Delivery of cardiovascular progenitors with biomimetic microcarriers reduces adverse ventricular remodeling in a rat model of chronic myocardial infarction.

Despite tremendous progress in cell-based therapies for heart repair, many challenges still exist. To enhance the therapeutic potential of cell therapy one approach is the combination of cells with biomaterial delivery vehicles. Here, we developed a biomimetic and biodegradable micro-platform based on polymeric microparticles (MPs) capable of maximizing the therapeutic potential of cardiac progenitor cells (CPCs) and explored its efficacy in a rat model of chronic myocardial infarction. The transplantation of CPCs adhered to MPs within the infarcted myocardial microenvironment improved the long-term engraftment of transplanted cells for up to one month. Furthermore, the enhancement of cardiac cellular retention correlated with an increase in functional recovery. In consonance, better tissue remodeling and vasculogenesis were observed in the animals treated with cells attached to MPs, which presented smaller infarct size, thicker right ventricular free wall, fewer deposition of periostin and greater density of vessels than animals treated with CPCs alone. Finally, we were able to show that part of this beneficial effect was mediated by CPC-derived extracellular vesicles (EVs). Taken together, these findings indicate that the biomimetic microcarriers support stem cell survival and increase cardiac function in chronic myocardial infarction through modulation of cardiac remodeling, vasculogenesis and CPCs-EVs mediated therapeutic effects. The biomimetic microcarriers provide a solution for biomaterial-assisted CPC delivery to the heart. STATEMENT OF SIGNIFICANCE: In this study, we evaluate the possibility of using a biomimetic and biodegradable micro-platform to improve cardiovascular progenitor therapy. The strategy reported herein serves as an injectable scaffold for adherent cells due to their excellent injectability through cardiac catheters, capacity for biomimetic three-dimensional stem cell support and controllable biodegradability. In a rat model of chronic myocardial infarction, the biomimetic microcarriers improved cardiac function, reduced chronic cardiac remodeling and increased vasculogenesis through the paracrine signaling of CPCs. We have also shown that extracellular vesicles derived from CPCs cultured on biomimetic substrates display antifibrotic effects, playing an important role in the therapeutic effects of our tissue-engineered approach. Therefore, biomimetic microcarriers represent a promising and effective strategy for biomaterial-assisted CPC delivery to the heart.

Squalenoyl-gemcitabine/edelfosine nanoassemblies: Anticancer activity in pediatric cancer cells and pharmacokinetic profile in mice.

Despite the great advances accomplished in the treatment of pediatric cancers, recurrences and metastases still exacerbate prognosis in some aggressive solid tumors such as neuroblastoma and osteosarcoma. In view of the poor efficacy and toxicity of current chemotherapeutic treatments, we propose a single multitherapeutic nanotechnology-based strategy by co-assembling in the same nanodevice two amphiphilic antitumor agents: squalenoyl-gemcitabine and edelfosine. Homogeneous batches of nanoassemblies were easily formulated by the nanoprecipitation method. Their anticancer activity was tested in pediatric cancer cell lines and pharmacokinetic studies were performed in mice. In vitro assays revealed a synergistic effect when gemcitabine was co-administered with edelfosine. Squalenoyl-gemcitabine/edelfosine nanoassemblies were found to be capable of intracellular translocation in patient-derived metastatic pediatric osteosarcoma cells and showed a better antitumor profile than squalenoyl-gemcitabine nanoassemblies alone. The intravenous administration of this combinatorial nanomedicine in mice exhibited a controlled release behavior of gemcitabine and diminished edelfosine plasma peak concentrations. These findings make it a suitable pre-clinical candidate for childhood cancer therapy.

A unique multidrug nanomedicine made of squalenoyl-gemcitabine and alkyl-lysophospholipid edelfosine.

Among anticancer nanomedicines, squalenoyl nanocomposites have obtained encouraging outcomes in a great variety of tumors. The prodrug squalenoyl-gemcitabine has been chosen in this study to construct a novel multidrug nanosystem in combination with edelfosine, an alkyl-lysophopholipid with proven anticancer activity. Given their amphiphilic nature, it was hypothesized that both anticancer compounds, with complementary molecular targets, could lead to the formation of a new multitherapy nanomedicine. Nanoassemblies were formulated by the nanoprecipitation method and characterized by dynamic light scattering, transmission electron microscopy and X-ray photoelectron spectroscopy. Because free edelfosine is highly hemolytic, hemolysis experiments were performed using human blood erythrocytes and nanoassemblies efficacy was evaluated in a patient-derived metastatic pediatric osteosarcoma cell line. It was observed that these molecules spontaneously self-assembled as stable and monodisperse nanoassemblies of 51 ±â€¯1 nm in a surfactant/polymer free-aqueous suspension. Compared to squalenoyl-gemcitabine nanoassemblies, the combination of squalenoyl-gemcitabine with edelfosine resulted in smaller particle size and a new supramolecular conformation, with higher stability and drug content, and ameliorated antitumor profile.

Transforming Growth Factor Beta 1 and Vascular Risk in Alcoholics.

INTRODUCTION: Transforming growth factor beta-1 (TGF-ß1) is a pleiotropic cytokine. Its relationship with atherosclerosis is debatable, protective or deleterious effects have been described. Alcoholics are at increased vascular risk. Although TGF-ß1 is increased in alcoholics, its role on vascular risk factors has not been analyzed. This is the objective of this study. PATIENTS AND METHODS: 79 heavy alcoholics and 34 controls were included. Calcium deposition in the aortic arch was assessed in the plain thorax X-ray film. Ankle-brachial index was recorded in 48 patients. All the patients underwent complete laboratory evaluation, including serum levels of TGF-ß1, tumor necrosis factor (TNF)-α, interleukin (IL)-4, IL-6, and interferon-γ (IFN-γ).We analyzed the relationships between TGF-ß1 and vascular risk factors by both univariate (parametric or non parametric tests), or multivariate analysis to discern on which variables TGF-ß1 levels depend. RESULTS: Serum TGF-ß1 levels were higher among patients (t = 2.73; P = 0.008), but no differences exist among cirrhotics (17246 ± 11,021 pg/mL) and non-cirrhotics (21,340 ± 12,442 pg/mL). TGF-ß1 showed significant correlations with total cholesterol (r = 0.28; P = 0.017) and HDL- cholesterol (r = 0.25; P = 0.042), and inverse correlations with body mass index (BMI; ρ = -0.37; P = 0.004), IL-4 (ρ = -0.31; P = 0.009), INF-γ (ρ = -0.28; P = 0.001), and IL-6 (ρ = -0.38; P = 0.001). By multivariate analysis, only BMI, IL-6 and HDL-cholesterol showed independent relationships with TGF-ß1. No relationships were observed with ankle-brachial index or calcium in the aortic arch, hypertension, diabetes, left ventricular hypertrophy or atrial fibrillation. CONCLUSION: TGF-ß1 levels are increased in alcoholics, but are unrelated to vessel wall calcification or arterial stiffness.

NRG1 PLGA MP locally induce macrophage polarisation toward a regenerative phenotype in the heart after acute myocardial infarction.

Neuregulin-1 loaded poly(lactic-co-glycolic acid) (PLGA) microparticles hold great promise for treating acute myocardial infarction, as they have been proved to recover heart function and induce positive heart remodelling in preclinical studies. More recently, the inflammatory response of the heart after acute myocardial infarction (AMI) has been identified as one of the major mechanisms in cardiac tissue remodelling and repair. However, the connection between neuregulin-1 PLGA microparticles and inflammation is still not well characterised. In the present study we assessed this relationship in a mouse AMI model. First, in vitro evidence indicated that neuregulin-1 PLGA microparticles induced a macrophage polarisation toward a regenerative phenotype (CD206+ cells), preventing macrophages from evolving toward the inflammatory phenotype (B7-2+ cells). This correlated with in vivo experiments, where neuregulin-1 PLGA microparticles locally improved the CD206+/B7-2+ ratio. Moreover, neuregulin-1 PLGA microparticles were administered at different time points (15 min, 24, 72 and 168 h) after infarction induction without causing secondary inflammatory issues. The time of treatment administration did not alter the inflammatory response. Taken together, these results suggest that neuregulin-1 PLGA microparticles can be administered depending on the therapeutic window of the encapsulated drug and that they enhance the heart's reparative inflammatory response after acute myocardial infarction, helping cardiac tissue repair.

Biocompatible porous metal-organic framework nanoparticles based on Fe or Zr for gentamicin vectorization.

Due to their high porosity and versatile composition and structure, nanoscaled Metal-Organic Frameworks (nanoMOFs) have been recently proposed as novel drug delivery systems, and have been demonstrated to have important capacities and potential for controlled release of different active ingredients. Gentamicin (GM; a broad spectrum aminoglycoside antibiotic indicated in bacterial septicemia therapy) has great therapeutic interest, but the associated bioavailability and toxicity drawbacks accompanying high doses and repeated administration of this free drug make its encapsulation inside new nanocarriers necessary. GM encapsulation within two different porous biofriendly Fe and Zr-carboxylates nanoMOFs was performed by a simple impregnation method, with full characterization of the resulting GM-containing solid using a large panel of techniques (X ray powder diffraction-XRPD, Fourier transform infrared spectroscopy-FTIR, thermogravimetric analysis-TGA, N2 sorption, scanning electron microscopy-SEM, dynamic light scattering-DLS, ζ-potential, fluorescence spectroscopy and molecular simulations). High reproducible encapsulation rates, reaching 600 µg of GM per·mg of formulation, were obtained using the biocompatible mesoporous iron(III) trimesate nanoparticles (NPs) MIL-100(Fe) (MIL: Materials from Institut Lavoisier). In vitro GM delivery studies were also carried out using different oral and intravenous simulated physiological conditions, with complete antibiotic release within 8 h when using protein free media, but lower release rates in the presence of proteins. Furthermore, in vitro toxicity of GM-containing MIL-100(Fe) NPs was investigated on two different cell lines: a monocyte from leukemia (THP-1) and adherent fibroblastoid cells (NIH/3T3). These nanoMOFs had a low cytotoxic profile with IC50 values up to 1 mg·mL-1, ensuring adequate cell proliferation after 24 h. Finally, antibacterial activity studies were carried out on two Gram-positive bacteria and one Gram-negative bacterium: S. aureus, S. epidermidis and P. aeruginosa, respectively. GM-loaded MIL-100(Fe) NPs exhibited the same activity as free GM, confirming that the antibiotic activity of the released GM was conserved.

Effectiveness of nanoencapsulated methotrexate against osteosarcoma cells: in vitro cytotoxicity under dynamic conditions.

Cancer is a leading cause of mortality in the world, with osteosarcoma being one of the most common types among children between 1 and 14 years old. Current treatments including preoperative chemotherapy, surgery and postoperative chemotherapy produce several side effects with limited effectiveness. The use of lipid nanoparticles as biodegradable shells for controlled drug delivery shows promise as a more effective and targeted tumor treatment. However, in vitro validation of these vehicles is limited due to fluid stagnation in current techniques, in which nanoparticles sediment onto the bottom of the wells killing the cells by asphyxiation. In the current series of experiments, results obtained with methotrexate-lipid nanoparticles under dynamic assay conditions are presented as a promising alternative to current free drug based therapies. Effects on the viability of the U-2 OS osteosarcoma cell line of recirculation of cell media, free methotrexate and blank and methotrexate containing lipid nanoparticles in a 11 µM concentration were successfully assessed. In addition, several designs for the microfluidic platform used were simulated using COMSOL-Multiphysics, optimized devices were fabricated using soft-lithography and simulated parameters were experimentally validated. Nanoparticles did not sediment to the bottom of the platform, demonstrating the effectiveness of the proposed system. Moreover, encapsulated methotrexate was the most effective treatment, as after 72 h the cell population was reduced nearly 40% while under free methotrexate circulation the cell population doubled. Overall, these results indicate that methotrexate-lipid nanoparticles are a promising targeted therapy for osteosarcoma treatment.

Brain aging and Parkinson's disease: New therapeutic approaches using drug delivery systems.

The etiology and pathogenesis of Parkinson's disease (PD) is unknown, aging being the strongest risk factor for brain degeneration. Understanding PD pathogenesis and how aging increases the risk of disease would aid the development of therapies able to slow or prevent the progression of this neurodegenerative disorder. In this review we provide an overview of the most promising therapeutic targets and strategies to delay the loss of dopaminergic neurons observed both in PD and aging. Among them, handling alpha-synuclein toxicity, enhancing proteasome and lysosome clearance, ameliorating mitochondrial disruptions and modifying the glial environment are so far the most promising candidates. These new and conventional drugs may present problems related to their labile nature and to the difficulties in reaching the brain. Thus, we highlight the latest types of drug delivery system (DDS)-based strategies for PD treatment, including DDS for local and systemic drug delivery. Finally, the ongoing challenges for the discovery of new targets and the opportunities for DDS-based therapies to improve and efficacious PD therapy will be discussed.

Tracking the in vivo release of bioactive NRG from PLGA and PEG-PLGA microparticles in infarcted hearts.

The growth factor neuregulin (NRG) is one of the most promising candidates in protein therapy as potential treatment for myocardial infarction (MI). In the last few years, biomaterial based delivery systems, such as polymeric microparticles (MPs) made of poly(lactic co glycolic acid) and polyethylene glycol (PLGA and PEG-PLGA MPs), have improved the efficacy of protein therapy in preclinical studies. However, no cardiac treatment based on MPs has yet been commercialized since this is a relatively new field and total characterization of polymeric MPs remains mandatory before they reach the clinical arena. Therefore, the objective of this study was to characterize the in vivo release, bioactivity and biodegradation of PLGA and PEG-PLGA MPs loaded with biotinylated NRG in a rat model of MI. The effect of PEGylation in the clearance of the particles from the cardiac tissue was also evaluated. Interestingly, MPs were detected in the cardiac tissue for up to 12 weeks after administration. In vivo release analysis showed that bNRG was released in a controlled manner throughout the twelve week study. Moreover, the biological cardiomyocyte receptor (ErbB4) for NRG was detected in its activated form only in those animals treated with bNRG loaded MPs. On the other hand, the PEGylation strategy was effective in diminishing phagocytosis of these MPs compared to noncoated MPs in the long term (12 weeks after injection). Taking all this together, we report new evidence in favor of the use of polymeric PLGA and PEG-PLGA MPs as delivery systems for treating MI, which could be soon included in clinical trials.

Lipid Nanosystems Enhance the Bioavailability and the Therapeutic Efficacy of FTY720 in Acute Myeloid Leukemia.

Protein phosphatase 2A (PP2A) is a serin-threonin phosphatase that regulates many proteins critical for malignant cell behavior; therefore, PP2A is considered to be a human tumor suppressor. In this study, we assessed the pharmacokinetic profile and the antileukemic effects of the PP2A activator FTY720, free or encapsulated in lipid nanoparticles, in in vitro and in vivo models of acute myeloid leukemia. FTY720 lipid nanoparticles presented diameters around 210 nm, with an encapsulation efficiency up to 75% and significantly increased FTY720 oral bioavailability. In addition, FTY720 restores PP2A phosphatase activity and decreases phosphorylation of PP2A and its targets Akt, ERK1/2 and STAT5, all implicated in the pathogenesis of acute myeloid leukemia. Moreover, FTY720 exerts an additive anti-leukemic effect in combination with drugs used in standard induction therapy. Importantly, FTY720 lipid nanoparticles were more efficient at inducing cell growth arrest and apoptosis than FTY720 solution. Finally, oral administration of FTY720 lipid nanoparticles to mice every three days was as effective in reducing acute myeloid leukemia xenograft tumor growth as daily oral administration of FTY720. These results provide the first evidence for the potential use of FTY720 lipid nanoparticles as an oral therapeutic agent in acute myeloid leukemia.

Realising the European network of biodosimetry: RENEB-status quo.

Creating a sustainable network in biological and retrospective dosimetry that involves a large number of experienced laboratories throughout the European Union (EU) will significantly improve the accident and emergency response capabilities in case of a large-scale radiological emergency. A well-organised cooperative action involving EU laboratories will offer the best chance for fast and trustworthy dose assessments that are urgently needed in an emergency situation. To this end, the EC supports the establishment of a European network in biological dosimetry (RENEB). The RENEB project started in January 2012 involving cooperation of 23 organisations from 16 European countries. The purpose of RENEB is to increase the biodosimetry capacities in case of large-scale radiological emergency scenarios. The progress of the project since its inception is presented, comprising the consolidation process of the network with its operational platform, intercomparison exercises, training activities, proceedings in quality assurance and horizon scanning for new methods and partners. Additionally, the benefit of the network for the radiation research community as a whole is addressed.

Adipose-derived stem cells combined with neuregulin-1 delivery systems for heart tissue engineering.

Myocardial infarction (MI) is the leading cause of death worldwide, and extensive research has therefore been performed to find a cure. Neuregulin-1 (NRG) is a growth factor involved in cardiac repair after MI. We previously described how biocompatible and biodegradable microparticles, which are able to release NRG in a sustained manner, represent a valuable approach to avoid problems related to the short half-life after systemic administration of proteins. The effectiveness of this strategy could be improved by combining NRG with several cytokines involved in cardiac regeneration. The present study investigates the potential feasibility of using NRG-releasing particle scaffold combined with adipose-derived stem cells (ADSC) as a multiple growth factor delivery-based tissue engineering strategy for implantation in the infarcted myocardium. NRG-releasing particle scaffolds with a suitable size for intramyocardial implantation were prepared by TROMS. Next, ADSC were adhered to particle scaffolds and their potential for heart administration was assessed in a MI rat model. NRG was successfully encapsulated reaching encapsulation efficiencies of 92.58 ± 3.84%. NRG maintained its biological activity after the microencapsulation process. ADSCs adhered efficiently to particle scaffolds within a few hours. The ADSC-cytokine delivery system developed proved to be compatible with intramyocardial administration in terms of injectability through a 23-gauge needle and tissue response. Interestingly, ADSC-scaffolds were present in the peri-infarted tissue 2 weeks after implantation. This proof of concept study provides important evidence required for future effectiveness studies and for the translation of this approach.

Comparison of pharmacokinetic profiles of PM02734 loaded lipid nanoparticles and cyclodextrins: in vitro and in vivo characterization.

PM02734 is a chemically synthesized depsipeptide derived from the marine kahalalides family with a broad spectrum of activity against solid tumors in vitro and in vivo, but presenting low bioavailability. In this work, solid lipid nanoparticles made of Precirol ATO 5 have been developed using a hot homogenization method followed by high shear homogenization and ultrasonication. These solid lipid nanoparticles show suitable size (around 150 nm) and encapsulation efficiency (nearly 70%) for the oral administration of the compound PM02734. A physical-chemical stability study was performed after 6 months of storage at different thermical conditions, concluding that solid lipid nanoparticles stored at 4 degrees C were more stable than solid lipid nanoparticles stored at 25 degrees C. The pharmacokinetic profile of drug-loaded solid lipid nanoparticles was also evaluated in Beagle dogs and compared with that of a cyclodextrin-based delivery system by means of AUC, C(max) and T(max) parameter estimation. Solid lipid nanoparticle based formulation provided a sustained release of the drug for a longer period of time than the cyclodextrins.

Realising the European Network of Biodosimetry (RENEB).

In Europe, a network for biological dosimetry has been created to strengthen the emergency preparedness and response capabilities in case of a large-scale nuclear accident or radiological emergency. Through the RENEB (Realising the European Network of Biodosimetry) project, 23 experienced laboratories from 16 European countries will establish a sustainable network for rapid, comprehensive and standardised biodosimetry provision that would be urgently required in an emergency situation on European ground. The foundation of the network is formed by five main pillars: (1) the ad hoc operational basis, (2) a basis of future developments, (3) an effective quality-management system, (4) arrangements to guarantee long-term sustainability and (5) awareness of the existence of RENEB. RENEB will thus provide a mechanism for quick, efficient and reliable support within the European radiation emergency management. The scientific basis of RENEB will concurrently contribute to increased safety in the field of radiation protection.

TH-1 and TH-2 cytokines in stable chronic alcoholics.

UNLABELLED: In alcoholics, the activation of Kupffer cells by gram negative bacteriae leads to an inflammatory response and cytokine secretion, which in turn activate T-lymphocytes. Possibly, Th-1 lymphocytes are activated first, followed by a Th-2 response. Th-2 cytokines, especially interleukin (IL)-13 (scarcely studied in alcoholics), may be involved in the progression to chronic stages. AIMS: The aim of the study was to analyze the relationship of Th-1 and Th-2 cytokines with liver function, alcohol consumption, nutritional status and survival. METHODS: Serum Th-1 [interferon-γ (IFN-γ)] and Th-2 cytokines (IL-4, IL-13), IL-10, IL-6 and tumor necrosis factor (TNF-α), were determined for 18 controls and 47 stable alcoholics with variable liver function impairment, who were followed-up during a median time of 90 months, a period during which 14 patients died. RESULTS: IL-4 was lower among patients; no differences were observed regarding IL-6, but the remaining ILs were higher among alcoholics. IL-10 and IL-13 were even higher in cirrhotics (Z = 2.88, P = 0.004, and Z = 2.09, P = 0.037, respectively). A significant, direct, correlation was observed between IL-13 and IL-10 (ρ = 0.49, P = 0.001), and non-significant, inverse ones were observed between IFN-γ and IL-13 (ρ = -0.23), IL-4 (ρ = -0.14) and IL-10 (ρ = -0.09). IL-13 and IL-10 were inversely related with liver function and, directly with immunoglobulin A levels, but not with survival. CONCLUSION: Serum IFN-γ values were increased in alcoholics, who also showed raised IL-13 and IL-10, but lower IL-4 levels. Given the immunomodulatory roles of IL-10 and IL-13, this increase may be interpreted as a compensatory rise of anti-inflammatory cytokines. We failed to find any relation with mortality.

Changes in cytokine levels during admission and mortality in acute alcoholic hepatitis.

Cytokine levels are raised in acute alcoholic hepatitis. However, there are disparate results regarding the duration of altered plasma levels, and there are also discrepancies about the relation of changes during the first 15 days after admission with short-term (in-hospital) or long-term mortality. In 56 patients with acute alcoholic hepatitis we found that IL-8, IL-4, Interferon-γ (IFN-γ), malondialdehyde and C-reactive protein remained higher in patients than in 18 age- and sex-matched controls at admission, at the 7th day and at the 15th day after admission. Moreover, IL-4 levels (and to a lesser extent, IL-10 and IFN-γ ones) increased along the three determinations. However, comparing patients who died during the admission with those who did not, there were no statistically significant differences, but there was a nearly significant trend for MDA (Z=1.89; p=0.059), with higher levels among those who died. When changes between the first and the second determinations were compared with long-term survival, only IL-8 and IFN-γ showed a relation with mortality. IFN-γ values increased among those who survived and decreased among those who died (p=0.048). IFN-γ values at the first determination also showed a relation with long-term mortality, especially when patients with IFN-γ values in the first quartile were compared with those of the 4th one (log rank=5.64; p=0.018; Breslow=4.64; p=0.031). Besides Interferon-γ, only C-reactive protein showed differences between the first and the 4th quartile regarding mortality (Log rank=4.50; p=0.034; Breslow 4.33; p=0.038). In contrast with other studies, no relation was found between TNF-α or IL-6 and mortality.

Preclinical activity of LBH589 alone or in combination with chemotherapy in a xenogeneic mouse model of human acute lymphoblastic leukemia.

Histone deacetylases (HDACs) have been identified as therapeutic targets due to their regulatory function in chromatin structure and organization. Here, we analyzed the therapeutic effect of LBH589, a class I-II HDAC inhibitor, in acute lymphoblastic leukemia (ALL). In vitro, LBH589 induced dose-dependent antiproliferative and apoptotic effects, which were associated with increased H3 and H4 histone acetylation. Intravenous administration of LBH589 in immunodeficient BALB/c-RAG2(-/-)γc(-/-) mice in which human-derived T and B-ALL cell lines were injected induced a significant reduction in tumor growth. Using primary ALL cells, a xenograft model of human leukemia in BALB/c-RAG2(-/-)γc(-/-) mice was established, allowing continuous passages of transplanted cells to several mouse generations. Treatment of mice engrafted with T or B-ALL cells with LBH589 induced an in vivo increase in the acetylation of H3 and H4, which was accompanied with prolonged survival of LBH589-treated mice in comparison with those receiving vincristine and dexamethasone. Notably, the therapeutic efficacy of LBH589 was significantly enhanced in combination with vincristine and dexamethasone. Our results show the therapeutic activity of LBH589 in combination with standard chemotherapy in pre-clinical models of ALL and suggest that this combination may be of clinical value in the treatment of patients with ALL.

Angiogenic therapy for cardiac repair based on protein delivery systems.

Cardiovascular diseases remain the first cause of morbidity and mortality in the developed countries and are a major problem not only in the western nations but also in developing countries. Current standard approaches for treating patients with ischemic heart disease include angioplasty or bypass surgery. However, a large number of patients cannot be treated using these procedures. Novel curative approaches under investigation include gene, cell, and protein therapy. This review focuses on potential growth factors for cardiac repair. The role of these growth factors in the angiogenic process and the therapeutic implications are reviewed. Issues including aspects of growth factor delivery are presented in relation to protein stability, dosage, routes, and safety matters. Finally, different approaches for controlled growth factor delivery are discussed as novel protein delivery platforms for cardiac regeneration.

Lipid raft-targeted therapy in multiple myeloma.

Despite recent advances in treatment, multiple myeloma (MM) remains an incurable malignancy. By using in vitro, ex vivo and in vivo approaches, we have identified here that lipid rafts constitute a new target in MM. We have found that the phospholipid ether edelfosine targets and accumulates in MM cell membrane rafts, inducing apoptosis through co-clustering of rafts and death receptors. Raft disruption by cholesterol depletion inhibited drug uptake by tumor cells as well as cell killing. Cholesterol replenishment restored MM cell ability to take up edelfosine and to undergo drug-induced apoptosis. Ceramide addition displaced cholesterol from rafts, and inhibited edelfosine-induced apoptosis. In an MM animal model, edelfosine oral administration showed a potent in vivo antimyeloma activity, and the drug accumulated preferentially and dramatically in the tumor. A decrease in tumor cell cholesterol, a major raft component, inhibited the in vivo antimyeloma action of edelfosine and reduced drug uptake by the tumor. The results reported here provide the proof-of-principle and rationale for further clinical evaluation of edelfosine and for this raft-targeted therapy to improve patient outcome in MM. Our data reveal cholesterol-containing lipid rafts as a novel and efficient therapeutic target in MM, opening a new avenue in cancer treatment.