Signaling Events During Induction of Plasminogen Activator Inhibitor-1 Expression by Sphingosylphosphorylcholine in Cultured Human Dermal Fibroblasts

Sphingosylphosphorylcholine (SPC) is a bioactive sphingolipid metabolite that can enhance wound healing. In a search for effectors downstream of SPC in the wound-healing process, we found that the expression of the gene for plasminogen activator inhibitor-1 (PAI-1) was significantly affected. ELISA and western blot analyses showed that SPC markedly induced PAI-1 production in human dermal fibroblasts cultured in vitro. Inhibition by pre-treatment with pertussis toxin (PTx), but not by tyrphostin A47 (a receptor tyrosine kinase inhibitor), indicated that PTx-sensitive G proteins were involved in SPC-induced PAI-1 expression. SPC elicited a rapid and transient increase in intracellular calcium levels ([Ca2+]i), measured using laser scanning confocal microscopy, which was partly mediated through PTx-sensitive G proteins. Pre-treatment with thapsigargin, but not with EGTA, abolished SPC-induced PAI-1 expression, indicating the importance of Ca2+ release from internal stores. Phorbol-12-myristate-13-acetate (PMA) induced the expression of PAI-1, and pre-treatment with Ro 31-8220 (a PKC inhibitor) markedly suppressed SPC-induced PAI-1 expression. SPC-induced PAI-1 expression was also significantly suppressed by PD98059 (a specific MAPK kinase 1/2 inhibitor). Consistent with this result, SPC stimulated the phosphorylation of p42/44 extracellular signal-regulated kinase (ERK). Together, these results suggest that SPC induces PAI-1 production through a G protein-coupled calcium increase and downstream kinase signaling events in cultured human dermal fibroblasts

Polymorphisms in Genes That Regulate Cyclosporine Metabolism Affect Cyclosporine Blood Levels and Clinical Outcomes in Patients Who Receive Allogeneic Hematopoietic Stem Cell Transplantation

In patients who received allogeneic hematopoietic stem cell transplantation (HSCT), we investigated the correlations between single nucleotide polymorphisms (SNPs) in genes that regulate cyclosporine metabolism and clinical outcomes. All patients received sibling-matched HSCT. DNA samples of patients and donors were analyzed for 4 SNPs: MDR1 +1236C>T (rs1128503), +2677G>T>A (rs2032582), +3435C>T (rs1045642), and CYP3A5 +6986G>A (rs776746). A total of 156 patients (median age 40 years) were analyzed. Nineteen patients received HSCT for nonmalignant disease. The CYP3A5 +6986AA genotype was associated with a high cyclosporine blood level after transplantation. However, this genotype was not related to any particular clinical outcome. In contrast, the MDR1 +1236C>T SNP was correlated with specific clinical outcomes. When neither the donor nor the recipient had the CC genotype of MDR1 +1236, patients had lower creatinine levels (P < .001) and less transplantation-related mortality (TRM) (P = .012). These patients also showed longer overall survival (OS) in both univariate (P = .003) and multivariate (P = .003) analyses. Although the CYP3A5 +6986AA genotype was correlated with a high blood cyclosporine concentration, lack of the MDR1 +1236CC genotype in both the donor and recipient was correlated with less TRM and a longer OS in patients who received allogeneic HSCT

High dose therapy followed by autologous peripheral blood stem cell transplantation as a first line treatment for multiple myeloma: a Korean Multicenter Study.

We conducted a phase II multicenter trial to estimate the response and survival of patients with newly diagnosed multiple myeloma to high dose melphalan therapy followed by autologous peripheral blood stem cell transplantation. Eligible patients who had undergone induction with vincristine, adriamycin and dexamethasone (VAD) should have adequate cardiac, pulmonary and renal function (creatinine <2 mg/dL). Melphalan at 200 mg/m2 was used as a conditioning regimen. Eighty patients were enrolled from 13 centers. The median age of the patients was 53 yr (range; 20 to 68 yr). The initial stage was IA/IIA/IIB/IIIA/IIIB in 3/8/1/54/14 patients, respectively. Beta2-microglobulin, CRP and LDH were increased in 74, 42 and 34% of the patients examined. Cytogenetic data were available in 30 patients, and 6 patients showed numeric or structural abnormalities. Two therapy-related mortalities occurred from infection. Among the 78 evaluable patients, CR/PR/MR/NC/PD were achieved in 48/26/2/1/1 patients, respectively. After a median follow-up of 30 months, the median overall and event-free survivals were 66 months (95% CI: 20-112) and 24 months (95% CI: 18-29), respectively. This study verifies the efficacy and feasibility of high dose melphalan therapy with autologous stem cell transplantation in newly diagnosed multiple myeloma

Hematopoietic Stem Cell Transplantation after Posttransplant Lymphoproliferative Disorder

A 16-yr-old girl received liver transplantation for fulminant hepatitis. Aplastic anemia developed, and she received hematopoietic stem cell transplantation (HSCT). Eleven months after liver transplantation, abdominal lymph node enlargement and colon ulcers were observed, and colon biopsy showed posttransplant lymphoproliferative disorder (PTLD). Immunosuppression reduction was attempted, but it produced no therapeutic effect. Fourteen months after liver transplantation, she received a second HSCT due to engraftment failure, and PTLD resolved completely. The second HSCT can serve as cellular therapy for PTLD

Human AQP5 Plays a Role in the Progression of Chronic Myelogenous Leukemia (CML)

Aquaporins (AQPs) have previously been associated with increased expression in solid tumors. However, its expression in hematologic malignancies including CML has not been described yet. Here, we report the expression of AQP5 in CML cells by RT-PCR and immunohistochemistry. While normal bone marrow biopsy samples (n = 5) showed no expression of AQP5, 32% of CML patient samples (n = 41) demonstrated AQP5 expression. In addition, AQP5 expression level increased with the emergence of imatinib mesylate resistance in paired samples (p = 0.047). We have found that the overexpression of AQP5 in K562 cells resulted in increased cell proliferation. In addition, small interfering RNA (siRNA) targeting AQP5 reduced the cell proliferation rate in both K562 and LAMA84 CML cells. Moreover, by immunoblotting and flow cytometry, we show that phosphorylation of BCR-ABL1 is increased in AQP5-overexpressing CML cells and decreased in AQP5 siRNA-treated CML cells. Interestingly, caspase9 activity increased in AQP5 siRNA-treated cells. Finally, FISH showed no evidence of AQP5 gene amplification in CML from bone marrow. In summary, we report for the first time that AQP5 is overexpressed in CML cells and plays a role in promoting cell proliferation and inhibiting apoptosis. Furthermore, our findings may provide the basis for a novel CML therapy targeting AQP5

Perioperative Anticoagulation in Patients with Mechanical Heart Valves Undergoing Elective Surgery: Results of a Survey Conducted among Korean Physicians

The optimal perioperative anticoagulation management in patients on warfarin therapy is poorly defined due to the lack of randomized trials. Because guidelines are heterogeneous, it was hypothesized that "treatment strategies are not uniform in clinical practice". Between February 2003 and May 2003, a questionnaire with 4 different clinical scenarios was distributed to physicians by e-mail, or direct contact was made by a survey monitor. Two scenarios described the cases of patients with a mechanical heart valve (MHV) in the mitral position, with additional risk factors for a systemic embolism; one undergoing major (scenario 1) and the other minor surgery (scenario 3). Two scenarios described patients with an aortic MHV; one undergoing major (scenario 2) and the other minor (scenario 4) surgery. Different preoperative and postoperative management options were offered. The treatment options for all scenarios were the same. Of the 90 questionnaires distributed, 52 (57.8%) were returned. Hospitalization for full-dose intravenous unfractionated heparin (IV UH) was the most commonly selected strategy in the preoperative phase for scenarios 1 (59%), 2 (42%) and 3 (44%). In scenario 4, 34% chose IV UH. Outpatient, full-dose, subcutaneous UH or low-molecular-weight heparin (LMWH) was the most selected option in the postoperative phase for all scenarios, with the exception of number 4 (52.9% in scenario 1, 34% in scenario 2, 32%, in scenario 3 and 28% in scenario 4). Even among expert clinicians, the management of perioperative anticoagulation is heterogeneous. In particular, the definition of risk categories and the optimal intensity of antithrombotic drugs need to be defined by well-designed prospective studies

Pneumatosis Intestinalis with Pneumoperitoneum Mimicking Intestinal Perforation in a Patient with Myelodysplastic Syndrome after Hematopoietic Stem Cell Transplantation

Pneumatosis intestinalis (PI) is an uncommon disorder characterized by an accumulation of gas in the bowel wall, and has been associated with a variety of disorders and procedures. We describe a 35-year-old man who undertook hematopoietic stem cell transplantation due to myelodysplastic syndrome. An abdominal X-ray demonstrated extensive PI with pneumoperitoneum mimicking hollow organ perforation. However, the patient had no abdominal symptoms and there was no evidence of peritoneal inflammation. After two weeks of conservative management, including bowel rest and antibiotics, his pneumoperitoneum resolved spontaneously without any complications. Of the many factors that affect the gastrointestinal tract mucosal integrity, intramural pressure, and bacterial flora-produced intraluminal gas interact to produce PI. If the condition is accompanied by bowel ischemia, portomesenteric venous gas, metabolic acidosis, and abdominal sepsis, or if PI is severe in extent immediate surgical intervention is indicated. The described case supports that a mechanical rather than a bacterial etiology underlies the pathogenesis of PI