was shown to be inactivated by phosphorylation of its catalytic subunit at Y307. To determine the SNP or mutation which is associated with the inactivation of PP2A we carried out a genome-wide linkage analysis. We found strong evidence for a parametric linkage (full penetrant autosomal dominant model; disease marker allele frequency=0.02) with a LOD score of 5.9 on chromosome 4q35. For pP-7 hyperphosphorylation we demonstrated that the hyperphosphrylation is due to an single additional phosphorylation at serine 17, which is located in the paraprotein-binding epitope of pP-7. Analysis of the T-cell response against normo- and hyperphosphorylated paratarg-7 derived peptides in affected and non-affected family members demonstrated that pP-7, but not wild-type p-7 induces a strong and specific CD4+ T-cell response in the patients with pP-7, which was shown to be HLA-DQ and HLA-DR restricted. This suggests that pP-7 confers a chronic antigenic stimulation which is mediated by CD4+ T-cells and that these pP-7 specific CD4+ T-cells stimulate a B-cell clone with the same specificity, eventually resulting in the clonal evolution of this B-cell clone. In summary, our results support the hypothesis of a role of chronic autoantigenic stimulation in the pathogenesis of MGUS/MM/WM. Indviduals carrying pP-7 are at particular risk, if their MHC-II haplotype allows the recognition of pP-7 derived antigenic peptides by their CD4+ T cells. We suggest that the different prevalence of pP-7 carriers and defined MHC-II haplotypes explain the different incidence rates of MGUS/MM/WM in different ethnic groups. Disclosures: Preuss: Ludwig Institute for Cancer Research: Patents & Royalties. Pfreundschuh:Ludwig Institute for Cancer Research: Patents & Royalties.

Hyperphosphorylated paratarg‐7 (pP‐7) is a frequent target of paraproteins in German patients with monoclonal gammopathy of undetermined significance (MGUS)/multiple myeloma (MM). The frequency of MGUS/MM is lower in Japan than in Europe. As pP‐7, the first molecularly defined autosomal‐dominant risk factor for any hematological neoplasm, is inherited in a dominant fashion, we determined the incidence of the pP‐7 carrier state in a Japanese population, and compared the frequency of pP‐7‐specific paraproteins and the pP‐7 carrier state in Japanese and German patients with MGUS/MM. Peripheral blood from 111 Japanese patients with MGUS/MM and 278 healthy blood donors was analyzed for the pP‐7 carrier state by isoelectric focusing and for pP‐7‐specific antibodies by ELISA. The Japanese group was compared with 252 German MGUS/MM patients and 200 healthy controls. Five of 111 (4.5%) Japanese and 35/252 (13.9%) German IgA/IgG MGUS/MM patients had a pP‐7‐specific paraprotein (P = 0.009). The prevalence of healthy pP‐7 carriers in the Japanese study group was 1/278 (0.36%), whereas it was 4/200 in the German group (P = 0.166). The relative risk for pP‐7 carriers developing MGUS/MM had an odds ratio of 13.1 in the Japanese and 7.9 in the German group. In conclusion, the fraction of pP‐7 carriers with a pP‐7‐specific paraprotein is lower among Japanese than in German patients with MGUS/MM, but pP‐7 carriers in both ethnic groups have a high risk of developing MGUS/MM. (Cancer Sci 2011; 102: 565–568)

Paratarg-7, a frequent autoantigenic target, and all other autoantigenic targets of human paraproteins molecularly defined to date are hyperphosphorylated in the respective patients compared with healthy controls, suggesting that hyperphosphorylation of autoantigenic paraprotein targets is a general mechanism underlying the pathogenesis of these paraproteins. We now show that hyperphosphorylation of paratarg-7 occurs because of an additional phosphorylation of Ser17, which is located within the paraprotein-binding epitope. Coimmunoprecipitation identified phosphokinase C ζ (PKCζ) as the kinase responsible for the phosphorylation of most, and phosphatase 2A (PP2A) as the phosphatase responsible for the dephosphorylation of all hyperphosphorylated autoantigenic targets of paraproteins. Single-nucleotide polymorphisms (SNPs) or mutations of PKCζ and PP2A were excluded. However, PP2A was inactivated by phosphorylation of its catalytic subunit at Y307. Stimulation of T cells from healthy carriers of wild-type paratarg-7 induced a partial and transient hyperphosphorylation between days 4 and 18, which was maintained by incubation with inhibitors of PP2A, again indicating that an inactivation of PP2A is responsible for the hyperphosphorylation of autoantigenic paraprotein targets. We conclude that the genetic defect underlying the dominantly inherited hyperphosphorylation of autoantigenic paraprotein targets is not in the PP2A itself, but in genes or proteins controlling PP2A activity by phosphorylation of its catalytic subunit.

We recently described paratarg-7 (P-7), a protein of unknown function, as the target of 15% of immunoglobulin A (IgA) and IgG paraproteins in monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma. To determine the frequency of P-7 as a paraprotein target in IgM-MGUS and Waldenström macroglobulinemia (WM), sera from patients with IgM-MGUS/WM were tested for reactivity with recombinant P-7 by enzyme-linked immunoabsorbent assay. The specificity of the paraprotein-mediated reaction was shown by absorption studies and cloning of the respective B-cell receptor. The paraproteins of 18 (9 WM and 9 IgM-MGUS) of 161 patients (11%) reacted with P-7. Isoelectric focusing and phosphatase treatment showed that P-7 was hyperphosphorylated (pP-7) in all patients with an anti-P-7-specific IgM paraprotein tested. Because only 4 of 200 healthy controls (2%) were carriers of pP-7, pP-7 carrier state is associated with a significantly increased risk (odds ratio = 6.2; P = .001) for developing IgM-MGUS/MW. Family analyses showed that the pP-7 carrier state is inherited as a dominant trait. After IgA/IgG-MGUS and multiple myeloma, IgM-MGUS/WM is the second neoplasia associated with pP-7 carrier state. The dominant inheritance of pP-7 explains cases of familial IgM-MGUS/WM and enables the identification of family members at increased risk.

Abstract Abstract 2826 Background: The addition of rituximab to CHOP-21 significantly improved clinical outcome in elderly patients with DLBCL (Coiffier et al., 2002). In young patients, the MInT trial, where young good-prognosis patients were randomized to receive a CHOP-like regimen or the same CHOP-like regimen plus rituximab, had to be stopped early because of superiority of the rituximab arm, and results were published with a median follow-up of 34 months (Pfreundschuh et al., Lancet Oncology 2006;379–91). Objective: Because the MInT study was the first study to show a survival benefit of the addition of rituximab to a CHOP-like regimen in young good-prognosis patients, it is important to analyze the effect of different chemotherapy regimens on long-term outcome. Methods: In a phase III intergroup study with participating cooperative groups from 18 countries, previously untreated young (18-60 years) patients with good-prognosis DLBCL (age-adjusted IPI 0 or 1, stages II-IV and stage I with bulky disease) were randomized to receive 6 cycles of a CHOP-like regimen (CHEMO) or the same chemotherapy plus rituximab 375 mg/m2, given on day 1 of each 3-weekly regimen and on days 1, 22, 43, 64, 85 and 106 of the 2-week regimens, respectively (R-CHEMO). Radiotherapy (30-40 Gy) was planned to sites of initial bulky disease and/or extranodal involvement. The primary endpoint was event-free survival (EFS) with events defined as failure to achieve complete remission, progressive disease, relapse, death or additional (unplanned) therapy. Results: Between 05/2000 and 10/2003 a total of 823 patients were recruited of whom 396 were allocated to receive CHOP-21, 361 to CHOEP-21, 34 to MACOP-B, and 32 to PMitCEBO with or without rituximab. Patients`characteristics were not different between the treatment arms with the exception that patients in the MACOP-B and R-MACOP-B arm had a more favorable prognostic profile. Toxicity, incidence of adverse events and severe adverse events in the different CHEMO and the R-CHEMO arms were not significantly different. After a median observation time of 70 (0.03-117) months, the 6-year EFS rates of patients assigned to CHEMO only were 50.4%, 60%, 41.7%, and 78.6% for CHOP-21, CHOEP-21, PMitCEBO, and MACOP-B, respectively. In an adjusted multivariate Cox regression model for EFS restricted to CHEMO patients, only the CHOEP-21 hazard ratio (HR) was significant (HR=0.73; p=0.05) compared to CHOP-21, while the hazard ratios of the different chemotherapies were not significantly different for PFS and OS (6 year PFS-rates: 60.2%, 64.8%, 67.5%, 86.2%; and 6 year OS-rates: 78.8%, 80.2%, 65.5%, and 100.0%, respectively). In patients assigned to R-CHEMO, 6-year EFS rates were 74.9%, 75%, 36.5%, and 86.7% for CHOP-21, CHOEP-21, PMitCEBO and MACOP-B, respectively. Likewise, PMitCEBO patients tended to have lower PFS (6-year rates: 79.1%, 81.9%, 58.9, and 86.7%, respectively) and OS (6-year rates: 91.9%, 89.4%, 80.0 and 94.1%, respectively). The poor outcome after R-PMitCEBO in contrast to R-CHOP was confirmed by multivariable Cox regression restricted to R-CHEMO and adjusting for aaIPI and bulky disease. Hazard ratio of PMitCEBO was significant for EFS (HR 4.35, p<0.001) and PFS (HR 3.62, p=0.002), with a strong trend for OS (HR 3.11, p=0.073). Conclusion: While the addition of rituximab to CHOP-like regimens usually results in reduced differences between chemotherapy regimens (“chemo-equalizer” effect, e.g. disappearance of the superiority of CHOEP over CHOP after the addition of rituximab), combination of rituximab with some regimens might result in an unexpectedly poor outcome. Therefore, rituximab should not be combined with regimens other than CHOP outside randomized trials. Supported by Roche, Deutsche Krebshilfe and KML. Disclosures: Jäger: Roche: Honoraria, Research Funding. Pettengell:Roche: Honoraria. Pfreundschuh:Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees; GSK: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees.

Background: Antigenic targets of paraproteins in monoclonal gammopathy of undetermined significance (MGUS) and multiple Myeloma (MM) might play a role in the pathogenesis of these neoplasms by chronic antigenic stimulation. However, very few antigens have been identified, of which most were specific for one individual paraprotein only. In contrast, we recently described paratarg-7 (P-7), a protein of unknown function which is expressed in all human tissues as the target of 15% of IgA and IgG paraproteins in MGUS and MM (Grass et al. Lancet Oncology 2009; 10: 950-956). MGUS/MM patients with P-7 specific paraproteins all carry a hyperphosphorylated variant of P-7 (pP-7), which is inherited in a dominant fashion, explaining pP7-posistive cases of familial MGUS/MM. pP-7 is the first molecularly defined autosomal-dominant risk factor for MGUS/MM and is associated with the highest odds ratio (7.9) of all risk factors for MGUS/MM known to date. Since not all cases of familial MGUS/MM have a P-7 specific paraprotein, we set out to identify the antigenic targets of paraproteins in cases of familial MGUS/MM that are not carriers of pP-7. Methods: The sera of 28 members of a family with familial MGUS/MM (Lynch et al. N Engl J Med 2008;359:152-157) were tested for antibody reactivity against antigens represented in a fetal brain derived protein macroarray using a modified SEREX approach (Preuss et al. International J. Cancer 2009;125, 656-661). Results: Sera from 28 family members were analyzed. The sera of all 6 family members affected by MGUS (n=3) and MM (n=3) reacted with paratarg-8, which is encoded by the ATG13 gene, a member of the “autophagy regulatory complex” family of genes. The titers ranged from 1:10 7 to 1:10 8 . No antibody reactivity was detected in the sera of non-affected family members nor in the paraproteins from >300 other patients tested. Conclusions: The paraproteins of members affected by familial MGUS/MM are directed against family-specific antigenic targets, suggesting that the genetic background shared by these patients entertains a chronic auto-immune response. Paratarg-7 and paratarg-8 are the first family-specific antigens that have been molecularly defined to date. Whether the antigen/paraprotein interaction is an epiphenomeon or invovled in the pathogenesis of familial cases of MGUS/MM can now be addressed using specific molecular tools. Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1924.

Abstract Abstract 111 Background: The addition of rituximab to CHOP-21 significantly improved clinical outcome in elderly patients with DLBCL (Coiffier et al., 2002). The MInT trial, randomized young good-prognosis patients to receive a CHOP-like regimen or the same CHOP-like regimen plus rituximab, and was stopped early because of superiority of the rituximab arm, and results were published with a median follow-up of 34 months (Pfreundschuh et al., Lancet Oncology 2006; 379-91). Objective: Because the MInT study was the first study to show a survival benefit with the addition of rituximab to a CHOP-like regimen in young good-prognosis patients, extended follow-up is important to determine whether the survival benefit is maintained over time and whether a definitive effect on cure rates can be shown. Methods: In a phase III intergroup study with participating cooperative groups from 18 countries, previously untreated patients (18-60 years) with low-risk DLBCL (age-adjusted IPI 0 or 1, stages II-IV and stage I with bulky disease) were randomized to receive 6 cycles of a CHOP-like regimen (CHEMO) or the same chemotherapy plus rituximab 375 mg/m2, given on day 1 of each 3-week regimen and on days 1, 22, 43, 64, 85 and 106 of the 2-week regimens, respectively (R-CHEMO). Radiotherapy (30-40 Gy) was planned to sites of initial bulky disease and/or extranodal involvement. The primary endpoint was event-free survival (EFS) with events defined as failure to achieve complete remission, progressive disease, relapse, death or additional therapy. The trial was powered to show a 10% difference in EFS rate after 3 years. Results: Between 05/2000 and 10/2003 a total of 823 patients were recruited of whom 396 were allocated to receive CHOP-21, 361 to CHOEP-21, 34 to MACOP-B, and 32 to PMitCEBO with or without rituximab. Toxicity, incidence of adverse events and severe adverse events in the CHEMO and the R-CHEMO arms were not significantly different. After a median follow-up of 70 (0.03-117) months, patients assigned to chemotherapy and rituximab had increased 6-year event-free survival compared with those assigned to chemotherapy alone (74.0% [95% CI 69.0–78.3] vs 55.7% [50.3-60.8]; log-rank p<0·0001), increased 6-year progression-free survival (79.9% [75.1 - 83.8%] vs 63.8% [58.2-68.8]; log-rank p<0.001) and increased overall survival (89.8% [86.0-92.6] vs 80.0% [75.3-83.9; log rank p=0.001). In a multivariate analysis event-free survival was affected by the addition of rituximab (hazard ratio [HR] 0.49, p< 0.001), age-adjusted IPI (HR 1.73, p<0.001), and bulky disease (HR 1.43, p=0.004). Similar effects were observed for OS, while PFS was affected by treatment arm (HR 0.49, p<0.001) and age-adjusted IPI (HR 1.8, p<0.001). As a consequence, a very favorable subgroup (aaIPI=0, no bulky) can be distinguished from a less favorable subgroup (aaIPI=1 and/or bulky disease) among good-prognosis patients treated with rituximab. There were 10 late (>60 months) events after CHEMO (61.4 to 96.1 months), including 4 in the very favorable subgroup, while all 8 late events (67.5 to 105.7 months) after R-CHEMO occurred in the less favorable subgroup only, and none in the very favorable subgroup. Conclusion: Addition of rituximab to a CHOP-like regimen leads to a significant improvement of the outcome in young patients with good-prognosis diffuse large B-cell lymphoma, with significant survival benefit maintained during a 6-year follow-up. However, except in the very favorable subgroup after R-CHEMO, late relapses after 5 years occur. While reduction of treatment in a randomized study like the FLYER trial of the DSHNHL is justified, further progress, e.g. by dose densification (UNFOLDER trial of the DSHNHL) and/ or dose escalation is still warranted for the less favorable subgroup. Supported by Roche, Deutsche Krebshilfe and KML. Disclosures: Pfreundschuh: Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees; GSK: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees. Trneny:Roche: Honoraria, Research Funding. Walewski:Roche: Honoraria, Research Funding. Pettengell:Roche: Honoraria. Jäger:Roche: Honoraria, Research Funding. Lopez-Guillermo:Roche: Consultancy.

Abstract Antigenic targets of monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM) paraproteins might play a role in the pathogenesis of these neoplasms. By screening a commercially available recombinant human cDNA expression macroarray we identified paratarg-7 as the antigenic target of the paraprotein from 14% (35/252) of all patients analyzed (Preuss et al. Int J Cancer 2009). The high frequency of hyperphosphorylated paratarg-7 as the antigenic target of paraproteins from MM/MGUS patients suggests that the modified protein is involved in the development of sporadic and familial MGUS/MM by acting as a chronic antigenic stimulus for the respective B-cell clones. With a relative risk of 7.9, the carrier state of hyperphosphorylated paratarg-7 (pP-7) is the strongest risk factor for the development of MGUS/MM. Moreover, the analysis of consanguineous relatives of MM/MGUS patients with an anti-paratarg-7 specific paraprotein showed that pP7 is inherited in a dominant fashion (Grass et al., Lancet Oncology, 2009). Here we present data showing that the hyperphosphorylation of paratarg-7 is due to an additional phosphorylation of this protein at the identical phosphorylation site when compared to normal paratarg-7. We identified protein kinase C zeta as responsible for this hyperphosphorylation which specifically occurs on Ser17 which is part of the 15 amino acid region identified as the paraprotein-binding epitope in all paratarg-7-immunopositive patients. In additional experiments no DNA modification of PKCzeta was detected. As shown by Western blot experiments and quantitative PCR no overexpression or copy number variation of PKCzeta was shown, suggesting that other not yet identified enzyme(s) must be involved in the process of paratarg-7 hyperphosphorylation or the maintenance of the hyperphosphorylated state. Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4772.

Abstract Abstract 4085 Background: Hyperphosphorylated paratarg-7 (pP-7) is the target of paraproteins in 15% of patients with MGUS/MM (Preuss et al. Int J Cancer 2009; 125:656-61). Carriers of pP-7 have an 8-times increased risk to develop IgA/IgG-MGUS and multiple myeloma (Grass et al., Lancet Oncology 2009; 10:950-956) and a 6.5 times increased risk to develop IgM-MGUS and Waldenström′s macroglobulinemia (Grass et al., Blood 2009;114:1513s). Analysis of affected families showed that pP-7 is inherited in a dominant fashion. Thus, pP-7 is the first molecularly defined autosomal-dominant risk factor for any hematological neoplasm. Objective: Since paratarg-7, a frequent target of paraproteins in patients with MGUS/MM is hyperphosphorylated and inherited in a dominant fashion we extended our studies to investigate the prevalence of further antigenic targets and their phosphorylation state. Methods: Sera of MGUS/MM patients and relatives of affected families were tested for antibody reactivity against antigens represented in a fetal brain derived protein macroarray using a modified SEREX approach (Preuss et al. International J. Cancer 2009;125, 656–661). Lysates of peripheral blood from patients, family-members and controls were tested by gel electrophoresis and isoelectric focusing before and after phosphatase treatment. Results: Analysis of 3 families with multiple members affected by MGUS and MM revealed that the antigenic targets of paraproteins from affected members of a given family are identical: 2 families shared paratarg-7 and 1 family shared paratarg-8 as the family-typic paraprotein antigen. Paratarg-8 is encoded by the ATG13 gene, a member of the „autophagy regulatory complex“ family of genes. Paratarg-8 showed no mutations or polymorphisms in patients compared to controls. However, IEF before and after phosphatase treatment showed that paratarg-8 is hyperphosphorylated (pP-8) in the affected family members compared to healthy controls and that pP-8 carrier state is also inherited in a dominant fashion. This finding prompted us to check previously identified paraprotein targets for hyperphosphorylation, which, in addition to paratarg-7 and paratarg-8 was possible for paratarg 2, 5, 6, 9, 10, 11. In all 8/8 cases, IEF before and after phosphatase treatment revealed that the patients were carriers of a hyperphosphorylated version of their paraprotein target compared to healthy controls. Conclusions: The paraproteins of members affected by familial MGUS/MM are directed against family-specific antigenic targets, suggesting that the genetic background shared by these patients contains a chronic auto-immune response. Paratarg-7 and paratarg-8 are the first family-typic antigens that have been molecularly defined to date. The fact that all antigenic targets of paraproteins molecularly defined to date are hyperphosphorylated in patients compared to healthy controls implies a significant role of the hyperphosphorylation state in these neoplasms. Analysis of the T-cell response against normo- and hyperphosphorylated paraprotein targets in affected and non-affected family members is underway as are genome-wide association to determine the SNP or mutation which is associated with the hyperphosphorylation of paraprotein targets. Disclosures: Lynch: State of Nebraska LB595 support: Research Funding; Charles F. and Mary C. Heider Chair at Creighton University.: Research Funding.

Abstract Background: Antigenic targets of paraproteins in monoclonal gammopathy of undetermined significance (MGUS), multiple Myeloma (MM) and Waldenstrom's macroglobulinemia (WM) might play a role in the pathogenesis of these neoplasms by chronic antigenic stimulation, but very few have been identified, of which most were specific for one individual paraprotein only. In contrast, we recently described paratarg-7, a protein of unknown function which is expressed in all human tissues as the target of 15% of IgA and IgG paraproteins in MGUS and MM. Mutations or polymorphisms of paratarg-7 were not found, but hyperphosphorylation was detected in 35/252 (14%) of MGUS/MM patients and in 18/161 (11%) of WM patients, all of whom had an anti-paratarg-7 specific paraprotein. Analysis of 16 families demonstrated that hyperphosphorylated paratarg-7 is inherited in a dominant fashion and carriers of hyperphosphorylated paratarg-7 have an increased risk of developing MGUS/MM/WM (odds ratio 7.9; 95% CI: 2.8-22.6, p=0.0001). The aim of this study was to identify chromosome regions linked to hyperphosphorylated paratarg-7, a frequent antigenic target of paraproteins in MGUS/MM/WM. Methods: Serum and peripheral blood cells were obtained from 90 relatives of 16 families of patients with MGUS/MM/WM. We used a high density, single nucleotide polymorphism genotyping assay, the Illumina SentrixR BeadChip Array, the HumanHap300-Duo Bead Chip, comprising 318.000 tag single nucleotide polymorphisms to perform a genome-wide linkage analysis of 48 relatives of 4 families by filtering 23211 SNP markers with a spacing of > 100kb and an allele frequency > 0.15. Additionally, we carried out non-parametric as well as parametric analyses based on the genotypes of different microsatellite markers. Results: We found strong evidence for parametric linkage (full penetrant autosomal dominant model; disease marker allele frequency=0.02; LOD= 5.9) and non-parametric linkage (Zmean= 5.1; P<10−5) on chromosome 4q35. Conclusions: Hyperphosphorylated paratarg-7 is a highly significant risk factor for MGUS, WM and MM, with the highest odds ratio of any risk factor reported to date for these diseases. We report the first genome-wide linkage study of a new molecularly defined risk factor of MGUS//MM/WM and novel loci on 4q35 linked to hyperphosphorylated paratarg-7. Identification of novel causative genes for MGUS/MM/WM will now advance our understanding of the pathogenesis in these diseases. Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1169.