The apoptogenic response of human myeloid leukaemia cell lines and of normal and malignant haematopoietic progenitor cells to the proteasome inhibitor PSI

Degradation of several intracellular proteins involved in cell cycle control and tumour growth is regulated by the ubiquitin-dependent multicatalytic protease complex (proteasome). We report that proteasome inhibitor Z-Ile-Glu(OtBu)-Ala-Leucinal (PSI) was cytotoxic on most human myeloid leukaemia cell lines at IC50 doses ranging from 5 to 25 nmol/l. Additionally, PSI pre-treatment enhanced cytotoxicity by taxol and cisplatinum. PSI was more active on leukaemic than on normal CD34(+) bone marrow progenitors because the 50% growth inhibition of colony-forming unit granulocyte macrophage (CFU-GM) from cases of chronic myelogenous leukaemia (CML) and normal subjects was achieved by 15 nmol/l and 50 nmol/l PSI respectively. PSI killed cells by apoptosis as revealed by ultrastructural changes, nuclear DNA fragmentation, cleavage of poly (ADP-ribose) polymerase (PARP) and of beta-catenin, and was antagonized by ectopic expression of Bcl-2 but not by inactivating mutations of p53. This event was associated with a slight accumulation of Bcl-2, a decrease of Bax but no changes in Bcl-X(L) protein expression at any time point. In Ph(+) cell lines BCR-ABL protein was only down-regulated after 48 h of treatment with 10 nmol/l PSI. Altogether, these results indicate that PSI, alone or in association with other cytotoxic agents, has anti-tumour activity against myeloid malignancies and is more effective on leukaemic than on normal haematopoietic progenitor cells.     

Cidofovir for cytomegalovirus infection and disease in allogeneic stem cell transplant recipients. The Infectious Diseases Working Party of the European Group for Blood and Marrow Transplantation

A retrospective study was performed to collect information regarding efficacy and toxicity of cidofovir (CDV) in allogeneic stem cell transplant patients. Data were available on 82 patients. The indications for therapy were cytomegalovirus (CMV) disease in 20 patients, primary preemptive therapy in 24 patients, and secondary preemptive therapy in 38 patients. Of the patients, 47 had received previous antiviral therapy with ganciclovir, foscarnet, or both drugs. The dosage of CDV was 1 to 5 mg/kg per week followed by maintenance every other week in some patients. The duration of therapy ranged from 1 to 134 days (median, 22 days). All patients received probenecid and prehydration. Ten of 20 (50%) patients who were treated for CMV disease (9 of 16 with pneumonia) responded to CDV therapy, as did 25 of 38 (66%) patients who had failed or relapsed after previous preemptive therapy and 15 of 24 (62%) patients in whom CDV was used as the primary preemptive therapy. Of the patients, 21 (25.6%) developed renal toxicity that remained after cessation of therapy in 12 patients. Fifteen patients developed other toxicities that were potentially due to CDV or the concomitantly given probenecid. No toxicity was seen in 45 (61.6%) patients. Cidofovir can be considered as second-line therapy in patients with CMV disease failing previous antiviral therapy. However, additional studies are needed before CDV can be recommended for preemptive therapy.     

Successful resolution of bowel obstruction in a patient with hereditary angioedema

Hereditary angioedema (HAE), a rare genetic disorder caused by a deficiency of the C1 esterase inhibitor, leads to an episodic, self-limiting increase in vascular permeability. Related symptoms commonly include recurrent, intractable abdominal pain, vomiting, and/or diarrhea. DX-88 (ecallantide), a 60-amino acid recombinant protein discovered through phage display technology, is a highly specific, potent inhibitor of human plasma kallikrein that has been used successfully in the treatment of patients experiencing acute HAE attacks. This case study involves a 65-year-old woman who presented with severe abdominal pain, cramping, and nausea. The study describes the use of a video obtained by capsule endoscopy for the direct imaging of bowel occlusion in a patient with HAE that resolved upon treatment with DX-88. After administration of DX-88, 80 mg intravenously, abdominal pain and nausea resolved within 30 min. Capsule endoscopy demonstrated a coincident resolution of the bowel wall edema, with a return to normal within approximately 1.5 h of DX-88 administration. This case study demonstrates that DX-88 can produce dramatic clinical benefits in a patient with an acute abdominal HAE attack, resolving both symptoms and pathologic signs. Furthermore, it illustrates the usefulness of videos obtained from capsule endoscopy in identifying the presence of bowel occlusion and demonstrating its subsequent rapid resolution upon administration of DX-88.     

High prevalence of heparin induced thrombocytopenia with thrombosis among patients with essential thrombocytemia carrying V617F mutation

Arterial and venous complications are major causes of morbidity and mortality in myeloproliferative neoplasms (MPNs). MPNs patients, frequently receive heparin. Heparin-induced thrombocytopenia (HIT) is a rare but potentially life-threatening complication resulting in a severe acquired thrombophilic condition. We carried out a retrospective analysis to evaluate occurrence of new thrombotic events during heparin therapy in essential thrombocythemia (ET) patients. We studied 108 ET patients on heparin for treatment of previous thrombotic events or in thromboprophilaxis. Fifty-eight of them carried JAK 2 V617F mutation while 50 patients were without V617F mutation. Ten patients, among those with JAK 2 V617F mutation after a median of 10 days from heparin treatment presented a platelet drop, new thrombotic events and in 10/10 cases heparin-related antibodies were found. In the other group, two patients (4%) presented a platelet drop, thrombotic manifestations and heparin related antibodies. Our data show that HIT is more frequent, during heparin treatment, in patients with ET carrying V617F mutation, as compared with patients without mutations (P?=?0.029). ET with V617F mutation seems to be associated with higher risk of thrombotic complications during heparin treatment. Monitoring platelet counts very closely during the course of heparin is essential especially in ET patients in which platelet drop may be hidden by constitutional thrombocytosis.     

Identification of CD34+ cells in normal and pathological bone marrow biopsies by QBEND10 monoclonal antibody.

Monoclonal antibody QBEND10 is reactive with the CD34 antigen in aldehyde-fixed, decalcified, paraffin-embedded bone marrow biopsies. In normal bone marrow it stained endothelial cells lining arterioles and capillaries, sinusoidal (littoral) cells and 0.89% of all haemopoietic cells. QBEND10+ mononuclear cells were seen as isolated, randomly distributed mononuclear cells in normal and regenerating bone marrows. Conversely, QBEND10+ cells were increased and present in aggregates of three or more cells in 6/8 cases of acute leukemia; in two cases of CD34-negative leukemia and in two patients after complete remission no aggregates were seen. QBEND10 immunohistochemistry may therefore be useful for diagnosis and follow-up of myeloid leukemias. In addition, increased numbers of CD34+ cells arranged in clusters were seen in 4/9 cases of refractory anemia with excess blasts (RAEB), 1 case of chronic myelomonocytic leukemia, 3/3 cases of RAEB in transformation, and in 3/7 cases of chronic myelogenous leukemia: in all these cases, CD34 staining of the bone biopsy may have prognostic value. QBEND10+ endothelial cells were significantly increased in all the pathological conditions examined (1.43% of all nucleated cells versus 0.80% in normal bone marrow; p = 0.0063), but especially in myeloid leukemias and in two fibrotic syndromes examined.     

Hematopoietic stem cell transplantation in adult acute lymphoblastic leukemia: a single-centre analysis

The role of autologous or allogeneic hematopoietic stem cell transplantation (HSCT) in ALL is controversial because of its adverse risk/benefit ratio, and the main policy is to reserve it for high-risk patients. In our Institution, between 1984 and 2002, 40 patients received an allogeneic HSCT and 39 underwent autografting. The conditioning regimen included HD-Ara-C, HD-CTX and 10 Gy fractionated TBI. After allogeneic SCT in first CR, four patients relapsed, leading to a 10-year EFS chance of 78.3%; of the other patients, 5 are still in CR. After autografting in first CR, there was an early death, one secondary AML, one death in CR and six relapses, leading to a 10-year EFS chance of 44.4%; of the other patients, 6 are still in CR. Even considering the limited number of patients and the slow accrual rate, selection bias cannot be considered a sufficient explanation for the favorable outcome of allografting in first CR as the majority of the patients had adverse prognostic factors. It cannot be claimed that allogeneic SCT was performed in patients already cured, as the autografted patients had a notably worse outcome, and a 10-year EFS chance of about 80% is an uncommon finding even in standard-risk ALL patients. It might be inferred that the timing of SCT as late intensification, in addition to a rather aggressive conditioning regimen, helped to minimize the leukemic burden, thus favoring the expression of a GVL effect. Conversely, the results in more advanced disease phases are discouraging, due to poor quality CRs and inefficacy of GVL in managing large residual disease.     

Four-year survival after trans-jugular intrahepatic porto-systemic shunt for veno-occlusive disease following autologous bone marrow transplantation

Severe hepatic veno-occlusive disease is still a potentially lethal complication after bone marrow transplantation. We here report the case of a patient who developed liver veno-occlusive disease with severe hemodynamic dysfunction and was successfully treated by means of a trans-jugular intrahepatic portosystemic shunt. After three years, he is still disease-free with a functioning shunt and a normal laboratory liver profile. A trans-jugular intrahepatic portosystemic shunt is a treatment option that has been used in very few patients affected by hepatic veno-occlusive disease; its indications and timing remain to be established.     

Bone marrow-disseminated tumor cells in patients with carcinoma of the esophagus or cardia

BACKGROUND: The long-term prognosis after surgical therapy for esophageal carcinoma depends on tumor stage and completeness of resection. Similarly to other epithelial tumors, the presence of micro deposits of neoplastic cells in the bone marrow may indicate residual disease and the potential for recurrence. This study assesses the prevalence of bone marrow-disseminated tumor cells in patients undergoing surgical resection for esophageal carcinoma. In addition, we investigated the agreement between immunohistochemical and molecular techniques for the detection of micrometastases in a subgroup of patients. METHODS: Between January 1998 and November 1999, forty-eight patients with adenocarcinoma of the esophagogastric junction (n = 29) or squamous cell carcinoma of the thoracic esophagus (n = 19) and no evidence of overt metastatic disease entered the study. An immunohistochemical assay (capable of detecting 1 carcinoma cell in 7 x 10(5) bone marrow cells) was used to test bone marrow obtained by flushing a resected rib or by needle aspiration either of the iliac crest or of a rib. A polymerase chain reaction (PCR) molecular technique was also used to identify bone marrow and peripheral blood epithelial cells. RESULTS: Cytokeratin-positive cells were found in 79.1% of the bone marrow samples obtained from the rib, and in only 8% of the needle aspirates either from the iliac crest or from a contiguous rib: This difference is probably explained by the improved removal of metastatic cells with the flushing of the rib. Comparable results were obtained at a qualitative level by the PCR technique on bone marrow. In addition, PCR-positive results were found in 3 of 18 peripheral blood samples. There was no association with tumor type, neoadjuvant therapy, or lymph node status. Patients with a pT3 or pT4 tumor showed, at a borderline statistical level, a higher proportion of cytokeratin-positive cells in the flushed rib. CONCLUSIONS: Bone marrow-disseminated tumor cells are present in the resected rib of a high proportion of patients undergoing esophagectomy for carcinoma, and immunohistochemistry seems to be the method of choice for their quantitative assessment. However, the prognostic and therapeutic implications of this finding need further investigation.     

Established and new treatments for hereditary angioedema: An update

Hereditary angioedema (HAE) is due to inherited deficiency of C1-inhibitor (C1-INH) and causes localized swelling that may be life-threatening when it affects the larynx. Replacement therapy with plasma derived C1-INH has been the principal life saving treatment for more than 20 years in several European countries. Nevertheless, it is not licensed in U.S. and even in Europe it is mostly supplied on a named patient basis. In the last 5 years, controlled clinical trials with four products (plasma derived C1-INH, the enzyme inhibitor Dx-88, the receptor antagonist Icatibant and a recombinant form of human C1-INH) have been performed or initiated in order to demonstrate their efficacy in reverting symptoms of HAE. Here we review the characteristics of these products and the current situation of the trials.