Reversine increases multipotent human mesenchymal cells differentiation potential

Among different human stem cell sources, adult mesenchymal stem cells from bone marrow (BMSCs), and more recently from adipose tissues (ASCs), have shown their capability to differentiate into a variety of different cell types, including osteoblasts, adipocytes, and muscle cells. However, mesenchymal stem cell differentiation toward certain cell types (including skeletal and cardiac muscle), while shown to be achievable, still suffers of low yields and needs to be greatly improved before any therapeutic application could be foreseen. A possible way of achieving this goal is by using a chemical-pharmacological approach to increase stem cell plasticity. Along this line, we envisioned the possibility of pre-treating BMSCs and ASCs with reversine, a synthetic purine that has been shown to induce adult cells de-differentiation. In the current study we tested reversine effects on both BMSCs and ASCs to increase their differentiation toward osteoblasts, smooth and skeletal muscle cells. Reversine pre-treatment, at very low concentration (50 nM), caused a marked increase in the differentiation yields of both BMSCs and ASCs.

Risk factors for invasive aspergillosis and related mortality in recipients of allogeneic SCT from alternative donors: an analysis of 306 patients

Invasive aspergillosis (IA) is a serious complication in patients undergoing allogeneic haematopoietic stem cell transplantation (HSCT), particularly from donors other than HLA-identical sibling. All 306 patients who underwent alternative donor HSCT between 01 January 1999 and 31 December 2006 were studied. Late IA was defined as occurring >or=40 days after HSCT. The median follow-up was 284 days (range, 1-2709). Donors were matched unrelated (n=185), mismatched related (n=69), mismatched unrelated (n=35) and unrelated cord blood (n=17). According to European Organization for Research and Treatment of Cancer/Mycoses Study Group criteria, 2 patients already had IA at HSCT, 23 had early IA and 20 had late IA (IA incidence 15%). Eight patients had proven and 37 probable IA. Multivariate analyses showed that significant predictors of IA were delayed neutrophil engraftment, extensive chronic GVHD (cGVHD), secondary neutropenia and relapse after transplant. Early IA was associated with active malignancy at HSCT, CMV reactivation and delayed lymphocyte engraftment. Late IA was predicted by cGVHD, steroid therapy, secondary neutropenia and relapse after HSCT. IA-related mortality among IA patients was 67% and was influenced by use of anti-thymocyte globulin, steroids, higher levels of creatinine, and lower levels of IgA and platelets. The outcome of IA depends on the severity of immunodeficiency and the status of the underlying disease.

Improved outcome in young adults with de novo acute myeloid leukemia in first remission, undergoing an allogeneic bone marrow transplant

We assessed the outcome of 170 patients with AML in first complete remission, aged 1-47 years (median 29), who had undergone an allogeneic BMT before or after 1990 (n=80 and n=90, respectively); all patients were prepared with cyclophosphamide and TBI; the median follow-up for surviving patients was 13 years. The donor was an HLA-identical sibling in 164 patients. Transplant-related mortality (TRM) was 30% before and 7% after 1990 (P<0.001); relapse-related death (RRD) was 26 and 11% (P=0.002); and actuarial 10-year survival was 42 and 79% (P<0.00001). Patients transplanted after 1990 were older, had a shorter interval diagnosis-BMT, had less FAB-M3 cases, received a higher dose of TBI, a higher marrow cell dose and combined (cyclosporine+methotrexate) GVHD prophylaxis. Patients relapsing after transplant had an actuarial survival of 0 vs 31% if grafted before or after 1990 (P=0.01), and their median follow-up exceeds 10 years. In conclusion, the overall survival of first remission AML undergoing an allogeneic BMT has almost doubled in the past two decades, despite older age and fewer M3 cases. Improvement has come not only from changes in transplant procedures, but also from effective rescue of patients relapsing after transplant.

Allogeneic hemopoietic stem cell transplants for patients with relapsed acute leukemia: long-term outcome

We assessed the long-term outcome of patients with relapsed acute myeloid (n=86) or acute lymphoid leukemia (n=66), undergoing an allogeneic hemopoietic stem cell transplantation in our unit. The median blast count in the marrow was 30%. Conditioning regimen included total body irradiation (TBI) (10-12 Gy) in 115 patients. The donor was a matched donor (n=132) or a family mismatched donor (n=20). Twenty-two patients (15%) survive disease free, with a median follow-up of 14 years: 18 are off medications. The cumulative incidence of transplant related mortality is 40% and the cumulative incidence of relapse related death (RRD) is 45%. In multivariate analysis of survival, favorable predictors were chronic graft-versus-host disease (GvHD) (P=0.0003), donor other than family mismatched (P=0.02), donor age less than 34 years (P=0.02) and blast count less than 30% (P=0.07). Patients with all four favorable predictors had a 54% survival. In multivariate analysis of relapse, protective variables were the use of TBI (P=0.005) and cGvHD (P=0.01). This study confirms that a fraction of relapsed leukemias is cured with an allogeneic transplant: selection of patients with a blast count <30%, identification of young, human leukocyte antigen-matched donors and the use of total body radiation may significantly improve the outcome.

Progenitor cells trapped in marrow filters can reduce GvHD and transplant mortality

A bone marrow harvest is filtered either in the operating room, in the laboratory or during infusion to the patient. Filters are usually discarded. Little is known of haemopoietic progenitor cells (HPCs) trapped in the filters. The aim of the study was to evaluate HPC content in the filters and to assess the outcome of transplants with filter-discarded or filter-recovered cells. Haemopoietic progenitors were grown from filters of 19 marrow transplants. We then compared the outcome of 39 filter-recovered transplants from HLA-identical siblings (years 2001-2004) with a matched cohort of 43 filter-discarded marrow grafts (years 1997-2000). Filters contained on average 21% long-term culture-initiating cells (LTC-IC) and 15% fibroblasts colony-forming units (CFU-F) of the total progenitor cell content. Filter-discarded transplants had significantly more grade II-IV graft-versus-host disease (GvHD) (42 vs 15%, P=0.008) as compared to filter-recovered transplants, and more transplant-related mortality (TRM) (20 vs 3%, P=0.04). The actuarial survival at 5 years is 69 vs 87%, respectively (P=0.15). This study suggests that a significant proportion of LTC-IC is lost in the filters together with CFU-F. Recovery and add back of progenitors trapped in the filters may reduce GvHD and TRM.

Treatment of advanced mycosis fungoides by allogeneic stem-cell transplantation with a nonmyeloablative regimen

SUMMARY

Given the poor prognosis of patients with advanced cutaneous T-cell lymphoma and the high transplant-related mortality associated with conventional allogeneic bone marrow transplantation, we performed nonmyeloablative transplantation of allogeneic stem cells (ASCT) from HLA-identical siblings in three patients with this disease. All patients achieved full donor engraftment, clearance of clonal T cells leading to durable complete remissions but experienced high incidence of infections, which proved fatal in one case. These results suggest that nonmyeloablative ASCT is a novel and potentially curative therapy for patients with advanced T-cell lymphomas who have a histocompatible sibling.

Efficacy of N-acetylcysteine and all-trans retinoic acid in restoring in vitro effective hemopoiesis in myelodysplastic syndromes

We evaluated the in vitro effect on clonogenic potential (CFU-GM) and apoptosis in myelodysplastic syndromes (MDS) progenitors of an anti-oxidant (N-acetylcysteine, NAC) and/or a differentiating (all-trans retinoic acid, ATRA) agent. NAC significantly reduced apoptosis, both NAC and ATRA induced an increase in CFU-GM, but NAC seemed to be particularly effective in the high risk (HR) MDS. NAC + ATRA conferred a significant advantage in terms of CFU-GM with respect to NAC and ATRA alone. Tumor Necrosis Factor-alpha (TNF-alpha) levels decreased after incubation with NAC in the MDS samples. This study shows that ineffective hemopoiesis in MDS could benefit from both NAC and ATRA, suggesting that anti-oxidant treatment may play a role in guaranteeing MDS cell survival, predisposing them towards differentiation.

Low plasma stem cell factor levels correlate with in vitro leukemic growth in myelodysplastic syndromes

We evaluated the effect of SCF on myeloid differentiation by correlating clonogenic potential (as CFU-GM), bone marrow (BM) plasma SCF levels and CD34/c-kit expression in 57 MDS samples. There was a significant correlation between low SCF levels and 'leukemic' in vitro growth, the number of clusters and the colony/cluster ratio. No correlation was found between BM plasma SCF levels, the pattern of growth and CD34+ c-kit+ expression. These data seem to exclude any direct effect of SCF on leukemogenesis, but suggest that low plasma SCF levels may be at least partially responsible for leukemic growth in MDS.

Autologous bone marrow transplantation in advanced Hodgkin's disease

Autologous bone marrow transplantation (ABMT) has been proposed as an alternative treatment of resistant/refractory Hodgkin's disease (HD). Thirty-seven patients in various phases of HD underwent autografting in our Center: fourteen received a CBV conditioning regimen, the others BCNU or VP16 followed by cyclophosphamide and TBI. Three patients died before engraftment, 28 (75.67%) achieved CR and 6 showed persistent disease. As of March 1996, 18 patients had died and 13 were in continuous CR. The median event-free survival (EFS) and 3-year EFS chances were respectively 9 months and 31.3% in the series as a whole, 14 months and 40% in primary resistant disease, 9 months and 28.4% in responsive relapse, and 3 months and 22.2% in resistant relapse. As many of these patients had failed to respond to third-line therapies, their EFS figures are primarily attributable to the therapeutic efficacy of ABMT. Furthermore, since the EFS curves are better in patients seemingly characterized by a lower chance of chemoresistance, our data favour the use of ABMT in the earlier phases of HD.

Unrelated mismatched cord blood transplantation in an adult with secondary AML

Umbilical cord blood (CB) has been widely used for related and unrelated transplants in pediatric patients. We present the case of an adult with secondary AML who received an unrelated, one-antigen mismatched CB transplant due to the lack of a matched donor. The patient was a 26-year-old female (35 kg/bw) who had received an autologous bone marrow transplant for Hodgkin's disease in April 1994 and, 6 months later, developed secondary MDS (RAEB, 46, XX, -7, +mar), which slowly evolved into acute myelogenous leukemia. In May 1995, she was transplanted with a 165 ml CB unit containing a total of 1.6 x 10(9) nucleated cells, 11 x 10(6) CD34+ cells and 7.2 x 10(5) CFU-GM. GVHD prophylaxis consisted of standard CsA and methotrexate. Myeloid engraftment occurred on day +28 (PMN > 500) and full donor chimerism was confirmed twice (on days +33 and +56) by means of cytogenetics and DNA microsatellite analysis. Erythroid and megakaryocytic engraftment was documented by immunohistochemical analysis of a bone marrow biopsy on day +40, showing the presence of erythroblastic islands and isolated CD61+ immature cells. The patient did not develop GVHD but died on day +56 from idiopathic interstitial pneumonia and multiorgan failure. To our knowledge, this is one of the first case reports of unrelated mismatched CB transplantation in an adult.

Efficacy of different prophylactic antifungal regimens in bone marrow transplantation

BACKGROUND

Fungal infections still represent a major clinical problem in neutropenic patients; the recent availability of active imidazole derivatives, particularly fluconazole and itraconazole, has increased interest in prophylaxis.

MATERIALS AND METHODS

Fifty-nine consecutive bone marrow transplant (BMT) recipients were randomized to receive either itraconazole 400 mg/day or fluconazole 300 mg/day as oral antimycotic prophylaxis during the pancytopenic phase; they were retrospectively compared with a historical control group of 30 patients who had received fluconazole 50 mg/day. Every febrile episode was treated with the same empirical antibiotic combination; amphotericin-B was added after 4-5 days in the case of persistent fever. Proven or suspected mycotic infections and the empirical use of amphotericin-B were considered as failures of prophylaxis.

RESULTS

There were no differences in the number of febrile episodes in the three groups. Five patient died of bacterial sepsis: two in the fluconazole 300, two in the itraconazole and one in the fluconazole 50 group. The addition of amphotericin-B was required in 12, 16 and 11 cases, respectively, in the three groups. There were four documented fungal infections in the intraconazole and one in both fluconazole groups; three suspected fungal infections were observed in the fluconazole 300 group and two in both the itraconazole and the fluconazole 50 group. None of the differences were statistically significant.

CONCLUSIONS

The present results indicate that high-dose fluconazole and itraconazole are equivalent; neither of them was superior to low-dose fluconazole, which is regarded as being devoid of prophylactic activity against systemic mycoses.