Efficacy of haematopoietic stem cell boost as a rescue for poor graft function after haematopoietic stem cell transplantation: A multicentre retrospective study on behalf of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC).

Haematopoietic stem cell reinjection may be a curative option for poor graft function after haematopoietic stem cell transplantation; however, literature supporting its use remains limited. We conducted a multicentre retrospective study on behalf of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy, including 55 patients. We demonstrated response rates of nearly 40% and two-year survival of more than 60% in the context of an otherwise deadly complication and we observed that the timing of injection and the degree of cytopenia are strongly associated with outcomes. This study shows the feasibility of the procedure informing on its epidemiology, outcomes and prognostic factors, setting the stage for future guidelines.

[Treatment of ITP and AIHA in CVID: A systematic literature review]. / Traitement du PTI et de l'AHAI au cours du DICV : revue systématique de la littérature.

INTRODUCTION: Ten to 15% of common variable immunodeficiencies (CVID) develop auto-immune hemolytic anemia (AIHA) and immune thrombocytopenia (ITP). Treatment is based on immunosuppressants, which produce blocking effects in the CVID. Our objective was to assess their risk-benefit ratio in these immunocompromised patients. METHODS: We identified 17 articles detailing the treatment of AIHA and/or ITP in patients suffering from CVID through a systematic review of the MEDLINE database. RESULTS: The increased infectious risk with corticosteroids does not call into question their place in the first line of treatment of ITP and AIHA in CVID. High-doses immunoglobulin therapy remain reserved for ITP with a high risk of bleeding. In second-line treatment, rituximab appears to be effective, with a lower infectious risk than the splenectomy. Immunosuppressants (azathioprine, methotrexate, mycophenolate, cyclophosphamide, vincristine, ciclosporine) are moderately effective and often lead to severe infections, meaning that their use is justified only in resistant cases and steroid-sparing. Dapsone, danazol and anti-D immunoglobulins have an unfavorable risk-benefit ratio. The place of TPO receptor agonists is still to be defined. The establishment of immunoglobulin replacement in the place of immunosuppressants (except for short-term corticotherapy) or splenectomy appears to be essential to limit the risk of infections, including in the absence of previous infections. CONCLUSION: The presence of CVID does not mean that it is necessary to give up on corticosteroids as a first-line treatment and rituximab as a second-line treatment for AIHA and ITP, but it should be in addition to immunoglobulin replacement. A splenectomy should be reserved as a third-line treatment.

Circulating Cd34+ cell count differentiates primary myelofibrosis from other Philadelphia-negative myeloproliferative neoplasms: a pragmatic study.

A high number of circulating CD34+ cells has been advocated to distinguish primary myelofibrosis from other Philadelphia-negative myeloproliferative neoplasms. We re-evaluated the diagnostic interest of measuring circulating CD34+ cells in 26 healthy volunteers and 256 consecutive patients at diagnosis for whom a myeloproliferative neoplasm was suspected. The ROC curve analysis showed that a number of CD34+ <10/µl excludes the diagnosis of primary myelofibrosis with a sensitivity of 97 % and a specificity of 90 % (area under the curve: 0.93 [0.89-0.98]; p < 0.001). Patients with PMF harboring a CALR mutation had more circulating CD34+ cells than patients with either a JAK 2 or MPL mutation (p = 0.02 and p < 0.01, respectively). These results suggest that this fast, simple, non-invasive, and standardized test is of particular interest to exclude the diagnosis of primary myelofibrosis.

Miconazole mucoadhesive buccal tablet in high-dose therapy with autologous stem cell transplantation (HDT/ASCT)-induced mucositis.

Oral mucositis is a major cause of morbidity in high-dose therapy/autologous stem cell transplantation (HDT/ASCT), where microbial colonization has an important pathological implication. In this study, we evaluated the impact of miconazole mucoadhesive buccal tablet (MBT) on mucositis-related complications. During two consecutive 34-month periods, patients treated with HDT/ASCT in our hematology department received either miconazole MBT (60 patients) or conventional oral amphotericin B suspensions three times a day (44 patients) in order to prevent or decrease chemotherapy-induced mucositis. The use of miconazole MBT is associated with less infectious complications as indicated by shorter antibiotic use (7.8 vs. 12.3 days; p < 0.0001), shorter intravenous antifungal use (1.4 vs. 3.6 days; p = 0.02), and a trend towards less yeast contamination in stool samples. Less patients required any analgesic drugs during hospitalization in the miconazole MBT group (18 vs. 7 %; p = 0.09). Indirect indicators of chemotherapy-induced mucositis (duration of hospitalization, morphine use) were in favor of miconazole MBT in patients with multiple myeloma (MM) but not for those with lymphoma. This study suggests that miconazole MBT provides a valid alternative to oral amphotericin B suspensions in regards to mucositis-related complications. A prospective and randomized study is warranted to establish the definite role of miconazole MBT.

Identification of an RNA binding specificity for the potential splicing factor TLS.

The TLS/FUS gene is involved in a recurrent chromosomal translocation in human myxoid liposarcomas. We previously reported that TLS is a potential splicing regulator able to modulate the 5'-splice site selection in an E1A pre-mRNA. Using an in vitro selection procedure, we investigated whether TLS exhibits a specificity with regard to RNA recognition. The RNAs selected by TLS share a common GGUG motif. Mutation of a G or U residue within this motif abolishes the interaction of TLS with the selected RNAs. We showed that TLS can bind GGUG-containing RNAs with a 250 nm affinity. By UV cross-linking/competition and immunoprecipitation experiments, we demonstrated that TLS recognizes a GGUG-containing RNA in nuclear extracts. Each one of the RNA binding domains (the three RGG boxes and the RNA recognition motif) contributes to the specificity of the TLS.RNA interaction, whereas only RRM and RGG2-3 participate to the E1A alternative splicing in vivo. The specificity of the TLS.RNA interaction was also observed using as natural pre-mRNA, the G-rich IVSB7 intron of the beta-tropomyosin pre-mRNA. Moreover, we determined that RNA binding specificities of TLS and high nuclear ribonucleoprotein A1 were different. Hence, our results help define the role of the specific interaction of TLS with RNA during the splicing process of a pre-mRNA.

Inactivation of p53 in normal human cells increases G2/M arrest and sensitivity to DNA-damaging agents.

p53 mutations are found in about 70% of human cancers. In order to evaluate the role of these mutations in response to chemotherapeutic agents, it is important to distinguish between p53 response to DNA-damaging agents in normal and in tumour cells. Here, using normal human fibroblasts (NHFs), we show that cisplatin and UV radiation induce G2/M arrest which is temporally linked to p53-protein induction. To study the contribution of p53 to this G2/M arrest, we inhibited p53 induction in NHFs using p53 anti-sense oligonucleotides. Following exposure of NHFs to UV radiation, the inhibition of p53-protein induction leads to a greater accumulation of cells in the G2/M phase, but also to a decreased fraction of cells in the G1 phase. We propose that p53 does not induce G2/M arrest directly, and that the extent of this arrest may depend on the fraction of cells that do not stop at the G1 phase following exposure to DNA-damaging agents. Furthermore, inhibition of p53-protein induction leads to increased sensitivity of NHFs to UV radiation. These results suggest that inhibition of p53 protein enhances sensitivity to DNA-damaging agents in normal human cells.

Thrombin receptor-mediated increase of two matrix metalloproteinases, MMP-1 and MMP-3, in human endothelial cells.

Matrix metalloproteinases (MMPs) are responsible for the degradation of extracellular matrix components and are secreted by a variety of cells including human endothelial cells. Because alpha-thrombin is known to interact with matrix components and has been shown to activate latent MMP-2 in human umbilical vein endothelial cells, we investigated whether human alpha-thrombin could also regulate other MMPs secreted by the human saphenous vein or mammary artery endothelial cells (EC). After treatment of EC with increasing concentrations of thrombin for different periods of time, a significantly higher gelatinolytic activity of both MMP-1 and MMP-3 was observed in addition to MMP-2 activation. The effect of thrombin was time and dose-dependent, reaching a maximum at 24 hours. After treatment with 5 NIH U/ml thrombin for 24 hours, Western blotting revealed 9.5- and 4.4-fold increases over control values for MMP-3 and MMP-1, respectively. The synthetic thrombin receptor agonist peptide SFLLRNPNDKYEPF fully reproduced the action of thrombin, whereas chemical inactivation of the catalytic site of thrombin abolished its effect on MMP-1 and MMP-3. Thrombin and SFLLRNPNDKYEPF both induced MMP-3 mRNA synthesis but had no significant influence on constitutive MMP-1 mRNA levels. These results demonstrate that thrombin not only activates latent MMP-2 but also modulates MMP-1 and MMP-3 production in EC, this latter effect being mediated by the G-protein-coupled thrombin receptor. Hence, our present data provide evidence to support the suspected role of thrombin in tissue remodeling and angiogenesis.

Angiogenesis inhibitor SR 25989 upregulates thrombospondin-1 expression in human vascular endothelial cells and foreskin fibroblasts.

The aim of this work was to evaluate the effects of SR 25989, a member of the thienopyridine family devoid of antiplatelet activity but possessing anti-angiogenic properties, on the regulation of proteins involved in matrix remodeling during wound healing or tumor progression. Human endothelial cells grown in the presence of SR 25989 showed moderate increases in the production of activators (tissue plasminogen activator and urokinase) and one inhibitor (plasminogen activator inhibitor type 1) of fibrinolysis, together with a significant rise in intracellular thrombospondin-1. SR 25989 induced a similar increase in thrombospondin-1 in human foreskin fibroblasts. This over-expression of thrombospondin-1 was correlated to a decrease in cell density. A concomitant increase in the tumor suppressor gene protein p53 was observed in endothelial cells and in fibroblasts, in which the slowing down of proliferation could be related to an accumulation of cells in the S and G2/M phases of the cell cycle. Northern blot analysis revealed a temporary rise in thrombospondin-1 transcripts, followed by a decrease along with a moderate increase in p53 transcripts. Thus the anti-angiogenic properties of SR 25989 appear to result from an upregulation of thrombospondin-1 which is possibly mediated by p53. The thienopyridine SR 25989 could therefore be a good candidate for adjuvant anti-angiogenic therapy in cancer.

PF4 inhibits thrombin-stimulated MMP-1 and MMP-3 metalloproteinase expression in human vascular endothelial cells.

We investigated whether PF4 could regulate the constitutive and thrombin-stimulated expression of metalloproteinases (MMPs) in endothelial cells (EC). PF4 inhibited the increase in the expression of MMP-1 and MMP-3 promoted by thrombin or the thrombin receptor agonist peptide SFLLRNPNDKYEPF (SFLL..) by 50% but did not modify the constitutive expression of these MMPs. This inhibitory effect was not mediated through a direct interaction of PF4 with thrombin or with the MMPs themselves. The interaction of PF4 with heparan sulfates at the surface of the EC appeared to be implicated in the inhibition mechanism of MMP-1 but not in that of MMP-3. MMP-1 transcription levels remained unchanged after PF4 treatment, whereas the increase in MMP-3 transcription induced by thrombin or SFLL.. was inhibited by approximately 50%. Expression of the tissue inhibitors of metalloproteinases TIMP-1 and TIMP-2 was not affected by PF4. The present data provide new evidence that the antiangiogenic properties of PF4 involve the inhibition of matrix breakdown and suggest that this property of PF4 could be especially relevant in the context of thrombin-regulated tissue remodelling.