Assignment of the NAD-dependent deacetylase sirtuin 5 gene (SIRT5) to human chromosome band 6p23 by in situ hybridization

Sirtuin 5 (SIRT5) is a nicotinamide adenine dinucleotide (NAD+)-dependent deacetylase and belongs to the Silent information regulator 2 (Sir2) family of sirtuin histone deacetylases (HDACs), which play a central role in epigenetic gene silencing, DNA repair and recombination, cell-cycle, microtubule organization, and in the regulation of aging. We have isolated and characterized the human SIRT5 genomic sequence, which spans a region of 28,182 bp and which has one single genomic locus. Human SIRT5 consists of eight exons and is found in two isoforms, which encode a 310 aa and a 299 aa protein, respectively. Human SIRT5 is most predominantly expressed in heart muscle cells and in lymphoblasts. Fluorescence in situ hybridization analysis localized the human SIRT5 gene to chromosome 6p23.

Piperacillin/tazobactam vs ceftazidime in the treatment of neutropenic fever in patients with acute leukemia or following autologous peripheral blood stem cell transplantation: a prospective randomized trial

Piperacillin/tazobactam was compared with ceftazidime for the empirical treatment of febrile neutropenia in patients with acute leukemia or following autologous peripheral blood stem cell transplantation. Owing to inclusion criteria, it was possible for the same patient to be randomized several times. A total of 219 individual patients were admitted to a prospective randomized clinical study: 24 patients were included twice. Patients (23.5%) remained afebrile. Patients who developed febrile neutropenia were randomized to receive intravenous ceftazidime (n = 74 patients, group I) or piperacillin/tazobactam (n = 87 patients, group II). Response to first-line antibiotic treatment was seen in 55% (group I) and 53% (group II). After the addition of vancomycin, a further 19% (group I) and 24% (group II) of the patients became afebrile. Causes of fever were: microbiologically documented infection in 36 and 34 patients of group I and II; Clostridium difficile in eight and 12 patients of group I and II, and fever of unknown origin in 30 and 41 patients of group I and II. One patient died in each group. Single-agent therapy with piperacillin/tazobactam is as effective as ceftazidime in the treatment of neutropenic fever and is well tolerated. Direct and indirect costs of both treatment regimes are equivalent.

Bone marrow niche and leukemia

Mounting evidence indicates that human cancers may originate from malignant transformation of stem cells. The most convincing proof is found in acute myeloid leukemia, where only a small subset of slowly dividing cells was able to induce transplantable acute myeloid leukemia. Normal hematopoietic stem cells (HSC) are characterized by their unlimited ability to self-renew, give rise to a multitude of cells that exhibit more differentiated features, and show slow division kinetics. Using human HSC and mesenchymal stromal cells (MSC) as models, we and others have demonstrated the vital role of the cellular niche in maintaining the self-renewing capacity, that is, "stemness" of HSC. Without direct contact with the cellular niche, HSC tend to differentiate and lose their stemness. Similar to their normal counterparts, leukemia stem cells divide slowly and maintain their self-renewal capacity through interaction with the niche. As a consequence, they are resistant to conventional chemotherapy strategies that target rapidly dividing cells. Thus it is of utmost importance to understand the interaction between cellular niche and normal HSC as well as between leukemia stem cells and the niche to provide a basis for more efficient treatment strategies.

Autologous haematopoietic stem cell transplantation for Behcet's disease with pulmonary involvement: analysis after 5 years of follow up

BACKGROUND

Myeloablative chemotherapy and autologous haematopoietic stem cell transplantation (HSCT) may provide a therapeutic option in severe Behçet's disease (BD) with pulmonary involvement.

CASE REPORTS

Two patients with BD with pulmonary involvement refractory to conventional immunosuppressive treatment underwent HSCT 1999. Stem cells were mobilised with cyclophosphamide (2 and 4 g/m(2)) and subsequently enriched ex vivo for CD34+ cells. The conditioning regimen used was melphalan (200 mg/m(2)). Outcome was measured by improvement of clinical features, function of affected organs, serological markers, need for immunosuppressive chemotherapy after transplant, and relapse. In both cases HSCT was successful, with good response and without serious complications. After 5 years of follow up one patient is in complete remission without immunosuppressive drugs and one has partial remission, needing low dose corticosteroids (8 mg/day).

CONCLUSION

In these two patients myeloablative chemotherapy, followed by HSCT could be performed safely with marked improvement. In comparison with other observational studies the duration of more than 5 years of remission is remarkable, and its full duration is still unknown.

Long-term outcome of nonmyeloablative allogeneic transplantation in patients with high-risk multiple myeloma

Conventional treatment or autologous transplantation has not been able to achieve long-term remission in patients with multiple myeloma (MM). Nonmyeloablative allogeneic transplantation might offer an option for cure without the high mortality associated with conventional conditioning. Here we present a retrospective analysis of patients with high-risk MM treated with nonmyeloablative allogeneic transplantation. In all, 52 patients with relapsed MM or high-risk features at diagnosis received 2 Gy TBI alone (n=3) or with fludarabine (n=49) as conditioning. Patients were heavily pretreated with a median of eight cycles of conventional chemotherapy and one or more autologous transplants for all but one patient. Regimen-related toxicity was low. Acute graft-versus-host disease II-IV occurred in 37% of patients, and 70% experienced chronic graft-versus-host disease (cGvHD). Median follow-up was 567 days, and transplant-related mortality was 17% in total. Estimated progression-free and overall survival at 18 months was 29.4 and 41.1%, respectively. Patients with cGvHD had a significantly higher progression-free survival, as did patients with up to eight cycles of pretreatment chemotherapy vs those with nine or more. In this highly pretreated patient group, disease control was unsatisfactory and our results suggest that a potential strategy might be to perform allogeneic transplant earlier in the course of the disease.

Integriertes Skills-Lab-Konzept für die studentische Ausbildung in der Inneren Medizin

BACKGROUND AND OBJECTIVE

An amendment to the German medical curriculum in April 2002 will place basic practical skills at the centre of medical training. We report here on the implementation and evaluation of an obligatory, tutor-guided, and integrated skills laboratory concept in the field of internal medicine.

METHODS

To test the effectiveness of a skills laboratory training on OSCE performance a pilot study was carried out. The experimental group, of 77 students, participated in seven sessions of communication training, skills laboratory training, and bedside teaching, each lasting one and a half hours. The control group of 66 students had as many sessions but was only offered bedside-teaching. The evaluation of acceptance of skills' training as well as the related increase in individual competence is on-going (summer term 2004: n = 176 students).

RESULTS

The integrated skills laboratory concept was rated at 3.5 (SD = 1.2) on a 5-point scale and was acknowledged as practice-oriented (M = 4.2; SD = 1.0) and relevant for doctors' everyday lives (M = 3.6; SD = 1.1). Increased levels of competence according to individual self-evaluations proved to be highly significant (p<.001), and results of the pilot study showed that the experimental group had a significantly better OSCE performance than the control group (p<.001).

CONCLUSION

This pilot study shows that curriculum changes promoting basic clinical skills are effective and lead to an improved practical education of tomorrow's physicians. The integrated skills laboratory concept is well accepted and leads to a relevant increase in competence in the practice of internal medical. The presented skills laboratory concept in internal medicine is proving to be a viable and efficient learning tool.

Molecular monitoring of tumour load kinetics predicts disease progression after non-myeloablative allogeneic stem cell transplantation in multiple myeloma

BACKGROUND

Non-myeloablative allogeneic stem cell transplantation followed by immunomodulatory therapies is considered a potentially curative approach in the treatment of multiple myeloma and most effective in a minimal residual disease setting.

PATIENTS AND METHODS

The aim of this study was to find the most sensitive real-time PCR assay (TaqMan), based on the IGH rearrangement, to quantify the tumour load of 11 patients with multiple myeloma after non-myeloablative allogeneic transplantation. Patient-allele specific primers (ASO) and the TaqMan probe were derived from CDR2 and CDR3 hypervariable regions of IGH, while consensus primers were located within the FR3 and FR4/JH regions. Four different approaches of primer combinations were tested.

RESULTS

ASO-forward and -reverse primers together with the clone-specific TaqMan probe were the most sensitive approach compared with the JH (P=0.071) or the FR3 consensus primer (P <0.001). The detection limit amounted to 1/10(4)-1/10(5) cells. Consecutively, 120 samples from 11 patients prior and post allogeneic transplantation were analysed. Three patients reached complete clinical remission accompanied by molecular remission. Disease progression or relapse was seen in six patients. In five, molecular progressive disease was detected prior to the clinical diagnosis of progression or relapse.

CONCLUSION

Patient-specific real-time IGH-PCR provides the opportunity for earlier treatment intervention.

Thrombotic microangiopathy after combined autografting-allografting for multiple myeloma - report of three cases

Thrombotic microangiopathy (TMA) has been described as a complication of bone marrow or stem cell transplantation. It is usually associated with high dose therapy for autologous transplantation or myeloablative conditioning in the allogeneic setting. Here we report three cases of TMA after reduced intensity conditioning and allogeneic peripheral blood stem cell transplantation. All three patients had high dose Melphalan therapy with autologous stem cell support preceding the allogeneic transplantation for several weeks, which may have contributed to endothelial damage and subsequent development of TMA.

Myeloablative conditioning in myelofibrosis using i.v. treosulfan and autologous peripheral blood progenitor cell transplantation with high doses of CD34+ cells results in hematologic responses - follow-up of three patients

Autologous transplantation after myeloablation for myelofibrosis with myeloid metaplasia provides a palliative therapy with a long term relief of symptoms. We have transplanted three patients with more than 5 x 10(6) CD34+ cells/kg body weight after myeloablation with treosulfan (total dose 42 g/m(2)) with a 18 months follow-up. Two of the patients had symptomatic splenomegaly and severe anemia. One patient had symptomatic splenomegaly and thrombocytopenia (< 100x10(9)/L). Granulocyte colony-stimulating factor-supported peripheral blood progenitor cell mobilization and collection was not associated with increased toxicity. Following transplantation we observed a prolonged reconstitution period of 28-38 days without fever or severe mucositis. All patients became free of erythrocyte transfusions or recovered to normal thrombocyte counts. There was a significant reduction of max. spleen size in one patient. We conclude that myeloablation with treosulfan and autologous PBPCT in these three patients with myelofibrosis was safe and useful.

New developments in stem cell biology and therapy. meeting report from the working group of the German Society for Hematology and Oncology

The call for the meeting which took place in Heidelberg 13 January 2005, resulted in a high number of contributions covering a diversity of topics: embryonal stem cell research; molecular signaling pathways; assay systems for primitive, mesenchymal and epithelial stem cells; markers for transdifferentiation; and theoretical considerations including biomathematical modeling of stem cell development. The program was rounded off by pre-clinical and clinical applications of stem cell therapies, including new mobilization agents, treatment of myocardial infarction and chemoprotective gene transfer to stem cells.

Micrometastatic bone marrow cells at diagnosis have no impact on survival of primary breast cancer patients with extensive axillary lymph node involvement treated with stem cell-supported high-dose chemotherapy

BACKGROUND

To determine the impact of micrometastatic bone marrow cells (MMC) on survival in high-risk primary breast cancer (HRPBC) patients treated with high-dose chemotherapy (HDCT) and autologous stem cell transplantation (ASCT).

PATIENTS AND METHODS

Ninety-one HRPBC patients (73 patients with > or =10 involved axillary lymph nodes (ALN), 18 premenopausal women with > or =4 involved ALN) received one cycle (eight patients) or two cycles of HDCT and ASCT. Bone marrow aspiration was performed before systemic treatment to search for MMC using a cocktail of four monoclonal epithelial-specific antibodies (5D3, HEA125, BM7 and BM8). The influence of MMC and other prognostic factors on disease-free survival (DFS), distant DFS (DDFS), and overall survival (OS) was analysed.

RESULTS

In 23 of 91 patients (25%) we detected a median of three MMC (range, 1-43) among 10(6) mononuclear cells. With a median follow-up of 62 months (range, 10-117), the detection of MMC was not associated with DFS (P=0.929), DDFS (P=0.664) or OS (P=0.642). In multivariate analysis the strongest predictor was nodal ratio for DFS (P=0.012) and expression of p53 for OS (P <0.001).

CONCLUSION

The detection of MMC at diagnosis has no impact on survival in HRPBC patients treated with HDCT and ASCT.

Albumin-coupled methotrexate (MTX-HSA) is a new anti-arthritic drug which acts synergistically to MTX

OBJECTIVE

To evaluate the anti-arthritic effects of the new inflammation-targeted drug MTX-HSA and to investigate whether peripheral blood mononuclear cells (PBMC) are potential target cells for albumin-mediated drug delivery.

METHODS

The murine model of collagen-induced arthritis (CIA) was used to measure the anti-arthritic effect of MTX, MTX-HSA or a combination of both (n = 30 to 35 per group). In addition, the uptake of fluorescence-labelled albumin (AFLc-HSA) in PBMC of 14 patients with RA was measured by fluorescence-activated cell sorting (FACS).

RESULTS

In equivalent doses of 7.5 mg/kg intravenously (IV) twice a week, MTX-HSA is significantly (P<0.02) superior to MTX in inhibiting the development of CIA and reducing the joint count as well as the number of affected paws. When given in lower doses as combination therapy, both drugs act synergistically (P<0.03). A mean of 96, 72 and 64% of the CD14-, CD16- and CD20-positive cells from peripheral blood of rheumatoid arthritis (RA) patients showed an uptake of albumin after incubation with AFLc-HSA in vitro. This finding was not significantly different in comparison to healthy controls. In contrast, the number of CD3-positive cells taking up albumin is increased significantly in RA patients in comparison to controls (26.3 +/- 12.9% s.d. vs 11.6 +/- 7.3% s.d.; P = 0.005).

CONCLUSION

The data show that the effectiveness of MTX-HSA in CIA is superior to MTX and that both drugs act synergistically. In addition, albumin appears to be taken up by peripheral blood cells, suggesting that they might be one of the potential target cells of this novel anti-arthritic treatment approach.

High-dose chemotherapy with autologous peripheral blood stem cell transplantation for bone and soft-tissue sarcomas

The role of high-dose chemotherapy (HDCT) with PBSCT in the treatment of bone and soft-tissue sarcomas is not established. In total, 27 patients (15 female, median age at TPL 30.6 years (range: 13-59)) were analyzed (Ewing sarcoma family n=8, osteosarcoma n=6, MPNST (malignant peripheral nerve sheath tumor) n=4, synovial sarcoma n=3, liposarcoma n=2, leiomyosarcoma n=2, rhabdomyosarcoma n=1, meningosarcoma n=1). Following chemotherapy and surgery complete remission (CR) (n=9), partial remission (PR) (n=10), stable disease (SD) (n=2) and progressive disease (PD) (n=6) were reached prior HDCT. Different HDCT conditioning regimens were used. One patient died due to cardiac arrest after HDCT. Except hematologic side effects, no WHO grade III-IV complications were observed. Four patients died within 6 months due to PD, disease recurred in another seven patients and led to death, 15 patients are alive with/without disease. The median progression-free survival (PFS) is 12.0 months (range: 0-58), in nine CR patients median PFS is 25.8 months (range: 3-58). Although the role of HDCT in the treatment of sarcomas is not defined, a subgroup of patients who achieved CR before HDCT could benefit from this therapy.

Remarkable response to rituximab in a patient with atypical CD20 ++ mantle cell lymphoma of the bone marrow leading to severe pancytopenia

Rituximab, a chimeric monoclonal antibody which binds to the CD20 antigen, has been reported in several studies to induce remissions in low- and high-grade non-Hodgkin's lymphoma without causing myelosuppression. We report here a case of a 68-year-old female patient with an atypical mantle cell lymphoma infiltrating only the bone marrow without leukemic involvement or any other nodal or extranodal manifestations. Progressive severe pancytopenia due to the diffuse bone marrow infiltration led to life-threatening infections following oral chlorambucil treatment. No response to chlorambucil was noted. The patient attained a complete remission after salvage therapy with four weekly infusions of single-agent rituximab at a standard dose of 375 mg/m(2). Thus, anti-CD20 antibody may be the treatment of choice for patients with CD20(+) B-non-Hodgkin's lymphoma who cannot tolerate chemotherapy due to high risk of infectious complications as a result of severe pancytopenia.

Antiangiogenic Therapy in Hematologic Malignancies

Angiogenesis is defined as the formation of new capillaries from prexisting blood vessels and plays an important role in the progression of solid tumors and hematologic malignancies. Markers of angiogenesis correlate with clinical characteristics in leukemia and non-Hodgkin's-lymphoma, serving as predictors of poor prognosis. Antiangiogenic effects of chemotherapeutics as well as of novel drugs such as farnesyltransferase inhibitors and tyrosine kinase inhibitors such as Gleevec might contribute to their therapeutic potential. Thalidomide which has antiangiogenic effects and direct cytotoxic effects was found to be effective in multiple myeloma and is considered as an established treatment modality for patients with refractory or relapsed multiple myeloma. Thalidomide has a significant therapeutic effect in myelodysplastic syndrome (MDS) by improving cytopenia and achieving independence of transfusion therapy in a subset of patients. Preliminary data indicate activity of specific VEGF receptor tyrosine kinase (RTK) inhibitors in multiple myeloma (MM) and acute myeloid leukemia (AML). The positive correlation between increased levels of angiogenic cytokines and clinical response to VEGF-RTK inhibitors and thalidomide indicates the relevance of detecting angiogenesis markers to identify best candidate patients for specific approaches. Including antiangiogenic drugs into treatment protocols for hematologic malignancies is an important task for future clinical studies.

Centrosome aberrations as a possible mechanism for chromosomal instability in non-Hodgkin's lymphoma

Recently, centrosome aberrations have been described as a possible cause of aneuploidy in many solid tumors. To investigate whether centrosome aberrations occur in non-Hodgkin's lymphoma (NHL) and correlate with histologic subtype, karyotype, and other biological disease features, we examined 24 follicular lymphomas (FL), 18 diffuse large-B-cell lymphomas (DLCL), 33 mantle cell lymphomas (MCL), and 17 extranodal marginal zone B-cell lymphomas (MZBCL), using antibodies to centrosomal proteins. All 92 NHL displayed numerical and structural centrosome aberrations as compared to nonmalignant lymphoid tissue. Centrosome abnormalities were detectable in 32.3% of the cells in NHL, but in only 5.5% of lymphoid cells from 30 control individuals (P<0.0001). Indolent FL and MZBCL contained only 25.8 and 28.8% cells with abnormal centrosomes. In contrast, aggressive DLCL and MCL harbored centrosome aberrations in 41.8 and 35.0% of the cells, respectively (P<0.0001). Centrosomal aberrations correlated to lymphoma grade, mitotic, and proliferation indices, but not to the p53 labeling index. Importantly, diploid MCL contained 31.2% cells with abnormal centrosomes, while tetraploid samples harbored centrosome aberrations in 55.6% of the cells (P<0.0001). These results indicate that centrosome defects are common in NHL and suggest that they may contribute to the acquisition of chromosomal instability typically seen in NHL.

Peripherally inserted central venous catheters for autologous blood progenitor cell transplantation in patients with haematological malignancies

BACKGROUND

In contrast to the high risk of haemorrhage associated with the implantation of a central venous catheter (CVC) via the internal jugular or subclavian access, the use of a peripherally inserted catheter (PICC) offers the advantage of a lower risk of bleeding complications. However, the rate of phlebitis is higher with the PICC and its use has been declining. We have studied the benefits and adverse events of a new type of PICC and a common type.

METHODS

From October 1999 to October 2001, 70 PICCs (Olimpicc, Vygon, Germany, n=40; and LIFECATH-PICC(PUR)5FR Vygon, Germany, n=30) were inserted into 66 patients with haematological malignancies and used for high-dose chemotherapy, total parenteral nutrition and autologous blood stem cell transplantation. While removing the catheter, central and peripheral blood cultures were taken. The catheter tip was investigated by the semi-quantitative roll-out method of Maki.

RESULTS

Sixty-five PICCs were removed after a median of 8.9 days. In five cases a catheter-associated significant colonisation with coagulase-negative staphylococci occurred. In two instances catheter-related bacteraemia was found.

CONCLUSION

In our study this catheter system was inserted in 94% of patients without problems and showed a low incidence of phlebitis (5/65). Because of the high rate of catheter malfunction reported during and after our study, the Olimpicc catheter is no longer available. The PICC system, and the LIFECATH-PICC(PUR)5FR in particular, offers a safe and effective alternative for central venous access to the internal jugular vein.

Evidence of a graft-versus-leukemia effect in chronic lymphocytic leukemia after reduced-intensity conditioning and allogeneic stem-cell transplantation: the Cooperative German Transplant Study Group

PURPOSE

To study whether hematopoietic stem-cell transplantation (HSCT) after reduced-intensity conditioning is effective and tolerable in patients with advanced chronic lymphocytic leukemia (CLL).

PATIENTS AND METHODS

Thirty patients with advanced B-cell CLL were included into the study. After reduced-intensity conditioning with fludarabine, busulfan, and antithymocyte globulin, patients received a transplant from related (n = 15) or unrelated donors (n = 15). Minimal residual disease (MRD) was monitored with a clone-specific polymerase chain reaction.

RESULTS

After a median follow-up of 2 years, 23 patients are alive (to date). Neutrophil and platelet engraftment occurred after a median of 17.5 and 15 days, respectively. Acute graft-versus-host disease (GVHD) grade 2 to 4 was observed in 17 patients (56%), and chronic GVHD was observed in 21 patients (75%). Twelve patients (40%) achieved a complete remission (CR), and 16 patients (53%) achieved a partial remission. Late CR occurred up to 2 years after transplantation. MRD was monitored in eight patients with CR. All patients achieved a molecular CR. At last follow-up, six patients were in ongoing molecular CR. Causes of death were treatment-related complications in four patients and progressive disease in three patients. The probability of overall survival, progression-free survival, and nonrelapse mortality at 2 years was 72% (95% confidence interval [CI], 54% to 90%), 67% (95% CI, 49% to 85%), and 15% (95% CI, 1% to 29%), respectively.

CONCLUSION

Treatment-related mortality after reduced-intensity conditioning followed by allogeneic HSCT was low. The procedure induced molecular remissions in patients with advanced CLL. The observation of late remissions provided evidence of a graft-versus-leukemia effect.