Structure-activity relationship studies of novel heteroretinoids: induction of apoptosis in the HL-60 cell line by a novel isoxazole-containing heteroretinoid.

In a search for retinoic acid receptor (RAR and RXR)-selective ligands, a series of isoxazole retinoids was synthesized and evaluated in vitro in transcriptional activation and competition binding assays for RARs and RXRs. In addition, these compounds were evaluated for their differentiating, cytotoxic, and apoptotic activities. In general, these derivatives showed scarcely any binding affinity and were not active in the transcriptional assay. However, among these isoxazole derivatives, the cis-isomer 14b was identified as a potent inducer of apoptosis, and its activity was found to be 6.5 and 4 times superior than that of 13-cis- and 9-cis-retinoic acids, respectively. On the other hand, compound 13b, which has the trans stereochemistry at the double bond, was found not to be active in the apoptotic assay, but it was endowed with appreciable differentiating activity. Therefore, it seems that the different stereochemistry of the double bond may be associated with a different biological activity: potent apoptotic activity for the cis-isomer but differentiating activity for the trans structure. This biological behavior was found, at least in part, for the 9-cis- and 13-cis-retinoic acids with respect to the all-trans-retinoic acid. Thus, structure 14b could offer an interesting model for the design of new compounds endowed with apoptotic activity.

Donor lymphocyte infusions for refractory pure red cell aplasia relapsing after both autologous and nonmyeloablative allogeneic peripheral stem cell transplantation.

Pure red cell aplasia (PRCA) is characterized by a selective marrow aplasia of the erythroid compartment. Immunosuppressive therapy achieves good results in about 25% of cases, but relapses are frequent. Autologous or allogeneic haematopoietic stem cell transplantation (HSCT) may be valuable in selected patients. Here, we report details of a 29-year-old woman treated successfully by donor lymphocyte infusions (DLIs) following allogeneic HSCT for acquired refractory relapsed PRCA. The nonmyeloablative conditioning regimen consisted of cyclophosphamide 60 mg/kg/day for 2 days and fludarabine 30 mg/m(2) daily for 4 days. Haematopoiesis was still completely 'recipient' 1 month after allo-HSCT, but progressed to full donor engraftment after three doses of 'escalating' DLI. The possible role of a graft-versus-autoimmunity effect induced by allogeneic HSCT followed by DLI infusions in the treatment of the disease is discussed.

Crohn's disease complicated by relapsed extranodal Hodgkin's lymphoma: prolonged complete remission after unmanipulated PBPC autotransplant.

Crohn's disease and ulcerative colitis are inflammatory bowel diseases (IBD), which are thought to result from an inappropriate immunologic (autoimmune) response to luminal antibodies. Allogeneic stem cell transplantation (SCT) performed for coincidental diseases is able to cure both leukaemia and Crohn's disease. Autologous SCT is currently performed worldwide for severe autoimmune diseases (SADs) because of its reduced transplant-related mortality (TRM). We report the case of a 30-year-old male patient with a 10-year history of severe Crohn's disease, who developed Hodgkin's disease and received an unmanipulated peripheral blood autologous transplant. Three years after the transplant the patient is in complete treatment-free remission of both diseases.

Successful treatment of resistant thrombotic thrombocytopenic purpura/hemolytic uremic syndrome with autologous peripheral blood stem and progenitor (CD34+) cell transplantation.

The first-line treatment of thrombotic thrombocytopenic purpura-hemolytic uremic syndrome (TTP-HUS syndrome) induces a response and survival rate of approximately 85%, even if a considerable number of patients relapse; nevertheless, a number of these patients are resistant to conventional management. Immunoablation followed by stem cell transplantation has been shown to be capable of inducing remissions in a large spectrum of experimental autoimmune disorders. We report here the case of a 20-year-old male patient with the TTP-HUS syndrome who was resistant to conventional treatment and was transplanted with autologous immunoselected CD34+ PBPC after conditioning with cyclosphosphamide, anti-T lymphocyte globulin and prednisone. Seven months after transplant the patient is alive and well, without any further treatment being given.

Comparative activity of idarubicin and idarubicinol in combination with cyclosporin A in multidrug-resistant leukemia cells.

4-Demethoxydaunorubicin (idarubicin, IDA) is an anthracycline that has shown good cytotoxic activity in vitro against tumor cell lines displaying the multidrug-resistant (MDR) phenotype. IDA is converted in the liver into idarubicinol (2HIDA) and, in this form, seems to exert its antitumoral activity in vivo. Recent studies have shown that 2HIDA has tumoricidal activity similar to that of the parent drug when tested in vitro in sensitive neoplastic cells. In this work we compared in vitro the effects of IDA and 2HIDA used alone and in combination with 2 microM cyclosporin A (CyA) in the MDR leukemic cell lines FLCR and K562R and in their sensitive parent cell lines FLC and K562. IDA and 2HIDA showed the same cytotoxic activity in sensitive cells. After 1 h of exposure of cells to each anthracycline, we observed that the cellular uptake of IDA and 2HIDA was also similar. In resistant cells, 2HIDA was 3-4 times less active than IDA. We observed that the intracellular uptake of 2HIDA was lower than that of IDA, and this may be correlated with a greater ability of P-glycoprotein to expel 2HIDA as opposed to IDA. Indeed, when MDR cells were exposed to IDA and 2HIDA in combination with 2 microM CyA, the cytotoxic effect of these anthracyclines was the same, and it was similar to that observed in sensitive cells. These data confirm the utility of the combination of IDA and an MDR-reversing agent in hematological malignancies displaying the MDR phenotype.

Granulocyte integrins before and after activation in acute ischaemic stroke.

We examined in 19 subjects with acute ischaemic stroke (AIS) the PMN integrin pattern (CD11a, CD11b, CD11c, CD18), using indirect immunofluorescence and adopting a flow cytometer, at baseline and during activation, prolonged for 5 and 15 min, with 4-phorbol 12-myristate 13-acetate (PMA). At baseline, an increase in the expression of CD11c and CD18 and a decrease in the CD11b were evident in AIS subjects compared to normals. After activation, we found in normals a constant and significant increase of all PMN adhesive molecules, while in AIS subjects, we found an increase in CD11b and CD18, a decrease in CD11a and no variation in CD11c. While the basal upregulation of CD11c and CD18 may depend on the PMN spontaneous activation or on the increase of cytokines, the decrease of CD11b may be due to its self-consumption. After activation, the decrease in CD11a noted in AIS may be related to its cleavage or to an altered integrin phosphorylation/dephosphorylation balance.

Polymorphonuclear leukocyte integrin pattern, at baseline and after activation, in type 2 diabetic subjects with macrovascular complications.

In vascular atherosclerotic disease and in diabetes mellitus few studies have evaluated the polymorphonuclear leukocyte (PMN) adhesion molecule pattern. In this study we examined the PMN integrin expression at baseline and after activation in controls and type 2 diabetic subjects with macrovascular complications (MVC). We enrolled 21 subjects with type 2 diabetes mellitus and macrovascular complications, localized in peripheral, coronary and cerebral sites. The patients had peripheral occlusive arterial disease, chronic cerebrovascular disease or coronary heart disease. We evaluated the expression of some PMN integrins (CD11a, CD11b, CD11c, CD18), using flow cytofluorimetry, at baseline and after in vitro activation with 4-phorbol-12-myristate-13 acetate. Type 2 diabetic subjects with MVC showed, compared to normals, an increase of CD11a and CD18 and a decrease of CD11b and CD11c. After activation, in PMN(s) of normal subjects, we found an increase in the expression of all adhesion molecules, while in PMNS of type 2 diabetic subjects with MVC we observed an increase of CD11b and CD11c and a decrease of CD11a. In type 2 diabetic patients with MVC the basal upregulation of CD11a and CD18 may be related to the PMN spontaneous activation, while the behavior of CD11b may depend on its self-consumption. After activation the CD11a modification may be due to its cleavage or to an altered integrin phosphorylation/dephosphorylation balance.

Polymorphonuclear leukocyte integrin profile in diabetes mellitus.

We examined the polymorphonuclear leukocyte (PMN) integrin pattern in 45 diabetic subjects without macrovascular complications, including 21 subjects with type 1 and 24 with type 2 diabetes mellitus. The PMN adhesion molecules (CD11a, CD11b, CD11c, CD18) were evaluated using indirect immunofluorescence and a flow cytometer, at baseline and after in vitro activation with 4-phorbol 12-myristate 13-acetate (PMA) and N-formyl-methionyl-leucyl-phenyl-alanine (fMLP). At baseline, in diabetic subjects the phenotypical expression of CD11a and CD11b was significantly reduced and CD11c was increased, whereas CD18 was unchanged in comparison with normals. Considering type 1 and 2 diabetic subjects separately, CD11a was reduced and CD11c was increased in both subgroups, CD11b was decreased only in type 1 diabetics and CD18, decreased in type 1, was increased in type 2 subjects. After activation with PMA and fMLP, in normal subjects we observed a significant increase of all PMN adhesion molecules whereas in diabetic subjects only CD11c increased significantly with both activating agents, and CD11b increased only after PMA activation. In type 1 diabetic subjects only CD11c expression was increased, and in type 2 diabetic subjects an increase of CD11b (with PMA) and an increase of CD11c (with fMLP) were noted. In conclusion, we found in diabetic subjects of type 1 and 2 an altered behaviour pattern of PMN integrins both at baseline and, in particular, after in vitro activation. These data may help in explaining the role of PMN in the evolution of diabetic vascular complications.

Palonosetron and dexamethasone for prevention of nausea and vomiting in patients receiving high-dose chemotherapy with auto-SCT.

The aim of this study was to determine the efficacy of palonosetron combined with dexamethasone in prevention of chemotherapy (CT)-induced nausea and vomiting (CINV) in patients receiving high-dose (HD)-CT with auto-SCT, and the efficacy of a second dose of palonosetron in treating breakthrough emesis. One hundred thirty-four patients treated with HD-CT and auto-SCT for hematologic malignancies received palonosetron as prophylaxis for CINV on the first day of conditioning; patients were also administered dexamethasone throughout the entire period of conditioning. If breakthrough emesis occurred, a second dose of palonosetron was administered at 72 h after the first administration. Complete response and complete protection were observed in 36 and 26% of patients, respectively. One-half of the patients, re-treated with palonosetron for breakthrough emesis, were successfully rescued. Treatment with palonosetron plus dexamethasone seems to be encouraging in terms of prophylaxis of CINV and treatment of breakthrough emesis in the setting of HD-CT.

Autologous peripheral blood stem and progenitor (CD34+) cell transplantation for systemic lupus erythematosus complicated by Evans syndrome.

Immunoablation followed by allogeneic stem cell (SC) transplantation has been shown to be capable of curing a large spectrum of experimental autoimmune disorders, hereditary and/or induced. Superimposable results, albeit with some exceptions, have been obtained in human patients affected by coincidental autoimmune and blood diseases. However, both because of encouragine experimental results and of the procedure's greater safety, autologous SC are being increasingly utilized worldwide. Case reports are being collected in the registry of the European Group for Blood and Marrow Transplantation (EBMT)/European League against Rheumatism (EULAR) Autoimmune Disease Stem Cell Project. Among the severe autoimmune diseases (SADs), which are the target of autologous transplantation, severe refractory systemic lupus erythematosus (SLE) is a condition which may benefit from this procedure. We report here the case of a 19 year old female patient with a six year history of SLE with secondary antiphospholipid syndrome (APS), who later developed refractory Evans syndrome. She was transplanted with autologous mobilized CD34+ SC and progenitor cells after conditioning with cyclosphosphamide, anti-T lymphocyte globulin and prednisone. Eight months after transplant, the patient is alive and well, with normal blood counts and persistent low-titre direct antiglobulin (DAT, Coombs) and anti-nuclear antibody (ANA) tests. Anti-double stranded DNA antibody (Anti-dsDNA), lupus anticoagulant tests and anti-cardiolipin antibody (ACA) test are negative.

Intense immunosuppressive therapy followed by autologous peripheral blood selected progenitor cell reinfusion for severe autoimmune disease.

Autologous stem cell transplantation (HSCT) has been shown to be effective in curing a large spectrum of autoimmune disorders. Case reports are being collected in the EBMT/EULAR Autoimmune Disease Stem Cell Project registry, which reports transplant-related mortality (TRM) of 6%. In order to reduce TRM and preserve the anti-autoimmune effect we evaluated a more immunoablative as opposed to myeloablative conditioning regimen for the autotransplant of severe immunomediated diseases. We enrolled patients affected by systemic lupus erythematosus (SLE: 3 patients), by autoimmune thrombocytopenic purpura (AITP: one patient), by thrombotic thrombocytopenic purpura (TTP: one patient), by pure red cell aplasia (PRCA: one patient), and by a severe cryoglobulinemia (one patient). All patients were mobilized with cyclophosphamide (Cy) 4 g/m2 + G-csf. Conditioning regimen consisted of Cy 50 mg/kg/day (days -6 and -5); anti-T-globulin (ATG) 10 mg/kg/day and 6-methylprednisolone (PDN) 1 g/day (days -4, -3, and -2). Immunomagnetically selected CD34+ cells were re-infused on day 0. In three patients neutrophil count fell below 0.5 x 10(9)/l, while a PLT count below 20 x 10(9)/l was registered in two patients. Extrahematological toxicity was very low. Four patients (2 SLE, 1 TTP, 1 cryoglobulinemia) are in complete corticosteroid-free remission with a median follow up of 335 days. The third SLE patient improved considerably; however, he still needs low-dose corticosteroid maintenance. The AITP and PRCA patients achieved a CR but soon relapsed; nevertheless, the procedure restored a steroid-sensitive status. The use of this immunoablative conditioning regimen in auto-HSCT transplant was shown to be effective in controlling disease progression and could be a valuable strategy in reducing TRM.

Polymorphonuclear integrins, membrane fluidity, and cytosolic Ca(2+) content after activation in essential hypertension.

The purpose of this research was to obtain further information about the role of polymorphonuclear leukocytes in essential hypertension. These cells could be involved in the pathogenesis of organ injury. Thirty subjects (14 men and 16 women) with essential hypertension were enrolled. In these subjects we determined, at baseline and after in vitro activation with 4-phorbol 12-myristate 13-acetate and N:-formyl-methionyl-leucyl-phenylalanine, the polymorphonuclear leukocyte membrane fluidity, obtained by labeling the cells with 1-[4-(trimethylamino)phenyl]-6-phenyl-1,3, 5-hexatriene, cytosolic Ca(2+) concentration, obtained by marking the cells with Fura 2-AM, and integrin pattern (CD11a, CD11b, CD11c, and CD18), by using the indirect immunofluorescence with a flow cytometer. At baseline there was no difference in membrane fluidity between normal subjects and hypertensives, whereas hypertensives showed an increase in cytosolic Ca(2+) content and an increase of the phenotypical expression of CD11a, CD11b, and CD18. In normal subjects and in hypertensives, after activation, no variation was found in membrane fluidity and cytosolic Ca(2+) content. In normal subjects, after activation, we observed a significant increase of the expression of all adhesion molecules, whereas in hypertensives we found an increase of the expression of CD11b, CD11c, and CD18 but also a decrease of CD11a. The behavior of the polymorphonuclear leukocyte integrin profile may have several explanations, and in particular, the trend of CD11a after chemotactic activation may be related to its cleavage or to an altered integrin phosphorylation/dephosphorylation balance hypothetically present in this clinical condition.

Low-dose long-term oral idarubicin in maintenance treatment of elderly acute myeloid leukemia.

BACKGROUND AND OBJECTIVE: Low-dose long-term oral IDA may play a role in maintainance treatment of elderly patients with AML; in fact, continuous exposure to IDA and IDAol could be efficacious in the disease control possibly inducing cell-differentiation and/or apoptosis. METHODS: We enrolled 25 previous responder patients in standard induction therapy to receive maintenance oral IDA 5 mg daily on days 1-14 at 2-week intervals for at least 6 months. We also evaluated the cell-cycle and apoptosis in leukemic cells from patients after IDA administration and, as a control, from HL60 lines exposed to IDA and IDAol in vitro. RESULTS: Long-term long-dose IDA was well-tolerated. Neutrophil and platelet count never below under 1 x 10(9)/L and 50 x 10(9)/L respectively in CR patients, and no infectious complications were encountered. Non-hematological toxicity was also acceptable: easily controlled nausea and vomiting, non-recorded diarrhea or mucositis were reported. The convenience of oral administration contributed to excellent compliance. DNA analysis performed in vivo after IDA and IDAol exposure showed an increase of G2/M cell frequencies and evidence of sub-G1 peak. INTERPRETATION AND CONCLUSIONS: In conclusion, long-term low doses of oral IDA would appear valuable as a maintenance regimen for elderly patients. Our results seem to confirm the preliminary hypothesis that IDA + IDAol induce an increase of apoptosis in leukemic cells.

Effects of R-enantiomer (GR66234A) and L-enantiomer (GR66235A) of telupidine, a new dihydropyridine derivative, on cell lines displaying the multidrug resistant phenotype.

BACKGROUND: Many dihydropyridine analogues with calcium channel blocker activity are able to reverse multidrug resistance (MDR). We studied the daunorubicin resistance reversing activity of the R enantiomer (GR66234A) and the L-enantiomer (GR66235 A) of teludipine, a new lipophilic calcium channel blocker synthesized by Glaxo. METHODS: The daunorubicin resistance reversing activity of the enantiomers of teludipine was evaluated in two MDR cell lines: ARNII, an erythroleukemia cell line which expresses p-glycoprotein, and MCF 7/R, a breast cancer cell line with p-glycoprotein and high levels of glutathione S transferase (GST) and glutathione peroxidase (GSH Px). RESULTS: GR66234A and GR66235A show the same activity in reversing daunorubicin resistance and are more effective than verapamil. The difference in activity between verapamil and the enantiomers of teludipine is greater in ARNII cells than in MCF 7/R cells. Nevertheless, there are no significative differences in cellular daunorubicin accumulation between ARNII and MCF 7/R following exposure to teludipine, nor are there differences in intracellular daunorubicin distribution in the presence of either MDR reversing agent. CONCLUSIONS: The low calcium channel antagonistic activity of GR66234A suggests that this compound may be useful in combination with chemotherapy in MDR malignancies.