The dual specificity phosphatase PTEN exerts its tumour suppressor and cell-migration regulatory functions by dephosphorylating the phospholipid substrate, phosphatidylinositol-3,4,5-trisphosphate (PI(3,4,5)P(3)), and phosphotyrosine protein substrates. PTEN functions are regulated by phospholipid binding, interactions with other cellular proteins and phosphorylation at multiple sites. Precisely, how the phosphorylation and binding events modulate PTEN activity and structure remains mostly unclear.
View Article and Find Full Text PDFPTEN exerts its tumour suppressor function by dephosphorylating the phospholipid second messenger phosphatidylinositol-3,4,5-trisphosphate (PIP(3)). Herein, we demonstrate that the PTEN-catalysed PIP(3) dephosphorylation reaction involves two-steps: (i) formation of a phosphoenzyme intermediate (PE) in which Cys-124 in the active site is thiophosphorylated, and (ii) hydrolysis of PE. For protein tyrosine- and dual-specificity phosphatases, catalysis requires the participation of a conserved active site aspartate as the general acid in Step 1.
View Article and Find Full Text PDFOveractive bladder (OAB) is a highly prevalent symptom syndrome that negatively affects health-related quality of life (HRQL). In clinical practice, the diagnosis and treatment of OAB are largely driven by a patient's reporting of symptoms, often in combination with objective assessment. Thus, OAB provides the opportunity to examine the relations between objective (eg, urodynamic studies, bladder diary variables) and subjective (eg, symptom bother, HRQL) outcomes.
View Article and Find Full Text PDFObjective: To develop the first Canadian guidelines for the management of adult urinary incontinence (UI).
Method: Following a mandate of the Canadian Urological Association, six Canadian urologists collaborated to produce these guidelines after having extensively reviewed existing foreign guidelines and literature from 1966 to June 2005.
Results: The terminology proposed by the standardization committee of the International Continence Society (ICS) is recommended.
We explored the safety and efficacy of rituximab administered in combination with the standard transplant conditioning regimen of cyclophosphamide (Cy) 120 mg/kg and total body irradiation (TBI) 12 Gy for adult patients with acute lymphoblastic leukemia (ALL). Patients were eligible if their disease expressed CD20. Rituximab was administered at 375 mg/m2 weekly for four doses beginning on day -7 of the conditioning regimen.
View Article and Find Full Text PDFThe role of high-dose chemotherapy (HDCT) in patients with refractory breast cancer is not well established. Forty-two female patients (median age of 46 years) with breast cancer refractory to neoadjuvant chemotherapy received HDCT (cyclophosphamide, carmustine and thiotepa) supported by an autologous peripheral blood stem cells transplant. Their disease had been refractory (defined as less than partial response) to one (18 patients) or two (24 patients) regimens of neoadjuvant chemotherapy.
View Article and Find Full Text PDFBiol Blood Marrow Transplant
December 2005
Reports have shown a worse outcome for donor-recipient pairs mismatched for ABO blood groups in bone marrow transplantation (BMT). These studies, however, included small and heterogeneous study populations, and not all considered bidirectional ABO incompatibility separately. Because the issue remains controversial, we analyzed the effect of ABO mismatch on the overall survival, transplant-related mortality, and occurrence of acute and chronic graft-versus-host disease (GVHD) in a large homogenous group of patients undergoing allogeneic BMT.
View Article and Find Full Text PDFTo address deficiencies in Current Procedural Terminology (CPT) codes that describe many of the clinical services offered to patients, several physicians in the blood and marrow transplantation and apheresis field joined with a coalition including the American Society of Hematology, American Society for Blood and Marrow Transplantation, American Association of Blood Banks, American Society of Clinical Oncology, American Society for Apheresis, National Marrow Donor Program, and American Red Cross to collaborate in addressing these deficiencies by designing new CPT codes. The CPT editorial panel approved 18 new or revised codes. All these codes were given permanent or temporary value by the relative value unit update committee, but not all values were approved by the Centers for Medicare & Medicaid Services (CMS), in particular, the cell-processing codes and the unrelated donor search code.
View Article and Find Full Text PDFObjectives: To compare, in a multicenter, randomized clinical trial, collagen injections versus surgery with regard to efficacy, quality of life, satisfaction, and complications.
Methods: Of 133 women with stress urinary incontinence, 66 were randomized to collagen injection and 67 to surgery (6 needle bladder neck suspensions, 19 Burch, and 29 slings). After randomization, 15 women refused their allocated treatment.
Allogeneic progenitor cell transplantation is the only curative therapy for patients with refractory acute myelogenous leukemia or myelodysplastic syndromes. To identify prognostic factors in these patients, we performed a retrospective analysis of transplantation outcomes. Patients were selected if they had undergone an allogeneic transplantation between January 1988 and January 2002 and were not in remission or first untreated relapse at the time of transplantation.
View Article and Find Full Text PDFWe assessed the 5-year results of a high-dose cyclophosphamide, carmustine, and thiotepa (CBT) regimen plus autologous hematopoietic stem cell transplantation (AHST) as an adjuvant consolidation therapy for high-risk primary breast cancer patients with > or =10 positive axillary lymph nodes after primary surgery or > or =4 positive axillary lymph nodes after neoadjuvant chemotherapy and surgery. The associations of various potential prognostic factors with the relapse-free survival (RFS) rate and overall survival (OS) rate were determined. Between October 1992 and March 2000, 177 eligible patients (median age, 46 years) were given high-dose CBT followed by AHST.
View Article and Find Full Text PDFBiol Blood Marrow Transplant
July 2004
The high cost per patient of hematopoietic cell transplantation (HCT) causes this therapy to be the focus of much controversy, given the competing societal demands to provide all possible therapy to preserve life while simultaneously limiting global health care expenditures. Treatment and eligibility decisions for HCT often are heavily scrutinized by both governmental and private payers and not simply determined by physicians, facility providers, and the patient. In an effort to control costs, payers have administrative infrastructure to review resource utilization by these patients.
View Article and Find Full Text PDFPrevious work suggested that interleukin (IL)-2 can be used for eradicating residual disease in autologous grafts and for preventing recurrence. We report a phase II study of autologous peripheral blood stem cell transplantation with in vitro IL-2 incubation of peripheral blood stem cells and posttransplantation IL-2 in patients with recurrent or refractory non-Hodgkin lymphoma. Salvage chemotherapy consisted of ifosfamide and etoposide.
View Article and Find Full Text PDFThe purpose of this study was to identify characteristics significant to survival and progression-free survival in patients with advanced ovarian cancer receiving high-dose chemotherapy. In all, 96 patients received autologous stem cell transplantation. Regimens included paclitaxel with carboplatin (PC), topotecan, melphalan, cyclophosphamide (TMC) and cyclophosphamide, BCNU, thiotepa (CBT).
View Article and Find Full Text PDFIntensity of the preparative regimen is an important component of allogeneic transplantations for myelodysplasia (MDS) or acute myelogenous leukemia (AML). We compared outcomes after a truly nonablative regimen (120 mg/m2 fludarabine, 4 g/m2 cytarabine, and 36 mg/m2 idarubicin [FAI]) and a more myelosuppressive, reduced-intensity regimen (100 to 150 mg/m2 fludarabine and 140 or 180 mg/m2 melphalan [FM]). We performed a retrospective analysis of 94 patients with MDS (n = 26) and AML (n = 68) treated with FM (n = 62) and FAI (n = 32).
View Article and Find Full Text PDFDespite posttransplantation immunosuppressive therapy, acute graft-versus-host disease (GVHD) remains a major cause of sickness and death. Tumor necrosis factor-alpha (TNF-alpha) is implicated in the pathophysiology of GVHD at several steps in the process. Infliximab is a genetically constructed immunoglobulin G1 (IgG1) murine-human chimeric monoclonal antibody that binds the soluble subunit and the membrane-bound precursor of TNF-alpha, blocking its interaction with receptors and causing lysis of cells that produce TNF-alpha.
View Article and Find Full Text PDFOur purpose was to study the risk factors associated with disease progression after high-dose chemotherapy followed by autologous stem cell transplantation in patients with recurrent or refractory Hodgkin's lymphoma (HL). We analyzed the long-term outcome of 184 patients with recurrent or refractory HL who underwent autologous hematopoietic stem cell transplantation. At the time of transplantation, 82 patients were in first relapse or second remission, 46 patients were refractory to the primary induction chemotherapy, and 56 patients were beyond first relapse or second remission.
View Article and Find Full Text PDFIn this study, we evaluated the influence of nonmyeloablative and ablative conditioning regimens on the occurrence of acute and chronic graft-versus-host disease (GVHD). One hundred thirty-seven patients undergoing matched-related sibling transplantations received the same GVHD prophylaxis. Myeloablative regimens included intravenous busulfan/cyclophosphamide (n=45) and fludarabine/melphalan (n=29).
View Article and Find Full Text PDFWe evaluated the feasibility and efficacy of a reduced-intensity conditioning (RIC) regimen of fludarabine and melphalan to achieve rapid complete donor chimerism after allogeneic stem cell transplantation (SCT) in patients with metastatic solid tumors. Between January 1999 and January 2003, 8 patients with metastatic breast cancer (BC) and 15 with metastatic renal cell carcinoma (RCC) underwent allogeneic SCT after an RIC regimen of 5 days of fludarabine and 2 days of melphalan. Filgrastim-mobilized stem cells from HLA-identical related or unrelated donors were infused.
View Article and Find Full Text PDFHematopoietic stem cell transplantation from unrelated donors is an effective treatment for myeloid malignancies, but its use is usually restricted to young patients without comorbidities. The development of reduced-intensity preparative regimens has allowed the extension of this form of treatment to older and medically infirm patients. We assessed the outcomes of patients older than 54 years who received unrelated donor transplants for the treatment of myeloid malignancies in our institution.
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