Complete inhibition of extranodal dissemination of lymphoma by edelfosine-loaded lipid nanoparticles

Lipid nanoparticles (LN) made of synthetic lipids Compritol® 888 ATO and Precirol® ATO 5 were developed, presenting an average size of 110.4 ± 2.1 nm and 103.1 ± 2.9 nm, for Compritol® and Precirol®, respectively, and encapsulation efficiency above 85 % for both type of lipids. These LN decrease the hemolytic toxicity of the drug by 90 %. Pharmacokinetic and biodistribution profiles of the drug were studied after intravenous and oral administration of edelfosine-containing LN, providing an increase in relative oral bioavailability of 1500 % after a single oral administration of drug-loaded LN, maintaining edelfosine plasma levels over 7 days in contrast to a single oral administration of edelfosine solution, which presents a relative oral bioavailability of 10 %. Moreover, edelfosine-loaded LN showed a high accumulation of the drug in lymph nodes and resulted in slower tumor growth than the free drug in a murine lymphoma xenograft model, as well as potent extranodal dissemination inhibition

Synthesis and Biological Evaluation of New Podophyllic Aldehyde Derivatives with Cytotoxic and Apoptosis-Inducing Activities

Several series of nonlactonic podophyllic aldehyde analogues were prepared and evaluated against several human tumor cell lines. They had different combinations of aldehyde, imine, amine, ester, and amide functions at C-9 and C-9′ of the cyclolignan skeleton. All the compounds synthesized showed cytotoxicity levels in the μM range and below. Within the new series tested, compounds having an aldehyde or imine at C-9 and an ester at C-9′ were the most potent, with GI50 values in the nM range, some of them being several times more potent against HT-29 and A-549 carcinoma than against MB-231 melanoma cells. Cell cycle studies and analysis of the microtubule-disrupting capacity have demonstrated the existence of two different mechanisms of cell death induction for compounds with closely related structures. © 2010 American Chemical Society.Financial support came from Spanish Ministerio de Ciencia y Tecnología (CTQ2008-02899, SAF2008-02251), Red Temática de Investigación Cooperativa en Cáncer, Instituto de Salud Carlos III (RD06/0020/1037), and Junta de Castilla y León (SA 005A08 and fellowship to M. V.R.). We thank Dr. H. B. Broughton for his help with proofreading.Peer Reviewe

Intracellular location of syntaxin 7 in human neutrophils

Neutrophils are the first line of defense in the innate immune system. Neutrophils neutralize invading microorganisms mainly by phagocytosis, but the mechanism and molecules involved in this process are not well characterized. Because the endosomal soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) protein syntaxin 7 regulates vesicle trafficking events in phagocytosis, we investigated the expression and subcellular localization of syntaxin 7 in human neutrophils. Here we have found that human peripheral blood neutrophils and neutrophil-differentiated HL-60 cells express syntaxin 7 at both mRNA and protein levels. Using biochemical and ultrastructural approaches, we found that syntaxin 7 was broadly located in the membranes of the three major cytoplasmic granules of human neutrophils, with a major location in azurophilic granules, which are mainly involved in phagocytosis. A secondary, but extensive, location of syntaxin 7 was in specific and tertiary granules, which resulted translocated to the plasma membrane upon cell activation that promoted mobilization of these organelles. These data reveal the presence of syntaxin 7 in the membranes of exocytosis-prone granules (specific and tertiary granules) and phagocytosis-related granules (azurophilic granules) in human neutrophils, and therefore it might play a role in both exocytosis and phagocytosis in human neutrophils.This work was supported in part by grants from the Spanish Ministry of Science and Innovation (SAF2008-02251, and RD06/0020/1037 from Red Temática de Investigación Cooperativa en Cáncer, Instituto de Salud Carlos III, cofunded by the Fondo Europeo de Desarrollo Regional of the European Union), Junta de Castilla y León (CSI01A08, GR15-Experimental Therapeutics and Translational Oncology Program, and Biomedicine Project 2009), and Fundación “la Caixa” (BM05-30-0).Peer Reviewe

DNA and non-DNA targets in the mechanism of action of the antitumor drug trabectedin

We have analyzed the DNA binding properties of the antitumor agent trabectedin (ET-743, Yondelis) and different analogs, namely, ET-745, lacking the C21-hydroxyl group, and ET-637, ET-594, ET-637-OBu, with modifications at the trabectedin C domain, versus their effects on cell cycle, apoptosis, and gene expression. ET-745 failed to bind DNA, highlighting the importance of the C21-hydroxyl group for DNA binding. Analogs ranked trabectedin ≫ ET-637 ≈ ET-594 > ET-637-OBu ≫ ET-745 for their DNA binding capacity; ET-637 and ET-594 display very different biological activities. Drugs were clustered in three major groups showing high (trabectedin, ET-637), intermediate (ET-637-OBu), and low (ET-594, ET-745) cytotoxic activity and similar transcriptional profiling responses. C21-hydroxyl-deficient analogs of the above-mentioned compounds showed a dramatic decrease in biological activity. Our data suggest that trabectedin interacts with an additional non-DNA target to raise an effective antitumor response, and that this interaction is favored through trabectedin-DNA complexes. ©2005 Elsevier Ltd All rights reserved.This work was supported by grants from Fondo de Investigación Sanitaria and European Commission (FIS04/0843, FIS02/1199), Fundación de Investigación Médica Mutua Madrileña (FMM), Fundación ‘‘la Caixa’’ (BM05-30-0), Junta de Castilla y León (CSI04A05) (to F.M.) C.G. was supported by the Ramón y Cajal Program from the Ministerio de Educación y Ciencia of Spain.Peer Reviewe

Lipid raft-mediated Akt signaling as a therapeutic target in mantle cell lymphoma

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.Recent evidence shows that lipid raft membrane domains modulate both cell survival and death. Here, we have found that the phosphatidylinositol-3-kinase (PI3K)/Akt signaling pathway is present in the lipid rafts of mantle cell lymphoma (MCL) cells, and this location seems to be critical for full activation and MCL cell survival. The antitumor lipids (ATLs) edelfosine and perifosine target rafts, and we found that ATLs exerted in vitro and in vivo antitumor activity against MCL cells by displacing Akt as well as key regulatory kinases p-PDK1 (phosphatidylinositol-dependent protein kinase 1), PI3K and mTOR (mammalian TOR) from lipid rafts. This raft reorganization led to Akt dephosphorylation, while proapoptotic Fas/CD95 death receptor was recruited into rafts. Raft integrity was critical for Ser473 Akt phosphorylation. ATL-induced apoptosis appeared to correlate with the basal Akt phosphorylation status in MCL cell lines and primary cultures, and could be potentiated by the PI3K inhibitor wortmannin, or inhibited by the Akt activator pervanadate. Classical Akt inhibitors induced apoptosis in MCL cells. Microenvironmental stimuli, such as CD40 ligation or stromal cell contact, did not prevent ATL-induced apoptosis in MCL cell lines and patient-derived cells. These results highlight the role of raft-mediated PI3K/Akt signaling in MCL cell survival and chemotherapy, thus becoming a new target for MCL treatment. © 2013 Macmillan Publishers Limited.This work was supported by grants from Ministerio de Economía y Competitividad of Spain (SAF2008-02251 and SAF2011-30518 to FM; SAF2009-09503 to DC), Red Temática de Investigación Cooperativa en Cáncer, Instituto de Salud Carlos III, cofunded by the Fondo Europeo de Desarrollo Regional of the European Union (RD06/0020/1037 and RD12/0036/0065 to FM; RD06/0020/0014 to DC), Fondo de Investigación Sanitaria and European Commission, Instituto de Salud Carlos III (PI09/0060 to GR; PS09/01915 to CG), European Community’s Seventh Framework Programme FP7-2007-2013 (grant HEALTH-F2-2011-256986, PANACREAS to FM), Junta de Castilla y León (CSI052A11-2 and CSI221A12-2 to FM; Biomedicine Project 2010–2011 to CG) and Generalitat de Catalunya (2009SGR967 to DC). MRS was recipient of a predoctoral fellowship from the Fundaçâo para a Ciência e Tecnologia (Ministério da Ciencia, Tecnología e Ensino Superior of Portugal), and AM was a recipient of a predoctoral fellowship from IDIBAPS. CG was supported by the Ramón y Cajal Program from the Ministerio de Ciencia e Innovación of Spain.Peer Reviewe

Synthesis of novel antitumoural analogues of dysidiolide from ent-halimic acid

Several sesterterpenolides analogues of dysidiolide have been synthesized and their in vitro antitumoural activity against human HeLa, A549, HT-29 and HL-60 carcinoma cells is presented. The proliferation inhibition data showed a significant antitumour activity of the compounds 1b, 2a, 2b, 3a, 3b, 4a, 4b, 5, inhibiting proliferation of distinct cancer cell types with an IC50 in the low micromolar range. © 2007 Elsevier Ltd. All rights reserved.The authors are grateful to the CICYT (CTQ2005- 04406) for financial support and the Junta de Castilla y León for a grant to M.A.E.Peer Reviewe

Edelfosine Induces an Apoptotic Process in Leishmania infantum That Is Regulated by the Ectopic Expression of Bcl-XL and Hrk▿

The alkyl-lysophospholipids edelfosine and miltefosine induce apoptosis in Leishmania infantum promastigotes. The finding that edelfosine-induced cell death can be regulated by the ectopic expression of the antiapoptotic and proapoptotic members of the Bcl-2 family of proteins Bcl-XL and Hrk suggests that this process is similar to apoptosis in eukaryotic cells

In vitro and in vivo selective antitumor activity of edelfosine against mantle cell lymphoma and chronic lymphocytic leukemia involving lipid rafts

[Purpose]: Mantle cell lymphoma (MCL) and chronic lymphocytic leukemia (CLL) remain B-cell malignancies with limited therapeutic options. The present study investigates the in vitro and in vivo effect of the phospholipid ether edelfosine (1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine) in MCL and CLL. [Experimental Design]: Several cell lines, patient-derived tumor cells, and xenografts in severe combined immunodeficient mice were used to examine the anti-MCL and anti-CLL activity of edelfosine. Furthermore, we analyzed the mechanism of action and drug biodistribution of edelfosine in MCL and CLL tumor-bearing severe combined immunodeficient mice. [Results]: Here, we have found that the phospholipid ether edelfosine was the most potent alkyl-lysophospholipid analogue in killing MCL and CLL cells, including patient-derived primary cells, while sparing normal resting lymphocytes. Alkyl-lysophospholipid analogues ranked edelfosine > perifosine ≫ erucylphosphocholine ≥ miltefosine in their capacity to elicit apoptosis in MCL and CLL cells. Edelfosine induced coclustering of Fas/CD95 death receptor and rafts in MCL and CLL cells. Edelfosine was taken up by malignant cells, whereas normal resting lymphocytes hardly incorporated the drug. Raft disruption by cholesterol depletion inhibited drug uptake, Fas/CD95 clustering, and edelfosine-induced apoptosis. Edelfosine oral administration showed a potent in vivo anticancer activity in MCL and CLL xenograft mouse models, and the drug accumulated dramatically and preferentially in the tumor. [Conclusions]: Our data indicate that edelfosine accumulates and kills MCL and CLL cells in a rather selective way, and set coclustering of Fas/CD95 and lipid rafts as a new framework in MCL and CLL therapy. Our data support a selective antitumor action of edelfosine.Ministerio de Ciencia e Innovación grants SAF2005-04293, SAF2006-8850, SAF2007-61261, SAF2007-60964, PCT-090100-2007-27, PS09/01915, and SAF2008-02251; Red Temática de Investigación Cooperativa en Cáncer grants RD06/0020/0014, RD06/0020/0097, and RD06/0020/1037 (Instituto de Salud Carlos III, cofunded by the Fondo Europeo de Desarrollo Regional of the European Union); Fondo de Investigación Sanitaria and European Commission grant FIS-FEDER 06/0813; Junta de Castilla y León (CSI01A08, GR15-Experimental Therapeutics and Translational Oncology Program, and Biomedicine Project 2009); Fundación de Investigación Médica Mutua Madrileña; Fundación “la Caixa” grant BM05-30-0; Caja Navarra Foundation; Department of Health of the Government of Navarra (“Ortiz de Landázuri, 2009” project); and AGAUR-Generalitat de Catalunya grant 2005SGR-00549. C. Gajate is supported by the Ramón y Cajal Program from the Ministerio de Ciencia e Innovación of Spain. A. Estella-Hermoso de Mendoza is supported by Department of Education of the Basque Government research grant BFI06.37. M. de Frias is a recipient of a fellowship from the AGAUR-Generalitat de Catalunya. G. Roué holds a Miguel Servet research contract from Instituto de Salud Carlos III.Peer Reviewe

Complete inhibition of extranodal dissemination of lymphoma by edelfosine-loaded lipid nanoparticles

[Background]: Lipid nanoparticles (LNs) made of synthetic lipids Compritol® 888 ATO and Precirol® ATO 5 were developed with an average size of 110.4 ± 2.1 and 103.1 ± 2.9 nm, and an encapsulation efficiency above 85% for both type of lipids. These LNs decrease the hemolytic toxicity of the drug by 90%. [Materials & methods]: Pharmacokinetic and biodistribution profiles of the drug were studied after intravenous and oral administration of edelfosine-containing LNs. [Results]: This provided an increase in relative oral bioavailability of 1500% after a single oral administration of drug-loaded LNs, maintaining edelfosine plasma levels over 7 days in contrast to a single oral administration of edelfosine solution, which presented a relative oral bioavailability of 10%. Moreover, edelfosine-loaded LNs showed a high accumulation of the drug in lymph nodes and resulted in slower tumor growth than the free drug in a murine lymphoma xenograft model, as well as potent extranodal dissemination inhibition. Original submitted 5 April 2011; Revised submitted 5 July 201. © 2012 Future Medicine Ltd.Peer Reviewe