Cell cycle phase perturbations and apoptosis in tumour cells induced by aplidine.

Aplidine, dehydrodidemnin B, is a marine depsipeptide isolated from the Mediterranean tunicate Aplidium albicans currently in phase II clinical trial. In human Molt-4 leukaemia cells Aplidine was found to be cytotoxic at nanomolar concentrations and to induce both a G(1) arrest and a G(2) blockade. The drug-induced cell cycle perturbations and subsequent cell death do not appear to be related to macromolecular synthesis (protein, RNA, DNA) since the effects occur at concentrations (e.g. 10 nM) in which macromolecule synthesis was not markedly affected. Ten nM Aplidine for 1 h inhibited ornithine decarboxylase activity, with a subsequently strong decrease in putrescine levels. This finding has questionable relevance since addition of putrescine did not significantly reduce the cell cycle perturbations or the cytotoxicity of Aplidine. The cell cycle perturbations caused by Aplidine were also not due to an effect on the cyclin-dependent kinases. Although the mechanism of action of Aplidine is still unclear, the cell cycle phase perturbations and the rapid induction of apoptosis in Molt-4 cells appear to be due to a mechanism different from that of known anticancer drugs.

Isolation and characterization of an IGROV-1 human ovarian cancer cell line made resistant to Ecteinascidin-743 (ET-743).

By exposing Igrov-1 human ovarian cancer cells to increasing concentrations of Ecteinascidin-743 (ET-743), either for a short or prolonged time, we obtained sublines resistant to ET-743 which overexpress Pgp. The most resistant clone (Igrov-1/25 ET) was evaluated for biological and pharmacological characterizations. The increased Pgp levels of Igrov-1/25 ET were not due to amplification of the mdr-1 gene but to increased mRNA levels. No increase in other multidrug resistance-related proteins such as MRP or LRP was observed in Igrov-1/25 ET. The IC50 values of ET-743 against Igrov-1/25 ET was approximately 50 times higher than the parental cell line. Resistance was not reversed while maintaining the cell line in drug-free medium for at least 24 months. Igrov-1/25 ET was cross-resistant to Doxorubicin and VP16 while it was equally sensitive to L-PAM, MNNG, CPT and only marginally less sensitive to Cis-DDP and Oxaliplatin compared to the parental cell line. Igrov-1/25 ET exposed to Doxorubicin retained this drug much less, mainly because of a more efficient drug efflux. The cyclosporine analogue SDZ PSC-833 reversed the resistance of Igrov-1/25 ET to ET-743, without any enhancement of the drug activity against the parental Igrov-1 cell line. Igrov-1/25 ET exhibits typical features of cell lines overexpressing the mdr-1 gene and can be a potentially useful tool in selecting ET-743 non-cross-resistant analogues as well as to investigate methods to counteract resistance to this drug.

Hormonal state rather than age influences cut-off values of protein S: reevaluation of the thrombotic risk associated with protein S deficiency.

Of the well known risk factors for thrombosis protein S deficiency is one of the most difficult to diagnose with certainty. Reliable estimates for the prevalence of protein S deficiency in the general population are not available and the risk of thrombosis is a controversial issue. It has been shown that levels of protein S fluctuate over time. However the determinants of low levels of protein S in the healthy population are not clear. Therefore. we evaluated the influence of sex, age and hormonal state on the antigen levels of protein S in 474 healthy control subjects of the Leiden Thrombophilia Study (LETS). In univariate analysis, sex, age, oral contraceptive (OC) use and post-menopausal state all influenced protein S antigen levels. In a multivariate model for the whole sample only menopausal state and OC use had still an effect on the levels of total protein S and only menopausal state had an independent effect on the values of free protein S. On the basis of this analysis we established different cut-off levels for these subgroups and we re-evaluated in the Leiden Thrombophilia Study the risk of thrombosis for individuals with low protein S using these different reference ranges. With these specific cut-off points, we did not observe an increase in the risk of thrombosis in patients deficient of total protein S (OR 1.2, 95% CI 0.5-2.9) or free protein S (OR 1.3, 95% CI 0.5-3.5). When men and women were analyzed separately, the risk in women was 1.5 (95% CI 0.4-5.4) and 2.4 (95% CI 0.6-9.2) for total and free protein S deficiencies, respectively; and there was no increase in thrombotic risk for men. We conclude that it may be helpful to apply separate cut-off levels in the assessment of protein S levels. This does not, however explain the differences between our results and those of others in the estimate of thrombotic risk of protein S deficiency.

High-dose therapy and autologous bone marrow transplantation for adult patients with lymphoblastic lymphoma: results of the European Group for Bone Marrow Transplantation.

PURPOSE: To investigate the results of treatment and factors that affect prognosis in adult patients undergoing high-dose therapy and autologous bone marrow transplantation (ABMT) for lymphoblastic lymphoma (LBL). PATIENTS AND METHODS: The study was a retrospective analysis of 214 patients reported to the Lymphoma Registry of the European Group for Bone Marrow Transplantation (EBMT) between January 1981 and December 1992, including 105 patients undergoing marrow transplantation in first complete remission (CR). Data on all patients were reviewed, and analysis of prognostic factors conducted. RESULTS: The actuarial overall survival rate at 6 years for the entire group is 42%. Disease status at ABMT was the major determinant of outcome: 6-year actuarial overall survival was 63% for patients transplanted in first CR, compared with 15% for those with resistant disease at the time of transplantation. Transplantation in second CR resulted in a 31% rate of actuarial overall survival at 6 years. For patients transplanted in first CR, univariate analysis failed to identify any factors at presentation that predicted for outcome after transplantation. CONCLUSION: These results suggest that ABMT is effective therapy for adults with LBL, even in patients with disease that is resistant to conventional-dose therapy. Results for patients transplanted in second CR are superior to those reported for conventional-dose salvage regimens. The results in first CR require verification in a prospective randomized clinical study.

[Intestinal occlusion and perforation as a complication in percutaneous endoscopic gastrotomy (PEG)]. / Occlusione e perforazione intestinale quale complicanza in gastrotomia endoscopica percutanea (PEG).

Complications in the removal of PEG have rarely been reported. Especially patients been operated for head and neck cancer can be a serious problem for the removal of percutaneous endoscopic gastrostomy. A case of an incomplete removal of PEG and occlusion of the lower bowel with subsequent perforation is reported.

High dose cyclophosphamide: stem cell mobilizing capacity in 21 patients.

In the present study we assess the antitumor effect and circulating stem cells (CSC) mobilizing capacity of high-dose cyclophosphamide (5 to 7 gr/m2, HDCY). This treatment was given to 21 patients with various hematologic malignancies (8 NHL, 5 MM, 4 HD, 3 CML) excluding 1 with neuroblastoma. All were eligible for later autologous blood stem cell transplantation (ABSCT). To reduce the hematologic toxicity of HDCY, GM CSF was simultaneously administered in 5 patients. HDCY produced a response (as defined by a > 50% reduction of previous tumor mass) in 3 out of 12 HD/NHL and 1 out of 3 MM. Patients with CML were not considered to be evaluable for tumor response. Cell collection yields after HDCY varied widely with a range of 1.5 to 169.9 x 10(4)/Kg (median 13.1) CFU-GM and 1.7 to 18.4 x 10(8)/Kg (median 5.8) MNC collected per patient. Hematologic recovery was rapid and sustained with a median of 16 (12-18) days to PMN > 0.5 x 10(9)/L and 14 (11-18) days to Plt > 100.0 x 10(9)/L. Granulocyte recovery was significantly faster after GM-CSF (13 vs 16 days to PMN > 0.5, p = 0.0008). Non hematologic toxicity consisted mainly of nausea and vomiting, but fatal complications occurred in 2 patients, from pulmonary infection in one and from tumor-lysis syndrome in the other. HDCY represents a useful means of increasing collection of CSC, but toxicity is not irrelevant. Whether a similar anti-tumor effect and mobilizing capacity would be offered by single lower intermediate doses of the drug is still to be ascertained.

Comparison of peripheral blood stem-cell and autologous bone marrow transplantation for lymphoma patients: a case-controlled analysis of the EBMT Registry data. Lymphoma Working Party of the EBMT.

A case-controlled analysis was performed to assess the effect of stem-cell source on autograft in a group of patients with malignant lymphoma reported to the European Bone Marrow Transplant Group (EBMT). The study was performed matching 83 patients autografted with peripheral blood stem cells (PBSC) with 83 autologous bone marrow transplantation (ABMT) patients. The case-matching was carried out following selection of the main prognostic factors for progression-free survival by multivariate analysis. The progression-free survival was similar in both types of transplants (38.5% PBSCT vs. 36.4% ABMT). The overall relapse and progression rate for the PBSCT was 51.2% compared with 50.1% for the ABMT patients. The differences were not significant statistically. The transplant-related mortality was 6% for both groups. The neutrophil and leucocyte recovery occurred faster in the peripheral blood stem-cell transplantation (PBSCT); the platelet recovery was not significant. A higher number of interstitial pneumonitis and fungal infection episodes were observed in the ABMT group. In conclusion, in these closely matched groups, there is no difference in PFS between patients undergoing PBSCT and those undergoing ABMT. However, the patients autografted with PBSC have a more rapid engraftment and a lower toxicity.

Cyclophosphamide 4 g/m2 plus rhG-CSF for mobilization of circulating progenitor cells in malignant lymphomas.

We report the preliminary results of a study exploring the possibility of collecting circulating progenitor cells (PBSC) with a protocol based on the administration of single doses (4 g/m2) of cyclophosphamide and G-CSF (5 or 10-micrograms/kg) in 9 patients with non Hodgkin's lymphoma. The peak level of CD34+ cells occurred after a median of 10 days (range 8-11), generally coinciding with the median peak level of CFU-GM, with a mean 31.27 fold increase above basal levels. 3 (range 2-5) leukaphereses were required to harvest a median number of 25.1 x 10(4)/kg (8-105) CFU-GM and of 9.4 x 10(6)/kg (1.2-25) CD34+ cells. No difference was recorded between 5 and 10 micrograms/kg of G-CSF in terms of PBSC yield. In transplanted patients, a strong correlation was found between CD34+ cells infused/kg and platelet recovery (r = -0.8, p = 0.002). No toxicity was observed and apheretic procedures were regularly performed outpatiently. Our conclusion is that this protocol is particularly suitable for an outpatient treatment/collection program.

High-dose cyclophosphamide, etoposide and BCNU (CVB) with autologous stem cell rescue in malignant lymphomas.

Eighteen patients with malignant lymphoma, 10 non-Hodgkin's and 8 Hodgkin's, were treated with high-dose CVB (cyclophosphamide 4 x 1.5 g/m2, etoposide 4 x 250-400 mg/m2, carmustine 4 x 150-200 mg/m2), followed by autologous peripheral blood stem cells (PBSC, 13 patients) or bone marrow (BM, 5 patients) transplantation. At the time of autograft 6 patients were in complete remission (CR), 3 in partial remission (PR) and 5 in relapse (4 sensitive, 1 resistant), whereas 4 had progressive disease. All CR patients had poor prognostic features at presentation. PBSC were collected at the time of rapid hematologic recovery after intense chemotherapy by means of a cell separator. All patients engrafted. Median time to achieve > or = 0.5 x 10(9)/l polymorphonuclear cells (PMN) and > or = 50 x 10(9)/l platelets was 13 days for both cell types in PBSC autografted patients, versus 20 and 28 days respectively in BM autografted patients. A significant advantage of PBSC over BM was found in terms of time needed to recover either PMN > or = 0.5 and PMN > or = 1 x 10(9)/l (p = 0.01). Autograft-related toxicity consisted mainly of moderate severity interstitial pneumopathy (3 patients), and veno-occlusive disease (1 patient) that resolved completely. Of the 12 patients autografted with detectable disease, 6 (50%) obtained a CR. Seven out of 18 autografted patients (39%) had disease progression within 1 to 5 months of autograft. The projected progression-free survival is over 50% at 4 years and it was significantly longer in patients with sensitive disease than in those with resistant disease (p = 0.01). The efficacy and the low toxicity of CVB suggest that autograft with PBSC may be proposed for the primary treatment of poor prognosis malignant lymphomas.

Central catheter infection by Trichosporon beigelii after autologous blood stem cell transplantation. A case report and review of the literature.

A case of localized Trichosporon beigelii infection is reported in a 40-year-old woman with Ph+ chronic granulocyte leukemia who underwent autologous blood stem cell transplantation. On day +14 after autograft, while severely neutropenic, she developed a local infection involving the soft tissues surrounding the central venous catheter (CVC) point of entry into the subclavian vein. Trichosporon beigelii was isolated from culture of the CVC tip; resolution occurred after removal of the CVC, neutrophil recovery and antifungal treatment with amphotericin B and 5-fluorocytosine. To our knowledge this is the first case of CVC localized infection from Trichosporon beigelii after transplantation.

High-dose therapy and autologous transplantation in amyloidosis-AL.

A 53-yr.-old woman with amyloidosis AL was treated with high-dose chemotherapy and autologous stem cell infusion in an attempt to suppress the amyloid secretion. A diagnosis of MGUS had been made six years earlier. During the last year her disease had progressively shifted to a full-blown picture of amyloidosis AL, with renal failure, proteinuria, renal amyloid deposition and plasma cell sheets in the marrow. After an unsuccessful attempt with standard-dose chemotherapy, she received a high-dose regimen of busulphan (14 mg/Kg) and melphalan (40 mg/m2), followed by the infusion of both autologous bone marrow and peripheral blood stem cells. She had full and prompt engraftment, but eight weeks post-graft developed interstitial pneumonitis: CMV was isolated. The patient died while in the intensive care unit. In the literature, this is the first case of amyloidosis AL treated with high-dose therapy and autologous transplantation.

Hippocampal seizures and striatal regulation: a possible functional pathway.

Experimental findings have suggested the possibility of a functional relationship between the basal ganglia and the hippocampus. Previous research has revealed a predominantly inhibitory action of the caudate nucleus (CN) and an excitatory effect of the globus pallidus (GP) on electrically induced hippocampal afterdischarges (HAD). The effects of electrolytic destruction of the CN on the threshold and duration of HAD has been studied in the 'encéphale isolé' cat. The threshold and duration of HAD was also studied following conditioning stimulation of the CN in animals in which the inner segment of the globus pallidus (GPi) and medial septal nucleus (MSN) had been destroyed. Following CN lesions, the hippocampal excitability threshold underwent a significant reduction, while the duration of HAD appeared to be increased. Following destruction of the GPi and MSN, the threshold and duration of HAD exhibited no change following conditioning stimulation of the CN. The results reveal a tonic inhibitory effect of the CN on the hippocampus and suggest that a strio-pallido-septal pathway is the anatomical substrate for the effect.

Modulation of paroxysmal activity in the hippocampus by caudate stimulation in the chronic cat.

Afterdischarges in the dorsal hippocampus (HADs) were studied in freely-moving cats with implanted electrodes following threshold stimulation of the mirror-image point on the contralateral side. Marked inhibition, similar so that seen in acute animals, was observed when the test stimulation was immediately preceded by a conditioning stimulus applied to the caudate nucleus. The inhibitory effect appeared to be larger in these chronic animals than in the acute preparations previously studied, probably because of the total absence of anaesthesia during the recording session. When the HAD is preceded by caudate stimulation, its duration can be graduated by the intensity of the hippocampal test stimulation. The results are discussed in terms of a possible modulation induced directly or indirectly by the caudate nucleus in the hippocampus, which reacts in a gradual manner to the excitatory volley.

Effects of substantia nigra and pallidum stimulation on hippocampal interictal activity in the cat.

In the present work the role played by substantia nigra pars compacta and globus pallidus pars interna on hippocampal bioelectrical activity is studied. Injections of sodium penicillin (i.v.) produce steady interictal spikes in the hippocampus. Substantia nigra stimulation induces regular theta rhythm and inhibits the spikes. Pallidal stimulation, on the contrary, appears to strongly enhance epileptiform activity, proceeding to generalized seizure activity. The results are discussed in the light of the interrelationships between basal ganglia and hippocampus, hypothesizing a putative feedback loop from striatal to limbic centers.

Striatal and septal influence on hippocampal theta and spikes in the cat.

The experiments studied the modulation exerted by the septum and the caudate nucleus on hippocampal activity in the cat. Injections (i.v.) of sodium penicillin were performed in order to obtain a steady interictal epileptic activity. Hippocampal slow rhythmic activity showed a marked decrease either in duration or in frequency following penicillin activation. Both septal and caudate electrical stimulation inhibited spike frequency through a theta eliciting mechanism. Caudate stimulation failed to determine any sort of effect after medial septum lesions. The importance of the septum as modulation station between basal ganglia and hippocampus is emphasized.