Second-line treatment with irinotecan plus cisplatin vs cisplatin of patients with advanced non-small-cell lung cancer pretreated with taxanes and gemcitabine: a multicenter randomised phase II study.

The aim of this study was to compare the irinotecan/cisplatin regimen with cisplatin as second-line chemotherapy in patients with advanced non-small-cell lung cancer (NSCLC) pretreated with a taxane/gemcitabine regimen. Patients (n = 147) with stage IV NSCLC pretreated with a taxane/gemcitabine regimen were randomly assigned to receive either irinotecan (110 mg m(-2), day 1 and 100 mg m(-2), day 8) and cisplatin (80 mg m(-2), day 8) (IC; n = 74) or CDDP (80 mg m(-2), day 1) (C; n = 73) every 3 weeks. Patients treated with IC and C had a median survival of 7.8 and 8.8 months, respectively (P = 0.933). The 1-year survival rate was 34.3% for IC-treated patients and 31.7% for C-treated patients. Cox's regression analysis revealed that response to treatment (hazard ratio (HR) = 2.787; 95% confidence interval (CI): 1.1578-4.922) and performance status (HR = 1.865; 95% CI: 1.199-2.872) was independent prognostic factors for survival. Overall response rate was 22.5% (95% CI: 12.8-32.2%) for IC-treated patients and 7.0% (95% CI: 1.15-13.6%) for C-treated patients (P = 0.012); tumour growth control (partial remission (PR) + stable disease (SD)) was observed in 26 (38%) IC and 25 (36%) C patients (P = 0.878). There was no difference in terms of quality of life between the two chemotherapy arms. The incidence of febrile neutropenia, grade 3 and 4 neutropenia and grade 3 and 4 diarrhoea was significantly higher in the IC- than the C-treated patients. Other toxicities were mild. There were no treatment-related deaths in either arm. The IC regimen did not confer a survival benefit compared with C as second-line treatment of patients with advanced NSCLC pretreated with a taxane/gemcitabine regimen, despite its better efficacy in terms of response rate.

Competition between Li+ and Mg2+ in neuroblastoma SH-SY5Y cells: a fluorescence and 31P NMR study.

Because Mg2+ and Li+ ions have similar chemical properties, we have hypothesized that Li+/Mg2+ competition for Mg2+ binding sites is the molecular basis for the therapeutic action of lithium in manic-depressive illness. By fluorescence spectroscopy with furaptra-loaded cells, the free intracellular Mg2+ concentration within the intact neuroblastoma cells was found to increase from 0. 39 +/- 0.04 mM to 0.60 +/- 0.04 mM during a 40-min Li+ incubation in which the total intracellular Li+ concentration increased from 0 to 5.5 mM. Our fluorescence microscopy observations of Li+-free and Li+-loaded cells also indicate an increase in free Mg2+ concentration upon Li+ incubation. By 31P NMR, the free intracellular Mg2+ concentrations for Li+-free cells was 0.35 +/- 0. 03 mM and 0.80 +/- 0.04 mM for Li+-loaded cells (final total intracellular Li+ concentration of 16 mM). If a Li+/Mg2+ competition mechanism is present in neuroblastoma cells, an increase in the total intracellular Li+ concentration is expected to result in an increase in the free intracellular Mg2+ concentration, because Li+ displaces Mg2+ from its binding sites within the nerve cell. The fluorescence spectroscopy, fluorescence microscopy, and 31P NMR spectroscopy studies presented here have shown this to be the case.

7Li nuclear magnetic resonance study for the determination of Li+ properties in neuroblastoma SH-SY5Y cells.

Lithium has been used clinically in the treatment of manic depression. However, its pharmacologic mode of action remains unclear. Characteristics of Li+ interactions in red blood cells (RBCs) have been identified. We investigated Li+ interactions on human neuroblastoma SH-SY5Y cells by developing a novel 7Li NMR method that provided a clear estimation of the intra- and extracellular amounts of Li+ in the presence of the shift reagent thulium-1,4,7,10-tetrazacyclododecane-N,N',N'',N'''-tetramethylene phosphonate (HTmDOTP4-). The first-order rate constants of Li+ influx and efflux for perfused, agarose-embedded SH-SY5Y cells in the presence of 3 mM HTmDOTP4- were 0.055 +/- 0.006 (n = 4) and -0.025 +/- 0.006 min(-1) (n = 3), respectively. Significant increases in the rate constants of Li+ influx and efflux in the presence of 0.05 mM veratridine indicated the presence of Na+ channel-mediated Li+ transport in SH-SY5Y cells. 7Li NMR relaxation measurements showed that Li+ is immobilized more in human neuroblastoma SH-SY5Y cells than in human RBCs.