12 research outputs found
Phase I/II trial of doxorubicin and fixed dose-rate infusion gemcitabine in advanced soft tissue sarcomas: a GEIS study
The aim of the study was to determine the dose-limiting toxicity and maximum tolerated dose of a first-line combination of doxorubicin and gemcitabine in adult patients with advanced soft tissue sarcomas and to explore its activity and toxicity, and the presence of possible interactions between these agents. Patients with measurable disease were initially treated with doxorubicin 60âmgâmâ2 by i.v. bolus on day 1 followed by gemcitabine at 800âmgâmâ2 over 80âmin on days 1 and 8, every 21 days. Concentrations of gemcitabine and 2âČ,2âČ-difluorodeoxyuridine in plasma, and gemcitabine triphosphate levels in peripheral blood mononuclear cells were determined during 8âh after the start of gemcitabine infusion. Myelosuppression and stomatitis were limiting toxicities, and the initial dose level was applied for the Phase II trial, where grade 3â4 granulocytopenia occurred in 70% of patients, grade 3 stomatitis in 46% and febrile neutropenia in 20%. Objective activity in 36 patients was 22% (95% CI: 9â35%), and a 50% remission rate was noted in leiomyosarcomas. Administration of doxorubicin preceding gemcitabine significantly reduced the synthesis of gemcitabine triphosphate. Clinical activity, similar to that of single-agent doxorubicin, and the toxicity encountered do not justify further studies with this schedule of administration
Sex-specific cardiac cardiolipin remodelling after doxorubicin treatment
BACKGROUND: Imbalance in lipid metabolism and membrane lipid homeostasis has been observed in numerous diseases including heart failure and cardiotoxicity. Growing evidence links phospholipid alterations especially cardiolipins (CLs) to defects in mitochondrial function and energy metabolism in heart failure. We have shown recently that doxorubicin cardiotoxicity is more severe in male than female Wistar rats. We aimed to study whether this sex specificity is linked to differences in cardiac phospholipid profiles. RESULTS: Adult male and female rats were injected 2Â mg/kg doxorubicin weekly for 7Â weeks. Cardiac phospholipid molecular species were determined by liquid chromatography coupled with mass spectrometry fragmentation (LC)/MS(n). Sex difference in phosphatidylethanolamine and phosphatidylcholine species containing docosahexaenoic and docosapentaenoic acyl chains was observed, females having more than males. In both sexes, doxorubicin induced an important loss of the main CL(18:2)(4), while the level of monolysocardiolipin MLCL(18:2)(3) remained stable. However, a severe remodelling appeared in treated rats with the longest CL acyl chains in doxorubicin-treated females, which might compensate for the loss of tetra-linoleoyl CL. The level of oxidized cardiolipin was not particularly increased after doxorubicin treatment. Finally, expression of genes involved in the biosynthesis of fatty acid appeared to be decreased in doxorubicin-treated males. CONCLUSIONS: These results emphasize for the first time the cardiac remodelling in the phospholipid classes after doxorubicin treatment. These observations suggest that doxorubicin has a sex-specific impact on the heart phospholipidome especially on cardiolipin, an essential mitochondrial lipid. Further studies are needed to better understand the roles of lipids in the anthracycline cardiotoxicity and sex differences, but phospholipid cardioprotection seems a valuable new additive therapeutic strategy for anthracycline cardiotoxicity. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13293-015-0039-5) contains supplementary material, which is available to authorized users