EGR2 mutations define a new clinically aggressive subgroup of chronic lymphocytic leukemia

Recurrent mutations within EGR2 were recently reported in advanced-stage chronic lymphocytic leukemia (CLL) patients and associated with a worse outcome. To study their prognostic impact, 2403 CLL patients were examined for mutations in the EGR2 hotspot region including a screening (n=1283) and two validation cohorts (UK CLL4 trial patients, n=366; CLL Research Consortium (CRC) patients, n=490). Targeted deep-sequencing of 27 known/postulated CLL driver genes was also performed in 38 EGR2-mutated patients to assess concurrent mutations. EGR2 mutations were detected in 91/2403 (3.8%) investigated cases, and associated with younger age at diagnosis, advanced clinical stage, high CD38 expression and unmutated IGHV genes. EGR2-mutated patients frequently carried ATM lesions (42%), TP53 aberrations (18%) and NOTCH1/FBXW7 mutations (16%). EGR2 mutations independently predicted shorter time-to-first-treatment (TTFT) and overall survival (OS) in the screening cohort; they were confirmed associated with reduced TTFT and OS in the CRC cohort and independently predicted short OS from randomization in the UK CLL4 cohort. A particularly dismal outcome was observed among EGR2-mutated patients who also carried TP53 aberrations. In summary, EGR2 mutations were independently associated with an unfavorable prognosis, comparable to CLL patients carrying TP53 aberrations, suggesting that EGR2-mutated patients represent a new patient subgroup with very poor outcome.

Inactivation of the putative ubiquitin-E3 ligase PDLIM2 in classical Hodgkin and anaplastic large cell lymphoma

Apart from its unique histopathological appearance with rare tumor cells embedded in an inflammatory background of bystander cells, classical Hodgkin lymphoma (cHL) is characterized by an unusual activation of a broad range of signaling pathways involved in cellular activation. This includes constitutive high-level activity of nuclear factor-κB (NF-κB), Janus kinase/signal transducer and activator of transcription (JAK/STAT), activator protein-1 (AP-1) and interferon regulatory factor (IRF) transcription factors (TFs) that are physiologically only transiently activated. Here, we demonstrate that inactivation of the putative ubiquitin E3-ligase PDLIM2 contributes to this TF activation. PDLIM2 expression is lost at the mRNA and protein levels in the majority of cHL cell lines and Hodgkin and Reed–Sternberg (HRS) cells of nearly all cHL primary samples. This loss is associated with PDLIM2 genomic alterations, promoter methylation and altered splicing. Reconstitution of PDLIM2 in HRS cell lines inhibits proliferation, blocks NF-κB transcriptional activity and contributes to cHL-specific gene expression. In non-Hodgkin B-cell lines, small interfering RNA-mediated PDLIM2 knockdown results in superactivation of TFs NF-κB and AP-1 following phorbol 12-myristate 13-acetate (PMA) stimulation. Furthermore, expression of PDLIM2 is lost in anaplastic large cell lymphoma (ALCL) that shares key biological aspects with cHL. We conclude that inactivation of PDLIM2 is a recurrent finding in cHL and ALCL, promotes activation of inflammatory signaling pathways and thereby contributes to their pathogenesis.

Long-term follow-up of fertility and pregnancy in autoimmune diseases after autologous haematopoietic stem cell transplantation

Issues of fertility and pregnancy require special attention in the long-term care of patients with autoimmune diseases (AD), who are candidates for haematopoietic stem cell transplantation (HSCT). In this single-centre observational study, we report fertility status and pregnancy outcomes in 15 patients (11 female and 4 male) after immunoablation with cyclophosphamide, antithymocyte globulin and autologous CD34⁺-selected HSCT for severe, refractory AD. The median follow-up after HSCT was 12 years (range 2-16 years). Impaired fertility was observed in six patients (five females and one male) before HSCT based on sexual hormone measurements. Higher age and cumulative cyclophosphamide dosage before HSCT correlated with fertility impairment. Median serum level of follicle-stimulating hormone (FSH) was significantly higher in female patients at 1 year after HSCT compared to baseline values, but premature ovarian failure developed in only one patient. Four women had five pregnancies and six healthy offsprings during follow-up, and no miscarriages were observed. The mothers were in treatment-free remissions during conception. No peripartal flare of their AD occurred. Although AD patients undergoing HSCT are at risk of developing infertility, pre-HSCT treatment and patients' age seem to have higher impact on long-term fertility status than HSCT itself. HSCT offers the opportunity to conceive during treatment-free remissions with favourable pregnancy outcomes.

Frequent induction of chromosomal aberrations in in vivo skin fibroblasts after allogeneic stem cell transplantation: hints to chromosomal instability after irradiation

Background

Total body irradiation (TBI) has been part of standard conditioning regimens before allogeneic stem cell transplantation for many years. Its effect on normal tissue in these patients has not been studied extensively.

Method

We studied the in vivo cytogenetic effects of TBI and high-dose chemotherapy on skin fibroblasts from 35 allogeneic stem cell transplantation (SCT) patients. Biopsies were obtained prospectively (n = 18 patients) before, 3 and 12 months after allogeneic SCT and retrospectively (n = 17 patients) 23–65 months after SCT for G-banded chromosome analysis.

Results

Chromosomal aberrations were detected in 2/18 patients (11 %) before allogeneic SCT, in 12/13 patients (92 %) after 3 months, in all patients after 12 months and in all patients in the retrospective group after allogeneic SCT. The percentage of aberrant cells was significantly higher at all times after allogeneic SCT compared to baseline analysis. Reciprocal translocations were the most common aberrations, but all other types of stable, structural chromosomal aberrations were also observed. Clonal aberrations were observed, but only in three cases they were detected in independently cultured flasks. A tendency to non-random clustering throughout the genome was observed. The percentage of aberrant cells was not different between patients with and without secondary malignancies in this study group.

Conclusion

High-dose chemotherapy and TBI leads to severe chromosomal damage in skin fibroblasts of patients after SCT. Our long-term data suggest that this damage increases with time, possibly due to in vivo radiation-induced chromosomal instability.

Anti-CD22 and anti-CD79B antibody drug conjugates are active in different molecular diffuse large B-cell lymphoma subtypes

Antibody drug conjugates (ADCs), in which cytotoxic drugs are linked to antibodies targeting antigens on tumor cells, represent promising novel agents for the treatment of malignant lymphomas. Pinatuzumab vedotin is an anti-CD22 ADC and polatuzumab vedotin an anti-CD79B ADC that are both linked to the microtubule-disrupting agent monomethyl auristatin E (MMAE). In the present study, we analyzed the activity of these agents in different molecular subtypes of diffuse large B-cell lymphoma (DLBCL) both in vitro and in early clinical trials. Both anti-CD22-MMAE and anti-CD79B-MMAE were highly active and induced cell death in the vast majority of activated B-cell-like (ABC) and germinal center B-cell-like (GCB) DLBCL cell lines. Similarly, both agents induced cytotoxicity in models with and without mutations in the signaling molecule CD79B. In line with these observations, relapsed and refractory DLBCL patients of both subtypes responded to these agents. Importantly, a strong correlation between CD22 and CD79B expression in vitro and in vivo was not detectable, indicating that patients should not be excluded from anti-CD22-MMAE or anti-CD79B-MMAE treatment because of low target expression. In summary, these studies suggest that pinatuzumab vedotin and polatuzumab vedotin are active agents for the treatment of patients with different subtypes of DLBCL.

Transformation and additional malignancies are leading risk factors for an adverse course of disease in marginal zone lymphoma

BACKGROUND

Marginal zone lymphoma (MZL) is a non-Hodgkin lymphoma that occurs as extra nodal, nodal, or splenic. While MZL is generally considered an indolent disease, a substantial percentage of patients follow an unfavorable course. The objective of this retrospective analysis was to identify predictors for a reduced overall survival (OS), or conversely an increased OS.

PATIENTS AND METHODS

One hundred and ninety-seven MZL patients were analyzed. Apart from assessing previously published risk factors, concomitant morbidity at diagnosis, transformation into aggressive lymphoma, and occurrence of additional malignancies were evaluated.

RESULTS

Next to the known risk factors, i.e. above 60 years of age and elevated serum lactate dehydrogenase (LDH), we demonstrate that transformation into aggressive lymphoma, as well as additional malignancies, are important independent risk factors for a shortened OS in a multivariate analysis, irrespective of the MZL localization. Impressively, in the group of patients lacking LDH elevation, transformation, and/or additional malignancies, only 1 of 63 patients died during follow-up compared with 37 of 87 patients in the high-risk group (HR = 22.8; 95% confidence interval 3.1-167.0; P = 0.002).

CONCLUSIONS

Our analysis proposes novel risk factors and warrants for a continuous follow-up to detect the occurrence of transformation and additional malignancies early on.

Notch pathway inhibition controls myeloma bone disease in the murine MOPC315.BM model

Despite evidence that deregulated Notch signalling is a master regulator of multiple myeloma (MM) pathogenesis, its contribution to myeloma bone disease remains to be resolved. Notch promotes survival of human MM cells and triggers human osteoclast activity in vitro. Here, we show that inhibition of Notch through the γ-secretase inhibitor XII (GSI XII) induces apoptosis of murine MOPC315.BM myeloma cells with high Notch activity. GSI XII impairs murine osteoclast differentiation of receptor activator of NF-κB ligand (RANKL)-stimulated RAW264.7 cells in vitro. In the murine MOPC315.BM myeloma model GSI XII has potent anti-MM activity and reduces osteolytic lesions as evidenced by diminished myeloma-specific monoclonal immunoglobulin (Ig)-A serum levels and quantitative assessment of bone structure changes via high-resolution microcomputed tomography scans. Thus, we suggest that Notch inhibition through GSI XII controls myeloma bone disease mainly by targeting Notch in MM cells and possibly in osteoclasts in their microenvironment. We conclude that Notch inhibition is a valid therapeutic strategy in MM.

SPARC expression in resected pancreatic cancer patients treated with gemcitabine: results from the CONKO-001 study

BACKGROUND

Previous investigations in pancreatic cancer suggested a prognostic role for secreted protein acidic and rich in cysteine (SPARC) expression in the peritumoral stroma but not for cytoplasmic SPARC expression. The aim of this study was to evaluate the impact of SPARC expression in pancreatic cancer patients treated with gemcitabine compared with untreated patients.

PATIENTS AND METHODS

CONKO-001 was a prospective randomized phase III study investigating the role of adjuvant gemcitabine when compared with observation. Tissue samples of 160 patients were available for SPARC immunohistochemistry on tissue microarrays to evaluate its impact on patient outcome.

RESULTS

Strong stromal SPARC expression was associated with worse disease-free survival (DFS) and overall survival (OS) in the overall study population (DFS: P = 0.005, OS: P = 0.033). Its negative prognostic impact was restricted to patients treated with gemcitabine (DFS: P = 0.007, OS: P = 0.006). High cytoplasmic SPARC expression also was associated with worse patient outcome (DFS: P = 0.041, OS: P = 0.011). Again the effect was restricted to patients treated with gemcitabine (DFS: P = 0.002, OS: P = 0.003). In multivariable analysis, SPARC expression was independently predictive of patient outcome.

CONCLUSIONS

Our data confirm the prognostic significance of SPARC expression after curatively intended resection. The negative prognostic impact was restricted to patients who received adjuvant treatment with gemcitabine, suggesting SPARC as a predictive marker for response to gemcitabine.

An individual patient-data comparison of combined modality therapy and ABVD alone for patients with limited-stage Hodgkin lymphoma

BACKGROUND

Treatment options for patients with nonbulky stage IA-IIA Hodgkin lymphoma include combined modality therapy (CMT) using doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD) plus involved-field radiation therapy (IFRT), and chemotherapy with ABVD alone. There are no mature randomized data comparing ABVD with CMT using modern radiation techniques.

PATIENTS AND METHODS

Using German Hodgkin Study Group HD10/HD11 and NCIC Clinical Trials Group HD.6 databases, we identified 588 patients who met mutually inclusive eligibility criteria from the preferred arms of HD10 or 11 (n = 406) and HD.6 (n = 182). We evaluated time to progression (TTP), progression-free (PFS) and overall survival, including in three predefined exploratory subset analyses.

RESULTS

With median follow-up of 91 (HD10/11) and 134 (HD.6) months, respective 8-year outcomes were for TTP, 93% versus 87% [hazard ratio (HR) 0.44, 95% confidence interval (CI) 0.24-0.78]; for PFS, 89% versus 86% (HR 0.71, 95% CI 0.42-1.18) and for overall survival, 95% versus 95% (HR 1.09, 95% CI 0.49-2.40). In the exploratory subset analysis including HD10 eligible patients who achieved complete response (CR) or unconfirmed complete response (CRu) after two cycles of ABVD, 8-year PFS was 87% (HD10) versus 95% (HD.6) (HR 2.8; 95% CI 0.64-12.5) and overall survival 96% versus 100%. In contrast, among those without CR/CRu after two cycles of ABVD, 8-year PFS was 88% versus 74% (HR 0.35; 95% CI 0.16-0.79) and overall survival 95% versus 91%, respectively (HR 0.42; 95% CI 0.12-1.44).

CONCLUSIONS

In patients with nonbulky stage IA-IIA Hodgkin lymphoma, CMT provides better disease control than ABVD alone, especially among those not achieving complete response after two cycles of ABVD. Within the follow-up duration evaluated, overall survivals were similar. Longer follow-up is required to understand the implications of radiation and chemotherapy-related late effects.

CLINICAL TRIALS

The trials included in this analysis were registered at ClinicalTrials.gov: HD10 - NCT00265018, HD11 - NCT00264953, HD.6 - NCT00002561.

Blood group determinates incidence for pancreatic cancer in Germany

Background: Genetic risk factors for sporadic pancreatic cancer are largely unknown but actually under high exposure. Findings of correlations between the AB0 blood group system (Chromosome 9q34,1—q34,2) and the risk of pancreatic cancer (PC) in patients from Asia, America and south Europe have already been published. So far it is unclear, whether this correlation between blood group an PC incidence can be found in German patients as well.

Methods: One hundred and sixty-six patients who underwent a resection of PC were evaluated in a period between 2000 and 2010. Blood group reference distribution for the German population is given as: 0: 41%; A: 43%; B: 11%; AB: 5%; Rhesus positive: 85%; Rhesus negative: 15%. Analyses were done using the non-parametric Chi²-test (p-value two sided; SPSS 19.0).

Results: Median age was 62 (34–82) years. Gender: female 73/44%; male: 93/56%. Observed blood group proportions: 0: 43 (25.9%)/A: 94 (56.6%)/B: 16 (9.6%)/AB: 13 (7.8%)/Rhesus positive: 131 (78.9%)/negative: 35 (21.1%). We detected a significant difference to the German reference distribution of the AB0 system (Chi² 19.34, df 3, p < 0.001). Rhesus factor has no impact on AB0-distribution (Chi² 4.13, df 3, p = 0.25), but differs significantly from reference distribution—probably due to initial AB0-variation (Chi² 4.82, df 1, p = 0.028). The odds ratio for blood group A is 2.01 and for blood group 0 is 0.5.

Conclusions: The incidence of PC in the German cohort is highly associated with the AB0-system as well. More patients with blood group A suffer from PC (p < 0.001) whereas blood group 0 was less frequent in patients with PC (p < 0.001). Thus, our findings support the results from other non-German surveys. The causal trigger points of this carcinogenesis correlation are still not known.

The tumour suppressor p53 is frequently nonfunctional in Sézary syndrome

BACKGROUND

Primary cutaneous T-cell lymphomas (CTCLs) are a heterogeneous group with Sézary syndrome (SS) as one of the most aggressive variants. Recently, we identified a loss of E2A as a recurrent event in SS, which enhanced proliferation via upregulation of the proto-oncogene MYC. MYC-induced transformation usually requires deleterious alterations of key apoptotic genes including p53; however, p53 functionality and mutation status in SS are unclear.

OBJECTIVES

We investigated functionality of p53 signalling by pharmacological treatment with the MDM2 antagonist nutlin-3, which might result in p53 activation. Furthermore, we analysed the TP53 mutation status in CTCL cell lines and highly purified tumour cells from patients with SS by mRNA and DNA sequencing.

METHODS

We analysed the apoptosis induction due to nutlin-3 treatment in various SS cell lines and primary patient samples by annexin V/propidium iodide staining. Induction of p53 target genes was analysed by immunoblotting, and TP53 was sequenced at the mRNA and DNA level.

RESULTS

We identified various TP53 mutations and an impaired p53 signalling in the vast majority of the investigated cell lines and primary SS cells.

CONCLUSIONS

In accordance with the importance of MYC deregulation in SS, p53 signalling is frequently nonfunctional in SS. However, although most likely ineffective as exclusive treatment in SS, it remains possible that pharmacological p53 activation could be beneficial in combination with other approaches including classical chemotherapeutics.

CCL21 (SLC) improves tumor protection by a DNA vaccine in a Her2/neu mouse tumor model

Secondary lymphoid-tissue chemokine (SLC/CCL21) is a CC chemokine that is constitutively expressed in various lymphoid tissues and binds to chemokine receptor CCR7 on mature dendritic cells (DCs) and distinct T-and B-cell sub-populations. In vivo, CCL21 regulates the encounters between DC and T cells and thus is a key regulator of adaptive immune responses. We asked whether CCL21 is able to augment immunogenicity of a DNA-based vaccine against Her2/neu in a Balb/c mouse model with syngeneic Her2/neu+ tumor cells (D2F2/E2). Mice were vaccinated intramuscularly with plasmid DNA (pDNA) on day 1 and boosted on day 15; tumor challenge was performed subcutaneously on day 25. Coexpression of CCL21 and Her-2/neu resulted in induction of a TH1-polarized immune response and substantial improvement of the protective effect of the DNA vaccine. Coexpression of tumor antigen pDNA(Her2/neu) with both pDNA(GM-CSF) and pDNA(CCL21) as adjuvants led to further improvement of protection by the vaccine (70% tumor-free mice on day 35 vs 40% with either adjuvant alone vs 5-10% with tumor antigen alone). Our results show that CCL21 is a potent adjuvant for DNA vaccination, particularly in combination with granulocyte-macrophage colony-stimulating factor (GM-CSF). Clinical use of a pDNA(Her2/neu/CCL21/GM-CSF) vaccine might be particularly promising in minimal residual Her2/neu+ breast cancer.

Reduced-intensity conditioning using fludarabine and antithymocyte globulin alone allows stable engraftment in a patient with dyskeratosis congenita

Dyskeratosis congenita (DC) is a rare inherited disorder characterized by the triad of nail dystrophy, mucosal leukoplakia, and reticular pigmentation. Bone marrow failure is the principal cause of early mortality, and stem cell transplantation is the only cure for these patients. However, the results of conventional hematopoietic stem cell transplantation (HSCT) for patients with DC are poor because of the high incidence of transplant-related complications. We describe the successful treatment of a 21-year-old male with DC by nonmyeloablative HSCT from a matched unrelated donor. The gene responsible for the X-linked form of DC was screened and hemizygosity for the mutation Gln31Lys was found, which is consistent with the diagnosis. The conditioning regimen consisted of only fludarabine and antithymocyte globulin. Additionally, a graft-versus-host disease (GVHD) prophylaxis was administered with cyclosporine A (CSA) and mycophenolate mofetil (MMF). The regimen was well tolerated, no severe posttransplantation complications were observed, and engraftment was rapid and complete (granulocytes on day +11 and platelets on day +13). Seven months after HSCT, the patient developed GVHD of the liver after tapering CSA which was successfully treated with prednisolone, CSA, and MMF. At the time of reporting, 3 years after HSCT, the patient remained in good clinical condition with minimal signs of chronic GVHD of the oral mucosa. Thus, we conclude that a low-intensity conditioning regimen might be sufficient to induce permanent engraftment by using matched unrelated donor HSCT in DC patients and may avoid severe organ toxicity. Although allogeneic HSCT in patients with DC will not cure the underlying genetic defect it may significantly prolong survival through effective therapy for hematologic complications.

Cellular senescence predicts treatment outcome in metastasised colorectal cancer

BACKGROUND

Cellular senescence is a terminal cell-cycle arrest that occurs in response to activated oncogenes and DNA-damaging chemotherapy. Whether cancer cell senescence at diagnosis might be predictive for treatment outcome is unknown.

METHODS

A senescence index (SI) was developed and used to retrospectively correlate the treatment outcome of 30 UICC stage IV colorectal cancer (CRC) patients with their SI at diagnosis.

RESULTS

5-Fluorouracil/leucovorin-treated CRC patients achieved a significantly longer progression-free survival when presenting with SI-positive tumours before therapy (median 12.0 vs 6.0 months; P=0.044).

CONCLUSION

Cancer cell senescence predicts treatment outcome in metastasised CRC. Prospective analyses of larger patient cohorts are needed.