[Show abstract][Hide abstract] ABSTRACT: Aim of this prospective study was to investigate prognostic significance of increased bone marrow microcirculation as detected by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for survival and local complications in patients with multiple myeloma (MM).
We performed DCE-MRI of the lumbar spine in 131 patients with newly diagnosed MM and analysed data according to the Brix model to acquire amplitude A and exchange rate constant k ep. In 61 patients a second MRI performed after therapy was evaluated to assess changes in vertebral height and identify vertebral fractures.
Correlation analysis revealed significant positive association between beta2-microglobulin as well as immunoparesis with DCE-MRI parameters A and k ep. Additionally, A was negatively correlated with haemoglobin levels and k ep was positively correlated with LDH levels. Higher baseline k ep values were associated with decreased vertebral height in a second MRI (P = 0.007) and A values were associated with new vertebral fractures in the lower lumbar spine (P = 0.03 for L4). Pre-existing lytic bone lesions or remission after therapy had no impact on the occurrence of vertebral fractures. Multivariate analysis revealed that amplitude A is an independent adverse risk factor for overall survival.
DCE-MRI is a non-invasive tool with significance for systemic prognosis and vertebral complications.
• Qualitative parameters from DCE-MRI are correlated with established factors of disease activity • Increased marrow microcirculation might be a risk factor for loss of vertebral height and fractures • Amplitude A is an independent predictor for shortened overall survival.
European Radiology 07/2015; DOI:10.1007/s00330-015-3928-4 · 4.34 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to determine the minimal set of genetic alterations required for the development of a very low risk clinically symptomatic gastro-intestinal stromal tumour within the stomach wall. We studied the genome of a very low-risk gastric gastro-intestinal stromal tumour by whole-genome sequencing, comparative genomic hybridisation and methylation profiling. The studied tumour harboured two typical genomic lesions: loss of the long arm of chromosome 14 and an activating mutation in exon 11 of KIT. Besides these genetic lesions, only two point mutations that may affect tumour progression were identified: A frame-shift deletion in RNF146 and a missense mutation in a zinc finger of ZNF407. Whilst the frameshift deletion in RNF146 seemed to be restricted to this particular tumour, a similar yet germline mutation in ZNF407 was found in a panel of 52 gastro-intestinal stromal tumours from different anatomical sites and different categories. Germline polymorphisms in the mitotic checkpoint proteins Aurora kinase A and BUB1 kinase B may have furthered tumour growth. The epigenetic profile of the tumour matches that of other KIT-mutant tumours. We have identified mutations in three genes and loss of the long arm of chromosome 14 as the so far minimal set of genetic abnormalities sufficient for the development of a very low risk clinically symptomatic gastric stromal tumour.
PLoS ONE 06/2015; 10(6):e0130149. DOI:10.1371/journal.pone.0130149 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We report on a series of sequential events leading to long-term survival and cure of pediatric X-linked chronic granulomatous disease (X-CGD) patients after gamma-retroviral gene therapy (GT) and rescue HSCT. Due to therapy-refractory life-threatening infections requiring hematopoietic stem cell transplantation (HSCT) but absence of HLA-identical donors, we treated 2 boys with X-CGD by GT. Following GT both children completely resolved invasive Aspergillus nidulans infections. However, one child developed dual insertional activation of ecotropic viral integration site 1 (EVI1) and signal transducer and activator of transcription 3 (STAT3) genes, leading to myelodysplastic syndrome (MDS) with monosomy 7. Despite resistance to mismatched allo-HSCT with standard myeloablative conditioning, secondary intensified rescue allo-HSCT resulted in 100% donor chimerism and disappearance of MDS. The other child did not develop MDS despite expansion of a clone with a single insertion in the myelodysplasia syndrome 1 (MDS1) gene and was cured by early standard allo-HSCT. The slowly developing dominance of clones harboring integrations in MDS1-EVI1 may guide clinical intervention strategies, i.e. early rescue allo-HSCT, prior to malignant transformation. GT was essential for both children to survive and to clear therapy-refractory infections, and future GT with safer lentiviral self-inactivated (SIN) vectors may offer a therapeutic alternative for X-CGD patients suffering from life-threatening infections and lacking HLA-identical HSC donors.
Current Gene Therapy 05/2015; 15(4). DOI:10.2174/1566523215666150515145255 · 4.91 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Mutations of the tumor suppressor p53 lead to chemotherapy resistance and a dismal prognosis in chronic lymphocytic leukemia (CLL). While p53 targets are used to identify patient subgroups with impaired p53 function, a comprehensive assessment of non-coding RNA targets of p53 in CLL is missing. We exploited the impaired transcriptional activity of mutant p53 to map out p53 targets in CLL by small RNA sequencing. We describe the landscape of p53-dependent miRNA/non-coding RNA induced in response to DNA damage in CLL. Besides the key p53 target miR-34a, we identify a set of p53-dependent miRNAs (miR-182-5p, miR-7-5p, miR-320c/d). In addition to miRNAs, the long non-coding RNAs (lncRNAs) NEAT1 and lincRNA-p21 are induced in response to DNA damage in the presence of functional p53 but not in CLL with p53 mutation. Induction of NEAT1 and lincRNA-p21 closely correlated to the induction of cell death after DNA damage. We used isogenic lymphoma cell line models to prove p53 dependence of NEAT1 and lincRNA-p21. The current work describes the p53-dependent miRNome and identifies lncRNAs NEAT1 and lincRNA-p21 as novel elements of the p53-dependent DNA damage response machinery in CLL and lymphoma.Leukemia accepted article preview online, 14 May 2015. doi:10.1038/leu.2015.119.
Leukemia: official journal of the Leukemia Society of America, Leukemia Research Fund, U.K 05/2015; DOI:10.1038/leu.2015.119 · 9.38 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We aimed at demonstrating non-inferiority of bortezomib/cyclophosphamide/dexamethasone (VCD) compared to bortezomib/doxorubicin/dexamethasone (PAd) induction therapy with respect to very good partial response rates or better (≥VGPR) in 504 newly diagnosed, transplant-eligible multiple myeloma (MM) patients. VCD was found to be non-inferior to PAd with respect to ≥VGPR rates (37.0% vs. 34.3%, p=0.001). The rates of progressive disease (PD) were 0.4% (VCD) vs. 4.8% (PAd) (p=0.003). In the PAd arm, 11 of 12 patients with PD had either renal impairment (creatinine ≥2 mg/dl) at diagnosis or the cytogenetic abnormality gain 1q21, whereas no PD was observed in these subgroups in the VCD arm. Leucocytopenia/neutropenia (≥3°) occurred more frequently in the VCD arm (35.2% vs. 11.3%, p<0.001). Neuropathy rates (≥2°) were higher in the PAd group (14.9% vs. 8.4%, p=0.03). Serious Adverse Events (SAEs), both overall and those related to thromboembolic events, were higher in the PAd group (32.7% vs. 24.0%, p=0.04 and 2.8% vs. 0.4%, p=0.04). Stem cell collection was not impeded by VCD. VCD is as effective as PAd in terms of achieving ≥VGPR rates with fewer PD and has a favorable toxicity profile. Therefore, VCD is preferable to PAd as induction therapy.Leukemia accepted article preview online, 19 March 2015. doi:10.1038/leu.2015.80.
Leukemia: official journal of the Leukemia Society of America, Leukemia Research Fund, U.K 03/2015; 29(8). DOI:10.1038/leu.2015.80 · 9.38 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Haematopoietic stem cells (HSCs) are responsible for the lifelong production of blood cells. The accumulation of DNA damage in HSCs is a hallmark of ageing and is probably a major contributing factor in age-related tissue degeneration and malignant transformation. A number of accelerated ageing syndromes are associated with defective DNA repair and genomic instability, including the most common inherited bone marrow failure syndrome, Fanconi anaemia. However, the physiological source of DNA damage in HSCs from both normal and diseased individuals remains unclear. Here we show in mice that DNA damage is a direct consequence of inducing HSCs to exit their homeostatic quiescent state in response to conditions that model physiological stress, such as infection or chronic blood loss. Repeated activation of HSCs out of their dormant state provoked the attrition of normal HSCs and, in the case of mice with a non-functional Fanconi anaemia DNA repair pathway, led to a complete collapse of the haematopoietic system, which phenocopied the highly penetrant bone marrow failure seen in Fanconi anaemia patients. Our findings establish a novel link between physiological stress and DNA damage in normal HSCs and provide a mechanistic explanation for the universal accumulation of DNA damage in HSCs during ageing and the accelerated failure of the haematopoietic system in Fanconi anaemia patients.
[Show abstract][Hide abstract] ABSTRACT: In order to understand the precise disease driving mechanisms in acute myeloid leukemia (AML), comparison of patient matched hematopoietic stem cells (HSC) and leukemia stem cells (LSC) is essential. In this analysis we have examined the value of aldehyde dehydrogenase (ALDH) activity in combination with CD34 expression for the separation of HSC from LSC in 104 patients with de novo AML. The majority of AML patients (80 out of 104) had low percentages of cells with high ALDH activity (ALDH+ cells) (<1.9%; ALDH-rare AML), whereas 24 patients had relatively numerous ALDH+ cells (≥1.9%; ALDH-numerous AML). In patients with ALDH-rare AML, normal HSC could be separated by their CD34+ALDH+ phenotype, whereas LSC were exclusively detected among CD34+ALDH- cells. For patients with ALDH-numerous AML, the CD34+ALDH+ subset consisted mainly of LSC and separation from HSC was not feasible. Functional analyses further showed that ALDH+ cells from ALDH-numerous AML were quiescent, refractory to ARA-C treatment and capable of leukemic engraftment in a xenogenic mouse transplantation model. Clinically, resistance to chemotherapy and poor long-term outcome were also characteristic for patients with ALDH-numerous AML providing an additional risk-stratification tool. The difference in spectrum and relevance of ALDH activity in the putative LSC populations demonstrates, in addition to phenotypic and genetic, also functional heterogeneity of leukemic cells and suggests divergent roles for ALDH activity in normal HSC versus LSC. By acknowledging these differences our study provides a new and useful tool for prospective identification of AML cases in which separation of HSC from LSC is possible. This article is protected by copyright. All rights reserved.
International Journal of Cancer 12/2014; 137(3). DOI:10.1002/ijc.29410 · 5.01 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Natural killer (NK) cells are an important effector cell type for adoptive cancer immunotherapy. Similar to T cells, NK cells can be modified to express chimeric antigen receptors (CARs) to enhance antitumor activity, but experience with CAR-engineered NK cells and their clinical development is still limited. Here, we redirected continuously expanding and clinically usable established human NK-92 cells to the tumor-associated ErbB2 (HER2) antigen. Following GMP-compliant procedures, we generated a stable clonal cell line expressing a humanized CAR based on ErbB2-specific antibody FRP5 harboring CD28 and CD3? signaling domains (CAR 5.28.z). These NK-92/5.28.z cells efficiently lysed ErbB2-expressing tumor cells in vitro and exhibited serial target cell killing. Specific recognition of tumor cells and antitumor activity were retained in vivo, resulting in selective enrichment of NK-92/5.28.z cells in orthotopic breast carcinoma xenografts, and reduction of pulmonary metastasis in a renal cell carcinoma model, respectively. ?-irradiation as a potential safety measure for clinical application prevented NK cell replication, while antitumor activity was preserved. Our data demonstrate that it is feasible to engineer CAR-expressing NK cells as a clonal, molecularly and functionally well-defined and continuously expandable cell therapeutic agent, and suggest NK-92/5.28.z cells as a promising candidate for use in adoptive cancer immunotherapy.Molecular Therapy (2014); doi:10.1038/mt.2014.219.