Influence of thalidomide on Bcl2 expression and proangiogenic cytokine levels in short-term culture of peripheral blood and bone marrow mononuclear cells of multiple myeloma patients.

Supernatants from short-term culture of peripheral blood and bone marrow mononuclear cells obtained from 22 multiple myeloma patients were used to measure the concentration of TNF-alpha, HGF, IL-6 and its soluble receptor (sIL-6R), VEGF and bFGF. Cells were cultured with or without thalidomide (THAL). We observed statistically significant decrease in TNF-alpha, HGF, IL-6, sIL-6R in supernatants from THAL cultures compared to cells cultured without THAL. Flow cytometry technique was applied to study the Bcl2 expression on CD 4, CD 8 and CD 138 positive cells. The statistically significant decrease in Bcl2 expression on myeloma cells (CD 138+) was observed both in PB and BM cultures. THAL could inhibit the plasma cell growth both by diminishing proangiogenic cytokines production and enhancing myeloma cell apoptosis.

Rituximab (Mabthera, Rituxan) in patients with recurrent indolent lymphoma: evaluation of safety and efficacy in a multicenter study.

The objective of this multiinstitutional study was to evaluate the safety and efficacy of rituximab at standard four weekly doses in patients with recurrent indolent lymphoma. Thirty-eight patients entered into this study, 63% had follicular lymphoma and 61% had an IPI score of 2 or more. Median disease duration was 3 yr, median number of prior treatments was three, and 66% of patients responded to the immediate past treatment with a median remission duration of 3 mo. A total of 158 antibody doses were given, including two patients who received two courses of four infusions each. One patient developed acute respiratory failure after the second dose and required assisted ventilation. There was no immediate relationship to the antibody infusion and no evidence of infection. This complication resolved and the patient successfully completed the full course of the antibody treatment. Another patient discontinued therapy after the second dose owing to intolerable fever and painful erythema. Sixty percent of the first, and 20% of subsequent rituximab infusions were associated with infusion-related reactions including mild fever, chills, and occasional skin eruptions. Complete and partial responses were achieved in 24% and 35% of 34 evaluable patients, respectively, for an overall response rate of 59%. The median time to progression/relapse in responding patients was 16 mo (95% CI, 6.4, 25.6) compared with a median of 3 mo duration of response to the immediate previous therapy in these patients. Longer response duration post rituximab monotherapy than with previous treatment in this series of heavily pretreated patients suggests a major role for the antibody in the therapy of patients with indolent lymphoma.

Short Communication: Expression of Apoptosis Regulating Factors on T Lymphocytes in Multiple Myeloma Patients.

Multiple myeloma (MM) is a malignant proliferation of plasma cells in which dysregulation of programmed cell death (apoptosis) is responsible for tumor cell expansion. However some phenotypic and functional alterations of T cells in MM patients have been reported, that also can influence the plasma cell growth. The aim of the study was to assess some aspects of T lymphocyte apoptosis in MM to obtain a better understanding of the changes in the immune system in this disease. Flow cytometry was used to analyze the expression of two main regulators of apoptosis: the pro-apoptotic Fas antigen and the anti-apoptotic protein BCL-2 in patients with untreated MM and in healthy controls. ELISA was used to determine soluble Fas ligand (sFasL) serum levels in patients and control groups. We detected statistically significant higher Fas expression in patients than in controls both on CD4 and CD8 lymphocytes, but no differences in BCL-2 expression by these cells. The sFasL level was statistically significant lower in patients than in controls. Our results indicate that T cells in MM are controlled by up-regulation of Fas. The Fas/FasL system induces the killing of T cells expressing Fas antigen, what could account for the incapability of the immune system to protect host against tumor expansion.

Assessment of Apoptosis Regulating Factors BCL-2 and Fas Antigens on Malignant and Normal Plasma Cells.

Multiple myeloma (MM) is characterised by slow proliferation of malignant plasma cells and their accumulation within the bone marrow. The dysregulation of programmed cell death (apoptosis) is a very important mechanism in the pathogenesis of this tumour. It prompted us to investigate the apoptosis regulating factors such as the pro-apoptotic Fas antigen and the anti-apoptotic protein BCL-2 on bone marrow malignant plasma cells in untreated patients with newly diagnosed MM and to compare them with their normal counterparts-plasma cells isolated from bone marrow of healthy individuals. Twenty-nine MM patients and 16 healthy persons were studied. Bone marrow mononuclear cells were isolated, indicated by monoclonal antibodies and analysed using the flow cytometry method. There was no statistically significant difference in BCL-2 expression in plasma cells between patients and control groups. However the percentage of BCL-2 positive cells was significantly related to the clinical stage of the disease. We detected statistically significant lower percentage of Fas positive cells in the patient group than in control. We concluded that in MM at diagnosis the expression of BCL-2 in bone marrow malignant plasma cells was comparable to normal plasma cells but expression of Fas antigen on these cells was lower. It suggests that down regulation of Fas and normal regulation of BCL-2 may be implicated for myeloma cell survival and their escape from apoptosis in vivo.

[The influence of verapamil on platelet function in patients with multiple myeloma]. / Wplyw werapamilu na czynnosc krwinek plytkowych u chorych na szpiczaka plazmocytowego.

Influence of verapamil on platelet function was evaluated in 7 female and 8 male patients with myeloma. The inhibitory effect on platelet aggregation and other parameters was documented in clinical observation.

[Expression of platelet activation markers--selectin P and glycoprotein CD63 during hemodialysis]. / Ekspresja markerów aktywacji plytek krwi--selektyny p oraz glikoproteiny CD63 w czasie hemodializy.

The bleeding tendency is a common feature of chronic uremia. Abnormalities of platelet function play a role in the pathogenesis of this disorder. A direct contact between platelets and an artificial dialysis membrane results in strong activation of thrombolysis. The aim of our study was to investigate platelets activation in vivo during haemodialysis. We used monoclonal antibodies specific against platelet activation markers--selectin P (CD62) and glycoprotein CD63. The expression of those antigens was analyzed by flow cytometry. Blood samples were obtained from 20 long-term haemodialysed patients with end-stage renal disease. After 15 minutes of haemodialysis the expression of CD62 and CD63 was significantly higher (p < 0.001) as compared CD63 glycoprotein. Our results show that haemodialysis has a significant influence on platelet activation and can favour co-existence of the bleeding tendency and the prothrombotic status in long-term hemodialyzed patients.

Influence of indobufen on occlusion of arteriovenous fistulas and some platelet activity in intermittent peritoneal dialysis patients.

Thrombotic complications constitute a significant problem connected with maintaining arteriovenous fistulas (A-V) for a long time. It has been established that platelets play an important role in the development of thrombosis in high flow systems. Aspirin and dipyridamole do not decrease the frequency of shunt thrombosis. Some of the more recently synthetised antiplatelet drugs (i.e. indobufen, 2-p-oxo-isoindolinyl-phenyl-butyric acid) could be promising in the prevention of such complications. The study group consisted of 40 patients in the terminal stage of renal failure treated with intermittent peritoneal dialysis (IPD). The A-V fistulas were formed by the same surgeon anesthetist team and this allowed for the elimination of technical errors. All patients were divided into two groups. Group I received indobufen at the dose of 2 x 100 mg/24 h orally. Group II received no antiplatelet treatment. The therapy started 24 h before A-V formation. The treatment was continued for 3 weeks. The following tests of platelet function were performed before indobufen therapy, after 9 h and 3 weeks of treatment: ADP and adrenaline induced platelet aggregation, platelet circulating aggregates, MDA level, platelet factor 3 and 4 and bleeding time. During indobufen treatment only a significant decrease in ADP induced aggregation was observed. No prolongation of the bleeding time was noted. No case of fistula thrombosis in indobufen group was observed. This complication, however, appeared in 3 patients (15%) of the control group (without antiplatelet therapy).

Indobufen induced modification of phospholipid composition in diabetic platelets.

The influence of indobufen (200 mg twice daily for 10 days) on platelet lipid peroxidation and phospholipid metabolism in diabetic patients was investigated. We have studied 18 patients with type I of diabetes mellitus. The duration of disease varied between 3 and 25 years (average 11 years). All patients showed symptoms of diabetic angiopathy. Investigations were carried out after restoring the carbohydrate balance. The following tests were performed before and after a 10 day treatment with indobufen: malondialdehyde, conjugated dienes and lipid hydroperoxides, phospholipids, fatty acids. We observed a significantly higher production of lipid peroxidation products in diabetic platelets compared to control platelets. After a 10 day treatment with indobufen the intensity of peroxidation lowered significantly. The phospholipid composition of diabetic platelets showed a significant increase in lysophosphoglycerides fraction compared to the control platelets. After the indobufen treatment a significant decrease in sphingomyelin content was observed. In other phospholipid fractions no significant differences were observed.

Lipid peroxidation products and changes in phospholipid composition induced by indobufen in diabetic platelets.

Indobufen is an antiaggregatory drug which first of all inhibits platelet aggregation by interfering with cyclooxygenase enzymes in platelets. We have investigated the influence of indobufen (200 mg twice daily for 10 days) on platelet lipid peroxidation and phospholipid metabolism in diabetic patients. The production of lipid peroxidation products was significantly lower after drug treatment. Indobufen administration, however, had no influence on the fatty acid composition of platelet phospholipids.

[The effect of indobufen on platelet function and dialyzer regeneration in patients on hemodialysis]. / Wplyw indobufenu na czynnosc krwinek plytkowych i regeneracje dializatorów u chorych hemodializowanych.

In 16 patients on chronic haemodialysis treatment the platelet activation and function were studied during 2 weeks antiplatelet therapy with indobufen. Followings tests were made: platelet count, platelet aggregation, platelet factor 3 and 4. Indobufen inhibited platelet function, mainly release of platelet factor 4 and improved dialyser regeneration.