Cardiovascular diseases after high-dose chemotherapy and autologous stem cell transplant for lymphoma: A Danish population-based study

Cardiovascular diseases, especially congestive heart failure (CHF), are known complications of anthracyclines, but the risk for patients undergoing high-dose chemotherapy and autologous stem cell transplant (HDT-ASCT) is not well established. With T-cell therapies emerging as alternatives, studies of long-term complications after HDT-ASCT are warranted. Danish patients treated with HDT-ASCT for aggressive lymphoma between 2001 and 2017 were matched 1:5 on sex, birth year and Charlson comorbidity score to the general population. Events were captured using nationwide registers. A total of 787 patients treated with HDT-ASCT were identified. Median follow-up was 7.6 years. The risk of CHF was significantly increased in the HDT-ASCT population compared to matched comparators with an adjusted hazard ratio (HR) of 5.5 (3.8-8.1). The 10-year cumulative incidence of CHF was 8.0% versus 2.0% (p < 0.001). Male sex, ≥2 lines of therapy, hypertension and cumulative anthracycline dose (≥300 mg/m2 ) were risk factors for CHF. In a separate cohort of 4089 lymphoma patients, HDT-ASCT was also significantly associated with increased risk of CHF (adjusted HR of 2.6 [1.8-3.8]) when analysed as a time-dependent exposure. HDT-ASCT also increased the risk of other cardiac diseases. These findings are applicable for the benefit/risk assessment of HDT-ASCT versus novel therapies.

ProGraME: A novel flow cytometry algorithm for the diagnosis of low-risk myelodysplastic syndromes in patients with cytopenia

OBJECTIVES

Flow cytometry (FC) is, together with morphology, genetics, and cytogenetics, used in the diagnostic assessment of cytopenia, as its value in evaluating bone marrow dysplasia been highlighted by several studies. However, despite the development of algorithms and guidelines, there is still a lack of standardization of the FC assessment of bone marrow dysplasia.

METHODS

By combining FC, together with morphological analysis and cytogenetic/molecular assessment in a training cohort of 209 patients, we created a novel score, ProGraME, which includes four parameters, each from a different cell lineage (Progenitor cells, Granulocytes, Monocytes, Erythroid precursors), solely based on relevant population gating. Points for ProGraME were attained for: lymphoid precursors ≤5% of all CD34+ cells (1.5 point); a granulocyte-to-lymphocyte side-scatter ratio ≤6 (1 point); a monocyte CD33-CV% ≥ 63 (2 points), and an erythroid precursor CD36-CV% ≥ 65 (2 points).

RESULTS

Using a cutoff of ≥2 as suggestive of dysplasia, ProGraME showed a sensitivity of 91% and a specificity of 81% in the training cohort and 95% and 75%, respectively, in an independent validation cohort of 159 patients. In addition, ProGraME had a very high negative predictive value of 97.1% and 97.8% in the training and validation cohorts, respectively, offering a useful tool for excluding bone marrow dysplasia. Finally, among the 23 CCUS patients that scored positive for dysplasia with ProGraME in the training cohort, 16 of them (69%) carried high-risk mutations, suggesting that FC might help identify early changes of dysplasia.

CONCLUSIONS

ProGraME can potentially optimize the FC diagnosis of low-risk myelodysplasia without minimal requirements of flow analysis other than accurate population gating.

Humoral and cellular immune responses after three or four doses of BNT162b2 in patients with hematological malignancies

OBJECTIVES

Initial responses to coronavirus disease 2019 vaccination are impaired in patients with hematological malignancies. We investigated immune responses after three or four doses of BNT162b2 in patients with myeloid and lymphoid malignancies compared to controls, and identified risk factors for humoral and cellular nonresponse 1 year after first vaccination.

METHODS

In 407 hematological patients (45 myeloid, 362 lymphoid) and 98 matched controls, we measured immunoglobulin G (IgG) and neutralizing antibodies specific for the receptor-binding domain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at baseline, 3 weeks, 2, 6, and 12 months, and interferon-γ release at 12 months.

RESULTS

In patients with lymphoid malignancies, SARS-CoV-2 receptor-binding domain IgG concentration and mean neutralizing capacity was lower than in controls at all time points. A diagnosis of chronic lymphocytic B-cell leukemia (CLL) or lymphoma was associated with humoral nonresponse at 12 months compared to having multiple myeloma/amyloidosis (p < .001 and p = .013). Compared to controls, patients with lymphoid malignancies had increased risk of cellular nonresponse. A lymphoma diagnosis was associated with lower risk of cellular nonresponse compared to patients with multiple myeloma/amyloidosis, while patients with CLL had comparable response rates to patients with multiple myeloma/amyloidosis (p = .037 and p = .280).

CONCLUSIONS

In conclusion, long-term humoral and cellular immune responses to BNT162b2 were impaired in patients with lymphoid malignancies.

Monocytosis in primary care and risk of haematological malignancies

Monocytosis (≥0.5 × 10⁹ /L in peripheral blood) is the hallmark of chronic myelomonocytic leukaemia (CMML) but may be present in a spectrum of diseases including other haematological malignancies. In the primary care sector, monocytosis is a relatively common finding, but its predictive value for haematological malignancy is unknown. We included 663 184 adult primary care patients from the greater Copenhagen area with one or more differential cell counts registered between 2000 and 2016 and followed them in the extensive nationwide Danish health data registers for 3 years after blood sampling. We used logistic regression to model the risk of haematological malignancy and death following monocytosis. Monocytosis was associated with an increased risk of all types of haematological malignancy with the greatest relative risk increase observed in CMML with an OR of 105.22 (95% confidence interval: 38.27-289.30). Sustained monocytosis (at least two requisitions in 3 months) further increased CMML risk, although the diagnosis was still very rare, that is, observed in only 0.1% of these individuals. Outside the haematological setting, the absolute risk of haematological malignancy associated with monocytosis is low and haematological malignancy should mainly be suspected when monocytosis is sustained or the clinical presentation raises suspicion of malignancy.

Safety, Outcomes, and T-Cell Characteristics in Patients with Relapsed or Refractory MDS or CMML Treated with Atezolizumab in Combination with Guadecitabine

PURPOSE

We hypothesized that resistance to hypomethylating agents (HMA) among patients with myelodysplastic syndrome (MDS) and chronic myelomonocytic leukemia (CMML) would be overcome by combining a programmed death-ligand 1 antibody with an HMA.

PATIENTS AND METHODS

We conducted a Phase I/II, multicenter clinical trial for patients with MDS not achieving an International Working Group response after at least 4 cycles of an HMA ("refractory") or progressing after a response ("relapsed") with 3+ or higher risk MDS by the revised International Prognostic Scoring System (IPSS-R) and CMML-1 or -2. Phase I consisted of a 3+3 dose-escalation design beginning with guadecitabine at 30 mg/m2 and escalating to 60 mg/m2 Days 1 to 5 with fixed-dose atezolizumab: 840 mg intravenously Days 8 and 22 of a 28-day cycle. Primary endpoints were safety and tolerability; secondary endpoints were overall response rate (ORR) and survival.

RESULTS

Thirty-three patients, median age 73 (range 54-85), were treated. Thirty patients had MDS and 3 had CMML, with 30% relapsed and 70% refractory. No dose-limiting toxicities were observed in Phase I. There were 3 (9%) deaths in ≤ 30 days. Five patients (16%) came off study for drug-related toxicity. Immune-related adverse events (IRAE) occurred in 12 (36%) patients (4 grade 3, 3 grade 2, and 5 grade1). ORR was 33% [95% confidence interval (CI), 19%-52%] with 2 complete remission (CR), 3 hematologic improvement, 5 marrow CR, and 1 partial remission. Median overall survival was 15.1 (95% CI, 8.5-25.3) months.

CONCLUSIONS

Guadecitabine with atezolizumab has modest efficacy with manageable IRAEs and typical cytopenia-related safety concerns for patients with relapsed or refractory MDS and CMML.

Socioeconomic position and clinical outcomes in patients with myelodysplastic syndromes: A population-based cohort study

Low socioeconomic position (SEP) may be associated with adverse outcomes in patients with myelodysplastic syndromes (MDS) inherent to for example, delayed diagnosis or reduced treatment intensity, but firm evidence is limited. In this study, we examined the association between SEP and clinical outcomes. We conducted a population-based cohort study (2010-2018) of 2233 Danish patients with MDS. SEP measures included individual-level information on education, cohabitation status and income retrieved from Statistics Denmark. Associations between SEP measures and disease severity at diagnosis were examined using binomial regression analysis. Using time-to-event analysis, we examined the association between SEP measures and treatment with allogeneic stem cell transplantation (allo-HSCT), risk of progression to acute myeloid leukemia (AML), and death. Estimates were adjusted for covariates selected based on direct acyclic graphs and reported with 95% confidence intervals. Patients with a short education were more likely to be transfusion-dependent at diagnosis (RR = 1.25, 95% CI: 1.04-1.45) and more likely to be diagnosed with higher risk MDS according to the International Prognostic Scoring System (RR = 1.29, 95% CI: 1.03-1.62), than patients with a long education. We found no clear association between SEP and risk of progression to AML. In adjusted models, the 1-year risk of dying was higher in patients with short versus long education (RR = 1.34, 95% CI: 1.08-1.65), in patients with low versus high income (RR = 1.42, 95% CI: 1.14-1.77), and among patients who lived alone compared to those who lived with a partner (RR = 1.15, 0.98-1.35). These associations persisted after 3 years and 5 years of follow-up. Notably, patients with a short education had a markedly lower rate of undergoing treatment with allo-HSCT compared to patients with a long education (HR = 0.51, 95% CI: 0.31-0.84). In conclusion, low SEP and especially short education, were poor prognostic factors for adverse clinical outcomes among patients with MDS.

Humoral response to two doses of BNT162b2 vaccination in people with HIV

BACKGROUND

People with HIV (PWH) are at increased risk of severe COVID-19. We aimed to determine humoral responses in PWH and controls who received two doses of BNT162b2.

METHODS

In 269 PWH and 538 age-matched controls, we measured IgG and neutralizing antibodies specific for the receptor-binding domain of SARS-CoV-2 at baseline, 3 weeks and 2 months after the first dose of BNT162b2.

RESULTS

IgG antibodies increased from baseline to 3 weeks and from 3 weeks to 2 months in both groups, but the concentrations of IgG antibodies were lower in PWH than that in controls at 3 weeks and 2 months (p = 0.025 and <0.001), respectively. The IgG titres in PWH with a humoral response at 2 months were 77.9% (95% confidence interval [62.5%-97.0%], age- and sex-adjusted p = 0.027) of controls.

CONCLUSIONS

Reduced IgG antibody response to vaccination with BNT162b2 was found in PWH, and thus increased awareness of breakthrough infections in PWH is needed.

Pre-treatment health-related quality of life parameters have prognostic impact in patients >65 years with newly diagnosed mantle cell lymphoma: The Nordic Lymphoma Group MCL4 (LENA-BERIT) experience

Mantle cell lymphoma (MCL) is a rare, often aggressive type of B-cell lymphoma with poor survival and no cure. Cancer and cancer treatment has a negative impact on health-related quality of life (HRQOL) both during active disease and in the long term, and improvement of HRQOL is a crucial objective of cancer therapy in older patients and no curative intent. Baseline HRQOL has in other lymphoma populations been shown to be predictive of outcome. Here, we explored HRQOL, and its association with survival, by the EORTC QLQ-C30 questionnaire, before, during and after chemotherapy in a patient cohort with MCL, treated within the NLG-MCL4 trial, designed to evaluate the addition of lenalidomide (LEN) to rituximab-bendamustine (R-B) as first-line treatment. Fifty-one patients were enrolled, median age was 71 years (range 62-84), 37 were men (73%). Pre-treatment HRQOL was similar to scores from the reference population with healthy individuals. During treatment, HRQOL deteriorated, but reverted to the same level as the reference population after treatment. There was a correlation between physical function (p = 0.001) and role function (p = 0.006) at baseline and WHO performance status, but not with other clinical or genetic prognostic factors. None of the baseline factors were predictive for treatment related to HRQOL in this cohort. Pre-treatment physical (p = 0.011) and role function (p = 0.032) were independent factors associated with overall survival, and physical function (p = 0.002) was also associated with progression free survival. These findings may possibly be used to design support during treatment and improve rehabilitation. Further investigations are needed for assessment of long-term HRQOL.

Serum proteome modulations upon treatment provides biological insight on response to treatment in relapsed mantle cell lymphoma

Background

The possibility to monitor patient's serum proteome during treatment can provide deepened understanding of the biology associated with response to specific drugs. Non‐invasive serum sampling provides an opportunity for sustainable repetitive sampling of patients, which allows for more frequent evaluation of the biological response and enhanced flexibility in treatment selection in contrast to tissue biopsies.

Aim

To pin‐point biologically relevant changes in pre‐ and on‐treatment serum proteome samples in relapsed mantle cell lymphoma (MCL) patients, leading to insight into mechanisms behind response to treatment in sub‐groups of patients.

Methods

Pre‐ and on‐treatment serum samples from relapsed MCL patients treated with a triple combination therapy of rituximab, ibrutinib and lenalidomide were available for the study, together with detailed clinicopathological information. A microarray technology targeting 158 serum proteins using 371 antibody‐fragments was used to compare the serum proteome at the two time‐points.

Results

Proteins modulated by the treatment were shown to be associated to a MCL sub‐group with ATM/TP53 alterations, which emphasizes the importance of treatment stratification. Absolute values of serum protein levels in on‐treatment samples were highly variable and showed no correlation to outcome. To circumvent the challenge of variability in absolute serum protein levels, the velocity of change of individual serum proteins was used to identify proteins associated with clinical response. Increased values of TGF‐β1, CD40 and complement component 4 comparing pre‐ and on‐treatment samples were associated with remaining minimal residual disease (MRD) and increased BTK was associated with short progression‐free survival (PFS).

Conclusion

We show that the genetic sub‐type of MCL affects the biological response to treatment in serum and that the change in defined serum proteins reveals the biology associated with clinical response.

Risk of new malignancies among patients with CLL treated with chemotherapy: results of a Danish population-based study

Patients with chronic lymphocytic leukaemia (CLL) have an increased risk of new malignancies. However, limited data have been published about the impact of CLL treatment on this risk. Here we followed a Danish population-based cohort of CLL patients for risks of new malignancies. Patients in the Danish CLL registry (2008-2017) were included. Up to 50 CLL-free matched comparators were identified. First-line treatment was categorized into four groups; bendamustine, chlorambucil, fludarabine or other. Patients were followed from CLL diagnosis for individual types of malignancy. Adjusted hazard ratios (HR) for new malignancies and 95% confidence intervals (95% CI) were calculated. Overall, 4286 CLL patients and 214 150 controls developed 594 and 20 565 new malignancies respectively. Risk of new malignancies was increased for CLL patients. Chemotherapy treatment was registered for 1064 (25%) patients with CLL. Chemotherapy was associated with increased HR (1·51, 95% CI: 1·3-1·8) of any new malignancy. Specifically, fludarabine was associated with an increased risk of myelodysplastic syndrome (MDS) (HR 4·93, 95% CI: 1·2-19·8). Patients with CLL are at increased risk of other haematological and solid malignancies compared to the general population. Chemotherapy exposure is associated with increased risk of second malignancies and fludarabine is associated with increased risk of MDS.

p53 is associated with high-risk and pinpoints TP53 missense mutations in mantle cell lymphoma

Survival for patients diagnosed with mantle cell lymphoma (MCL) has improved drastically in recent years. However, patients carrying mutations in tumour protein p53 (TP53) do not benefit from modern chemotherapy-based treatments and have poor prognosis. Thus, there is a clinical need to identify missense mutations through routine analysis to enable patient stratification. Sequencing is not widely implemented in clinical practice for MCL, and immunohistochemistry (IHC) is a feasible alternative to identify high-risk patients. The aim of the present study was to investigate the accuracy of p53 as a tool to identify patients with TP53 missense mutations and the prognostic impact of overexpression and mutations in a Swedish population-based cohort. In total, 317 cases were investigated using IHC and 255 cases were sequenced, enabling analysis of p53 and TP53 status among 137 cases divided over the two-cohort investigated. The accuracy of predicting missense mutations from protein expression was 82%, with sensitivity at 82% and specificity at 100% in paired samples. We further show the impact of p53 expression and TP53 mutations on survival (hazard ratio of 3·1 in univariate analysis for both), and the association to risk factors, such as high MCL International Prognostic Index, blastoid morphology and proliferation, in a population-based setting.

Angiotensinogen promoter methylation predicts bevacizumab treatment response of patients with recurrent glioblastoma

Patients with recurrent glioblastoma achieving response to bevacizumab combined with chemotherapy have clinical improvement and prolonged survival. High gene expression of angiotensinogen (AGT) is associated with a poor bevacizumab response. Because AGT expression is epigenetically regulated, we aimed to investigate whether AGT promoter methylation in tumor tissue predicts response to bevacizumab combination therapy in patients with recurrent glioblastoma. The study included 159 patients with recurrent glioblastoma, treated with bevacizumab combination treatment (training cohort, n = 77; validation cohort, n = 82). All patients could be evaluated for treatment response and biomarkers. DNA methylation of 4 CpG sites in the AGT promoter was measured using pyrosequencing. A model for nonresponse was established using logistic regression analysis. In the training cohort, lower methylation of each of the four CpG sites in the AGT promoter was significantly associated with nonresponse (all P < 0.05). Moreover, the mean methylation level of all four CpG sites was associated with an increased likelihood of not achieving response to bevacizumab combination therapy (twofold decrease: odds ratio = 3.01; 95% confidence interval: 1.41-6.44; P = 0.004). We developed a model for nonresponse in the training cohort, where a threshold of mean AGT promoter methylation levels was set to below 12%. The model could predict bevacizumab nonresponse with 96% specificity. Importantly, this predictor was also significantly associated with nonresponse in the validation cohort (P = 0.037). Taken together, our findings suggest that low AGT promoter methylation in tumor tissue predicts nonresponse to bevacizumab combination treatment in patients with recurrent glioblastoma. We have, thus, established and successfully validated a predictor for nonresponse that can be used to identify patients who will not benefit from bevacizumab combination therapy.

Epidemiology of chronic red-cell transfusion recipients in Sweden and Denmark-a 10 year follow-up study

BACKGROUND AND OBJECTIVES

Chronic red-cell transfusions may be an indispensable part of patient treatment and may require early intervention to avoid adverse transfusion effects. The population of chronic transfusion recipients including common diagnoses and survival remains poorly characterised. Thus, the objective was to examine the complete range of chronic transfusion recipients, including demographic and patient characteristics and survival.

MATERIALS AND METHODS

All patients who received their first transfusion in Sweden or Denmark from January 1, 2002 to December 31, 2010 were followed up for subsequent transfusion episodes until December 31, 2012. Data on patient characteristics at time of the first and subsequent transfusions were retrieved from the national registers. We estimated the proportion of transfused patients who experienced 20 or more red-cell transfusion episodes (with an episode defined as all transfusions received 4 days or less apart) and characterised this patient population with respect to diagnoses, demographics and survival.

RESULTS

Among 893 117 first time red-cell transfusion recipients, 6157 (0·7%) experienced 20 or more episodes in total. The most common diagnoses among these patients were haematologic malignancies followed by non-haematologic malignancies and non-malignant blood and immune system related diseases. On average, chronically transfused patients had a median survival of less than 1 year following their 20th transfusion episode.

CONCLUSION

This study provides an overview of patient characteristics related to repeat red-cell transfusions and of the amount of red-cell transfusion episodes administered during a 10-year period in two countries. Patients who become chronically transfused suffer from diseases with poor prognosis.

Long-term clinical outcomes of patients with hematologically unexplained cytopenia after routine assessment: A single center study

OBJECTIVE

We investigated mortality and long-term development of malignant hematological disease, cancer, liver-, renal-, and rheumatic disease in patients with unexplained cytopenia (UC).

METHODS

We screened all patients referred to the outpatient clinic at the Department of Hematology, Rigshospitalet, Copenhagen, with a suspected myeloid neoplasm from June 2009 to the end of 2012. Through registry linkage, we obtained information on hospital-based ICD-10 diagnoses and survival. We estimated cumulative incidences of disease and hazard ratios of all-cause mortality using the Aalen-Johansen estimator and Cox regression. We compared incidences and mortality with a control cohort.

RESULTS

Among 1820 referrals, 221 had UC. The UC group had a 5-year cumulative incidence of malignant hematological disease of 8.91% (CI 95%: 4.98-12.84) compared to 0.93(CI 95%: 0.32-1.55) in the matched controls. In addition, UC patients had higher incidences of cancer, liver, and rheumatic disease. Mortality was higher in UC patients compared to the matched controls with a HR of 1.43 [P = 0.038, CI 95%: 1.02-2.00] adjusted for comorbidity, sex, and age. Most of the mortality and morbidity were ascribed to patients 50 years or older.

CONCLUSIONS

Unexplained cytopenia patients had a higher incidence of malignant hematological-, cancer-, liver-, and rheumatic disease and increased mortality compared to the general population.

Twin DNA Methylation Profiling Reveals Flare-Dependent Interferon Signature and B Cell Promoter Hypermethylation in Systemic Lupus Erythematosus

OBJECTIVE

Systemic lupus erythematosus (SLE) has limited monozygotic twin concordance, implying a role for pathogenic factors other than genetic variation, such as epigenetic changes. Using the disease-discordant twin model, we investigated genome-wide DNA methylation changes in sorted CD4+ T cells, monocytes, granulocytes, and B cells in twin pairs with at least 1 SLE-affected twin.

METHODS

Peripheral blood obtained from 15 SLE-affected twin pairs (6 monozygotic and 9 dizygotic) was processed using density-gradient centrifugation for the granulocyte fraction. CD4+ T cells, monocytes, and B cells were further isolated using magnetic beads. Genome-wide DNA methylation was analyzed using Infinium HumanMethylation450K BeadChips. When comparing probes from SLE-affected twins and co-twins, differential DNA methylation was considered statistically significant when the P value was less than 0.01 and biologically relevant when the median DNA methylation difference was >7%. Findings were validated by pyrosequencing and replicated in an independent case-control sample.

RESULTS

In paired analyses of twins discordant for SLE restricted to the gene promoter and start region, we identified 55, 327, 247, and 1,628 genes with differentially methylated CpGs in CD4+ T cells, monocytes, granulocytes, and B cells, respectively. All cell types displayed marked hypomethylation in interferon-regulated genes, such as IFI44L, PARP9, and IFITM1, which was more pronounced in twins who experienced a disease flare within the past 2 years. In contrast to what was observed in the other cell types, differentially methylated CpGs in B cells were predominantly hypermethylated, and the most important upstream regulators included TNF and EP300.

CONCLUSION

Hypomethylation of interferon-regulated genes occurs in all major cellular compartments in SLE-affected twins. The observed B cell promoter hypermethylation is a novel finding with potential significance in SLE pathogenesis.

Dual inhibition of DNMTs and EZH2 can overcome both intrinsic and acquired resistance of myeloma cells to IMiDs in a cereblon-independent manner

Thalidomide and its derivatives, lenalidomide and pomalidomide (also known as IMiDs), have significantly changed the treatment landscape of multiple myeloma, and the recent discovery of cereblon (CRBN) as their direct biological target has led to a deeper understanding of their complex mechanism of action. In an effort to comprehend the precise mechanisms behind the development of IMiD resistance and examine whether it is potentially reversible, we established lenalidomide‐resistant (‐LR) and pomalidomide‐resistant (‐PR) human myeloma cell lines from two IMiD‐sensitive cell lines, OPM2 and NCI‐H929, by continuous culture in the presence of lenalidomide or pomalidomide for 4–6 months, until acquirement of stable resistance. By assessing genome‐wide DNA methylation and chromatin accessibility in these cell lines, we found that acquired IMiD resistance is associated with an increase in genome‐wide DNA methylation and an even greater reduction in chromatin accessibility. Transcriptome analysis confirmed that resistant cell lines are mainly characterized by a reduction in gene expression, identifying SMAD3 as a commonly downregulated gene in IMiD‐resistant cell lines. Moreover, we show that these changes are potentially reversible, as combination of 5‐azacytidine and EPZ‐6438 not only restored the observed accessibility changes and the expression of SMAD3, but also resensitized the resistant cells to both lenalidomide and pomalidomide. Interestingly, the resensitization process was independent of CRBN. Our data suggest that simultaneous inhibition of DNA methyl transferases and EZH2 leads to an extensive epigenetic reprogramming which allows myeloma cells to (re)gain sensitivity to IMiDs.

Global hypomethylation is an independent prognostic factor in diffuse large B cell lymphoma

Global hypomethylation has been linked to disease progression in several cancers, but has not been reported for Diffuse Large B Cell Lymphoma (DLBCL). This study aimed to assess global methylation in DLBCL and describe its prognostic value. Mean LINE1 methylation, a validated surrogate measure for global methylation, was measured in DNA from 67 tumor biopsies. Additionally, cell-free circulating DNA (cfDNA) in plasma samples from 74 patients was tested to assess the feasibility of global hypomethylation as a biomarker in liquid biopsies. LINE1 methylation was assessed using a commercially available kit, based on pyrosequencing of PCR amplified bisulfite-treated DNA. Global hypomethylation was detected in a subset of cases and was associated with poor overall survival in both tumor biopsies (P = .001) and cfDNA (P = .009). It was the strongest risk factor in multivariate analysis in both biopsies (HR: 10.65, CI: 2.03-55.81, P = .005) and cfDNA (HR: 11.87, CI: 2.80-50.20, P = .001), outperforming conventional clinical risk factors. Finally, hierarchical cluster analyses were performed for the cfDNA samples using previously published gene-specific methylation data. This analysis shows that global hypomethylation co-occurs with other epigenetic abnormalities, including DAPK1 promoter hypermethylation. In conclusion, we have shown that global hypomethylation is strongly associated with poor survival in DLBCL both when present in tumor biopsy DNA and when detected in plasma cfDNA, and has potential for clinical application as a prognostic biomarker.

SOX11 and TP53 add prognostic information to MIPI in a homogenously treated cohort of mantle cell lymphoma--a Nordic Lymphoma Group study

Mantle cell lymphoma (MCL) is an aggressive B cell lymphoma, where survival has been remarkably improved by use of protocols including high dose cytarabine, rituximab and autologous stem cell transplantation, such as the Nordic MCL2/3 protocols. In 2008, a MCL international prognostic index (MIPI) was created to enable stratification of the clinical diverse MCL patients into three risk groups. So far, use of the MIPI in clinical routine has been limited, as it has been shown that it inadequately separates low and intermediate risk group patients. To improve outcome and minimize treatment-related morbidity, additional parameters need to be evaluated to enable risk-adapted treatment selection. We have investigated the individual prognostic role of the MIPI and molecular markers including SOX11, TP53 (p53), MKI67 (Ki-67) and CCND1 (cyclin D1). Furthermore, we explored the possibility of creating an improved prognostic tool by combining the MIPI with information on molecular markers. SOX11 was shown to significantly add prognostic information to the MIPI, but in multivariate analysis TP53 was the only significant independent molecular marker. Based on these findings, we propose that TP53 and SOX11 should routinely be assessed and that a combined TP53/MIPI score may be used to guide treatment decisions.

Splenectomy in two children with autoimmune lymphoproliferative syndrome and massive splenomegaly

Treatment of patients with ALPS has varied but presently there is no consensus about the optimal therapy. Splenectomy is an option but data regarding the postsplenectomy outcome in pediatric ALPS patients remain very limited. We present two children who suffered from anemia and physical discomfort from the large spleen. Both patients underwent uneventful splenectomy and experienced significant improvement in cytopenia, daily activity and well-being. Furthermore the youngest patient showed a significant catch-up growth. We conclude that in selected patients with marked splenomegaly and ALPS, splenectomy may be considered a treatment option.

Engaging the lysosomal compartment to combat B cell malignancies

The combination of rituximab, a type I anti-CD20 mAb, with conventional chemotherapy has significantly improved the outcome of patients with B cell malignancies. Regardless of this success, many patients still relapse with therapy-resistant disease, highlighting the need for the development of mAbs with higher capacity to induce programmed cell death. The so-called type II anti-CD20 mAbs (e.g., tositumomab) that trigger caspase-independent B cell lymphoma cell death in vitro and show superior efficacy as compared with rituximab in eradicating target cells in mouse models are emerging as the next generation of therapeutic anti-CD20 mAbs. In this issue of the JCI, Ivanov and colleagues identify the lysosomal compartment as a target for type II mAbs (see the related article beginning on page 2143). These data encourage the further clinical development of type II mAbs as well as other lysosome-targeting drugs in the treatment of B cell malignancies.

A novel splice mutation in the TP53 gene associated with Leydig cell tumor and primitive neuroectodermal tumor

A 20-month-old boy presented with precocious puberty due to a Leydig cell tumor, and at the age of 6 years with a primitive neuroectodermal brain-tumor (PNET). A novel splice site mutation of the TP53-gene, likely to be associated with a nonfunctional protein, was found in the proband, his father and younger sister, but only the proband has so far developed malignancy. The clinical phenotype in the boy is suggestive of Li-Fraumeni syndrome, but the family does not strictly conform to the canonical definition.

MicroRNAs and cancer

MicroRNAs (miRNAs) are a recently discovered group of small RNA molecules involved in the regulation of gene expression. Analogously to mRNAs, the non-protein-encoding pri-miRNAs are synthesized by RNA polymerase II and post-transcriptionally modified by addition of a 5'-cap and a 3'-poly (A) tail. Subsequently, the pri-miRNA undergoes a number of processing steps in the nucleus and cytoplasm, and ends up as a mature approximately 22 nt miRNA, which can exert its function by binding to the 3'-untranslated region of a subset of mRNAs. Binding of the miRNA to the mRNA results in a reduced translation rate and/or increased degradation of the mRNA. In this way a large number of cellular pathways, such as cellular proliferation, differentiation, and apoptosis, are regulated by mi-RNAs. As corruption of these pathways is the hallmark of many cancers, dysregulation of miRNA biogenesis or expression levels may lead to tumorigenesis. The mechanisms that alter the expression of miRNAs are similar to those that change the expression levels of mRNAs of tumor suppressor- and oncogenes, i.e. gross genomic aberrations, epigenetic changes, and minor mutations affecting the expression level, processing, or target-interaction potential of the miRNA. Furthermore, expression profiling of miRNAs has been found to be useful for classification of different tumor types. Taken together, miRNAs can be classified as onco-miRs or tumor suppressor-miRs, and may turn out to be potential targets for cancer therapy.

Epigenetic changes in cancer

A cancer develops when a cell acquires specific growth advantages through the stepwise accumulation of heritable changes in gene function. Basically, this process is directed by changes in two different classes of genes: Tumor suppressor genes that inhibit cell growth and survival and oncogenes that promote cell growth and survival. Since several alterations are usually required for a cancer to fully develop, the malignant phenotype is determined by the compound status of tumor suppressor genes and oncogenes. Cancer genes may be changed by several mechanisms, which potentially alter the protein encoding nucleotide template, change the copy number of genes, or lead to increased gene transcription. Epigenetic alterations, which, by definition, comprise mitotically and meiotically heritable changes in gene expression that are not caused by changes in the primary DNA sequence, are increasingly being recognized for their roles in carcinogenesis. These epigenetic alterations may involve covalent modifications of amino acid residues in the histones around which the DNA is wrapped, and changes in the methylation status of cytosine bases (C) in the context of CpG dinucleotides within the DNA itself. Methylation of clusters of CpGs called "CpG-islands" in the promoters of genes has been associated with heritable gene silencing. The present review will focus on how disruption of the epigenome can contribute to cancer. In contrast to genetic alterations, gene silencing by epigenetic modifications is potentially reversible. Treatment by agents that inhibit cytosine methylation and histone deacetylation can initiate chromatin decondensation, demethylation and reestablishment of gene transcription. Accordingly, in the clinical setting, DNA methylation and histone modifications are very attractive targets for the development and implementation of new therapeutic approaches. Many clinical trials are ongoing, and epigenetic therapy has recently been approved by the United States Food and Drug Administration (US FDA) for use in the treatment of myelodysplastic syndrome (MDS) and primary cutaneous T-cell lymphoma (CTCL).

Genetic and epigenetic alterations of the reduced folate carrier in untreated diffuse large B-cell lymphoma

The reduced folate carrier (RFC) is a transmembrane protein that mediates cellular uptake of reduced folates and antifolate drugs, including methotrexate (MTX). Acquired alterations of the RFC gene have been associated with resistance to MTX in cancer cell lines and primary osteosarcomas. Here, we examined RFC for mutations and promoter hypermethylation in (i) the inherently MTX-resistant lymphoma cell line (RL); (ii) 30 paired cases of acute lymphoblastic leukemia (ALL) obtained at diagnosis and at relapse after treatment with MTX; and (iii) 25 cases of diffuse large B-cell lymphoma (DLBCL) at diagnosis, none of which had been previously exposed to MTX. Aberrant hypermethylation of the RFC promoter occurred in RL cells and two of the primary DLBCLs. In one additional DLBCL, a single-base substitution in RFC was identified, leading to the introduction of a premature termination codon (c.1396C>T; p.Q466X). A missense mutation affecting the 11th transmembrane domain of RFC (c.1250T>C; p.I417T) was found in one case of ALL at diagnosis. In ALL, RFC promoter hypermethylation was found neither at diagnosis nor at relapse and thus is not a common cause of low levels of RFC expression associated with adverse outcome. In DLBCL, genetic and epigenetic alterations of RFC were detected at diagnosis in the absence of a selective MTX pressure, suggesting that these alterations may possibly contribute to the development of lymphoma.

[Acquired mutations--basic cancer biology]

It is now well-established that cancer is a genetic disease, although in most cases not inherited. A sporadic cancer develops when a somatic cell acquires specific growth advantages through successive accumulation of changes in cancer genes, including oncogenes, tumor suppressor genes and stability genes. Alterations of these genes lead to deregulation of cellular signaling pathways and abnormal growth. Herein, we give a brief overview of the basic genetic changes in cancer and discuss how specific gene alterations may contribute to the development of malignant melanoma.

Microarray-based classification of diffuse large B-cell lymphoma

OBJECTIVE

Hierarchical clusterings of diffuse large B-cell lymphoma (DLBCL) based on gene expression signatures have previously been used to classify DLBCL into Germinal Center B-cell (GCB) and Activated B-cell (ABC) types. To examine if it was feasible to perform a cross-platform validation on the Affymetrix HG-U133A oligonucleotide arrays and improve the classification, we determined the expression profiles of pretreatment, diagnostic samples from 52 primary nodal DLBCL.

METHODS AND RESULTS

First, three previously published gene lists were converted to the HG-U133A probe sets and used for hierarchical clustering. In this way, three subtypes, including the GCB type (n = 20), the ABC type (n = 25) and an intermediate group, Type-3 (n = 5), were distinguished. The CD10 and Bcl-6 expression as well as t(14;18) translocation were prevalent, but not exclusive to the GCB type. By contrast, MUM1 was only expressed in the ABC and in Type-3 samples. The 5-year survival was similar between the groups, but GCB patients showed a better initial response to CHOP or CHOP-like regimens than the remaining patients and tended to have less advanced disease and lower IPI scores. As a next step, an improved set of classifier genes was generated by analysis of 34 patients that were consistently classified as GCB or ABC in the above analyses. Seventy-eight genes were selected and demonstrated on two previously published data sets (Shipp et al. Nat Med 2002;8:68-74 and Houldsworth et al. Blood 2004;103:1862-1868) to exhibit a higher specificity than the original gene lists.

CONCLUSION

We conclude that gene expression profiling with Affymetrix Genechips is efficient to distinguish between GCB and ABC types of DLBCL and that these are likely to represent separate biological entities. The Genechip platform is highly standardised and therefore useful for future prospective investigations to establish the value of gene expression profiling in the clinical management of DLBCL.

Aberrations of the Chk2 tumour suppressor in advanced urinary bladder cancer

Checkpoint kinase 2 (Chk2) is a tumour suppressor and signal transducer in genome integrity checkpoints that coordinate cell-cycle progression with DNA repair or cell death in response to DNA damage. Defects of Chk2 occur in subsets of diverse sporadic malignancies and predispose to several types of hereditary carcinomas. However, the status of Chk2 in tumours of the urinary bladder remains unknown. Here, we report that among 58 advanced (grade T2-T4) human bladder carcinomas, immunohistochemical analysis revealed tumour-specific reduction or lack of Chk2 protein in 6 (10.3%) cases. Genetic analysis of the latter subset showed that a Chk2-negative carcinoma #668 harboured a truncating mutation 1100delC, in one Chk2 allele and loss of the corresponding second allele. The 1100delC mutation was also found in the germ line of this patient. Sequencing of TP53 in tumour #668 identified two missense mutations. Furthermore, the vast majority of the tumours showed 'unscheduled' activatory phosphorylation on Thr68 of Chk2 in the absence of any DNA-damaging treatment. Our results indicate that the otherwise dormant DNA damage signal transducer Chk2 is aberrantly and constitutively activated in invasive urinary bladder carcinomas, and that such likely proapoptotic checkpoint signalling can be disabled by inactivation of Chk2 and/or p53 tumour suppressors in subsets of these tumours.

Randomized controlled azathioprine withdrawal after more than two years treatment in Crohn's disease: increased relapse rate the following year

INTRODUCTION

Azathioprine is effective for maintenance of remission in Crohn's disease, however, duration of efficacy and the dose response relationship has not been fully evaluated.

AIMS

To investigate whether patients kept in remission by azathioprine treatment for >2 years benefit from further treatment, and to explore dose-response relationship.

PATIENTS AND METHODS

In an open 12-month trial, patients with inactive Crohn's disease after >2 years (median 37 months) of azathioprine treatment were randomized to azathioprine withdrawal or continued treatment. Primary end point was relapse defined as: (i) Crohn's disease activity index rise >/= 75, and Crohn's disease activity index >150 or (ii) disease activity requiring intervention.

RESULTS

Of 29 patients, 28 completed the observation period or relapsed. Eleven of 13 patients (85%) continuing azathioprine remained in remission compared with seven of 15 (47%) observed without azathioprine (P = 0.043). In patients who had been treated with azathioprine >1.60 mg/kg/day the difference was even more pronounced, eight of nine (89%) vs. four of 12 (33%) respectively (P = 0.017).

CONCLUSIONS

Patients with Crohn's disease in remission after >2 years of continuous azathioprine treatment will benefit from further continued treatment. Further controlled studies with azathioprine doses <2.0 mg/kg/day are needed.

Genetic and epigenetic alterations of the APC gene in malignant melanoma

High levels of beta-catenin and activating mutations in the beta-catenin gene (CTNNB1) have been demonstrated in malignant melanomas, implicating dysregulated Wnt signalling in the pathogenesis of this malignancy. We systematically examined melanoma cell lines for activating CTNNB1 mutations as well as genetic and epigenetic alterations of the adenomatous polyposis coli gene (APC), another key component of the Wnt signalling transduction pathway. Of 40 cell lines tested, one carried a truncating APC mutation and loss of the corresponding wild-type allele, and one carried a CTNNB1 missense mutation. Hypermethylation of APC promoter 1A was present in five of the cell lines (13%) and in nine of 54 melanoma biopsies (17%). Cells with truncating APC or activating CTNNB1 mutations showed increased transcription from endogenous and ectopic beta-catenin/T-cell factor (Tcf)-responsive target genes, consistent with the known effects of these alterations on beta-catenin stability and Tcf transactivation. In contrast, cell lines with APC promoter 1A hypermethylation did not show increased Wnt signalling, probably due to residual APC activity expressed from promoter 1B. Suppression of APC transcripts in melanoma cells by stable expression of short hairpin RNAs led to a Wnt signalling-independent increase in cell proliferation, but also reduced the invasive growth in collagen type I. Collectively, our data suggest that the tumour-suppressive function of APC in melanocytic cells is dose dependent. We propose that epigenetic silencing of promoter 1A may contribute to the development of malignant melanoma by reducing the expression of APC to a level that promotes cell proliferation without compromising the invasive capacity.

Infrequent somatic Fas mutations but no evidence of Bcl10 mutations or t(11;18) in primary cutaneous MALT-type lymphoma

Genetic alterations that allow tumour cells to evade apoptosis have recently been identified as key features of extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue type (MALT-type lymphoma). The t(11;18), which produces the putative anti-apoptotic fusion protein API2-MALT1, has been identified in a large proportion of extracutaneous MALT-type lymphomas and a smaller fraction of tumours harbour mutations that inactivate the pro-apoptotic functions of Fas and Bcl10. The present study has examined the status of these genes in 19 primary cutaneous B-cell lymphomas (PCBCLs), 12 of which were MALT-type lymphomas according to the WHO classification. None of the 19 PCBCLs carried the t(11;18) and tumour-specific Bcl10 alterations were not identified at the genomic level or at the mRNA level. Somatic Fas mutations causing truncation of the Fas receptor were identified in two MALT-type lymphomas. Both patients with Fas mutant PCBCL exhibited benign conditions of dysregulated lymphoproliferation. One had autoimmune diabetes and rheumatoid arthritis and the other had a 25-year history of recurrent cutaneous pseudo-lymphomas. It is suggested that Fas mutation permits the survival and hence the accumulation of autoreactive B cells. This expansion of autoreactive B cells is analogous to the expansion of B cells chronically stimulated by exogenous antigens in the development of MALT-type lymphoma.

Interobserver variation in interpretation of serial liver biopsies from patients with chronic hepatitis C

Reliable and accurate assessment of liver histopathology in patients with chronic hepatitis C is important for decision regarding treatment and for evaluation of therapy. However, little data on interobserver variation have been published. In this study, five specialist histopathologists evaluated 46 liver biopsies from 20 patients treated with interferon-alpha. Knodell's and Ishak's scoring systems, De Groote's classification and a four level general necro-inflammatory activity score (GNAS) were applied. Besides kappa statistics, slide by slide analysis was performed. We defined an acceptable slide by slide agreement as eight of ten observer pairs agreed on 80% of the slides. The best agreement was seen for Knodell's and Ishak's fibrosis score, De Groote's classification and GNAS (mean weighted kappa (kappa(w)) = 0.49, 0.51, 0.50 and 0.44, respectively). By condensing data from Knodell's and Ishak's scores to presence or absence of cirrhosis and piecemeal necrosis respectively, concordance was substantial concerning cirrhosis (mean kappa = 0.69 and 0.72, respectively) but only moderate concerning piecemeal necrosis (mean kappa = 0.40 and 0.39, respectively). Slide by slide analysis showed the highest agreement on Knodell's fibrosis score and GNAS; only one point of difference in score was to be accepted to obtain 'eight of ten' agreement. In contrast, five points of difference were necessary to accept in order to reach the same agreement for Knodell's total activity score. Moreover, in serial biopsies the GNAS was sufficient to detect changes in disease activity following treatment. Thus, a simple scoring system with four category scales was reproducible and sufficient for detection of therapy induced changes.

ATM mutations are associated with inactivation of the ARF-TP53 tumor suppressor pathway in diffuse large B-cell lymphoma

The ATM serine-threonine kinase plays a central role in the cellular response to DNA damage. Germ-line mutations in the ATM gene cause ataxia-telangiectasia (A-T), a multisystem disorder associated with predisposition to lymphoma and acute leukemia. Moreover, somatic ATM mutations have been identified in T-cell prolymphocytic leukemia, mantle cell lymphoma, and B-cell chronic lymphocytic leukemia. In this study, the entire ATM coding sequence was examined in genomic DNA from 120 lymphoid neoplasms. Novel mutations and mutations implicated in cancer and/or A-T were found in 9 of 45 diffuse large B-cell lymphomas (DLBCLs), 2 of 24 follicular lymphomas, and 1 of 27 adult acute lymphoblastic leukemias, whereas no such mutations were detected among 24 peripheral T-cell lymphomas. The mutational spectrum consisted of 2 nonsense mutations, 1 mutation affecting RNA splicing, and 10 missense variants. Most of these mutations were associated with loss or mutation of the paired ATM allele, consistent with biallelic inactivation of ATM. Of the 9 DLBCLs with ATM mutations, 7 also carried TP53 mutations and/or deletions of the INK4a/ARF locus (P =.003). The ATM 735C>T substitution previously considered a rare normal variant was found to be 5.6 times more frequent in individuals with DLBCL than in random individuals (P =.026), suggesting that it may predispose to B-cell lymphoma. Our data suggest that ATM mutations contribute to the development of DLBCL, and that ATM and the ARF-p53 tumor suppressor pathway may cooperate in the pathogenesis of this malignancy.

Interferon alfa-2b alone or combined with recombinant granulocyte-macrophage colony-stimulating factor as treatment of chronic hepatitis C

BACKGROUND

To compare the effect of combination therapy with interferon-alpha (INF-alpha) and granulocyte-macrophage colony-stimulating factor (GM-CSF) to monotherapy with INF-alpha in patients with chronic hepatitis C infection.

METHODS

Forty-five consecutive patients with chronic hepatitis C, all presenting with elevated serum alanine aminotransferases and viremia, were randomized to receive either 1) INF-alpha + GM-CSF for 3 months followed by INF-alpha alone for 9 months (n = 23) or 2) INF-alpha for 12 months (n = 22). Both drugs were administered 3 times weekly in doses of 3 mU (INF-alpha) and 50-100 microg depending on body weight (GM-CSF).

RESULTS

At baseline, there was no difference between the treatment groups in terms of age, sex, ALT level, viral load, genotype or histological activity and fibrosis in a pretreatment liver biopsy. After 12 months' treatment, more patients treated with GM-CSF+ INF-alpha compared to patients receiving monotherapy had normalized ALT, 65% and 32%, respectively (P = 0.03), but there was no difference in percentages of patients with viral clearance between the 2 groups, 48% and 32%, respectively (P = 0.27). At 6 months' follow-up, the biochemical response had declined to 35% in the combination therapy group and to 23% in the monotherapy group (P = 0.37); viral clearance had declined to 22% and 27%, respectively (P = 0.67), and the overall sustained response rate was 22% and 23%, respectively (P = 1.00).

CONCLUSIONS

Even though patients receiving INF-alpha + GM-CSF had a significant better biochemical response during treatment compared to patients receiving monotherapy, the sustained biochemical and virological response was not increased. Thus, GM-CSF hardly plays any role in the future treatment of chronic hepatitis C.

Profiling DNA methylation by melting analysis

The idea of modifying DNA with bisulfite has paved the way for a variety of polymerase chain reaction (PCR) methods for accurately mapping 5-methylcytosine at specific genes. Bisulfite selectively deaminates cytosine to uracil under conditions where 5-methylcytosine remains unreacted. Following conventional PCR amplification of bisulfite-treated DNA, original cytosines appear as thymine while 5-methylcytosines appear as cytosine. Because the relative thermostability of a DNA duplex increases with increasing content of G:C base pairs, PCR products originating from DNA templates with different contents of 5-methylcytosine differ in melting temperature, i.e., the temperature required to convert the double helix into random coils. We describe two methods that resolve differentially methylated DNA sequences on the basis of differences in melting temperature. The first method integrates PCR amplification of bisulfite-treated DNA and subsequent melting analysis by using a thermal cycler coupled with a fluorometer. By including in the reaction a PCR-compatible, fluorescent dye that specifically binds to double-stranded DNA, the melting properties of the PCR product can be examined directly in the PCR tube by continuous fluorescence monitoring during a temperature transition. The second method relies on resolution of alleles with different 5-methylcytosine contents by analysis of PCR products in a polyacrylamide gel containing a gradient of chemical denaturants. Optimal resolution of differences in melting temperature is achieved by a special design of PCR primers. Both methods allow resolution of "heterogeneous" methylation, i.e., the situation where the content and distribution of 5-methylcytosine in a target gene differ between different molecules in the same sample.

A case of lymphoblastoid natural killer (NK)-cell lymphoma: association with the NK-cell receptor complex CD94/NKG2 and TP53 intragenic deletion

The clinical, histological, phenotypic and genotypic features of a lymphoblastoid natural killer (NK)-cell lymphoma presenting in the skin in a young caucasian woman are described. The disease behaved aggressively, but long-lasting remission was obtained by combination chemotherapy followed by autologous bone marrow transplantation. The blastoid cells were positive for terminal deoxynucleotidyl transferase, CD34, CD56 and CD4. Furthermore, the NK-cell receptor complex CD94/NKG2 was strongly expressed, as shown by examination with reverse transcription-polymerase chain reaction. The T-cell receptor (TCR)-gamma genes were in germline, and with the exception of CD4 all T-cell antigens were negative, including CD3, TCR-beta, TCR-delta, TIA-1, granzyme B and perforin. Epstein-Barr virus was negative, and no expression was seen of myeloid cell-associated markers. Molecular analysis showed no abnormalities of the CDKN2A (p16), CDKN2B (p15) or TNFRSF6 (Fas) genes. By contrast, a 34-bp deletion in exon 7 of the TP53 (p53) gene was detected. It is suggested that lymphoblastoid NK-cell lymphoma, which is a rare but distinctive disease, originates from NK cell precursors and may be associated with and possibly caused by alterations in the TP53 gene. Experience is too limited to warrant therapeutic suggestions. However, stem cell transplantation may be a useful option in younger patients.