Generación de herramientas celulares para validación preclínica de compuestos antitumorales

Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 23-10-2009Bibliogr.: p.117-13

Association of cholesterol and oxysterols in adipose tissue with obesity and metabolic syndrome traits

Adipose tissue stores a substantial amount of body cholesterol in humans. Obesity is associated with decreased concentrations of serum cholesterol. During weight gain, adipose tissue dysfunction might be one of the causes of metabolic syndrome. The aim of this study is to evaluate cholesterol storage and oxidized metabolites in adipose tissue and their relationship with metabolic clinical characteristics

Genetic predictors of weight loss in overweight and obese subjects

The aim of our study was to investigate a large cohort of overweight subjects consuming a homogeneous diet to identify the genetic factors associated with weight loss that could be used as predictive markers in weight loss interventions. We retrospectively recruited subjects (N = 788) aged over 18 years with a Body Mass Index (BMI) between 25 and 40 kg/m(2) who were treated at our lipid unit for at least one year from 2008 to 2016, and we also recruited a control group (168 patients) with normal BMIs. All participants received counselling from a nutritionist that included healthy diet and physical activity recommendations. We genotyped 25 single nucleotide variants (SNVs) in 25 genes that were previously associated with obesity and calculated genetic scores that were derived from 25 SNVs. The risk allele in CADM2 showed a higher frequency in overweight and obese subjects than in controls (p = 0.007). The mean follow-up duration was 5.58 +/- 2.68 years. Subjects with lower genetic scores showed greater weight loss during the follow-up period. The genetic score was the variable that best explained the variations in weight from the baseline. The genetic score explained 2.4% of weight change variance at one year and 1.6% of weight change variance at the end of the follow-up period after adjusting for baseline weight, sex, age and years of follow-up

Effect of bergamot on lipid profile in humans: A systematic review

Dyslipidemia is a well-established modifiable cardiovascular risk. Although statins can reduce LDLc by 50-60%, less than 20% of patients with high risk of CVD achieve LDL targets. The aim of this systematic review is to evaluate the effect of the nutraceutical, bergamot (Citrus bergamia), on lipid parameters in humans. PubMed, Embase, Cochrane Library, and Google Scholar databases were searched for interventional and observational studies investigating the effect of bergamot on lipid profile in humans. This systematic review retrieved a total of 442 studies of which 12 articles fulfilled the eligibility criteria and were included in the qualitative synthesis. Based on data, 75% of studies showed a significant decrease in total cholesterol, triglycerides and LDLc. The decrease in total cholesterol varied from 12.3% to 31.3%, from 7.6% to 40.8% in LDLc and from 11.5% to 39.5% in triglycerides. Eight trials reported HDLc increase after intervention with bergamot. Overall, a dose-dependent and possible synergistic effect when administering with statins can be deducted from these trials. It is essential to point out that studies had heterogeneous designs and scientific quality of studies was quite limited. Promising findings reveal an alternative therapeutic option in dyslipidemia management with bergamot supplementation, especially in subjects with statins intolerance

ABCG5/G8 gene is associated with hypercholesterolemias without mutation in candidate genes and non-cholesterol sterols

Context Approximately 20% to 40% of clinically defined familial hypercholesterolemia (FH) cases do not show a causative mutation in candidate genes (mutation-negative FH), and some of them may have a polygenic origin. Objective The aim of this work was to study the prevalence of ABCG5/G8 genetic variants in mutation-negative FH, as defects in these genes relate to intestinal hyperabsorption of cholesterol and thus ABCG5/G8 variants could explain in part the mechanism of hypercholesterolemia. Design, setting, and patients We sequenced the ABCG5/G8 genes in 214 mutation-negative FH and 97 controls. Surrogate markers of cholesterol absorption (5?-cholestanol, ?-sitosterol, campesterol, stigmasterol, and sitostanol) were quantified by high-performance liquid chromatography?tandem mass spectrometry in both studied groups. Results We found 8 mutation-negative FH patients (3.73%) with a pathogenic mutation in ABCG5/G8 genes. We observed significantly higher concentration of surrogate markers of cholesterol absorption in mutation-negative FH than in controls. In addition, we found significantly higher concentrations of cholesterol absorption markers in mutation-negative FH with ABCG5/G8 defects than in mutation-negative, ABCG5/G8-negative FH. A gene score reflecting the number of common single nucleotide variants associated with hypercholesterolemia was significantly higher in cases than in controls (P = .032). Subjects with a gene score above the mean had significantly higher 5?-cholestanol and stigmasterol than those with a lower gene score. Conclusions Mutation-negative FH subjects accumulate an excess of rare and common gene variations in ABCG5/G8 genes. This variation is associated with increased intestinal absorption of cholesterol, as determined by surrogate makers, suggesting that these loci contribute to hypercholesterolemia by enhancing intestinal cholesterol absorption.This study was supported by grants from the Spanish Ministry of Economy and Competitiveness PI15/01983, PI13/02507, PI12/01321, CIBERCV, CIBEROBN, and Cuenca Villoro Foundation. These projects are co-financed by Instituto de Salud Carlos III and the European Regional Development Fund (ERDF) of the European Union “A way to make Europe.

New interfacial microtubule inhibitors of marine origin, PM050489/PM060184, with potent antitumor activity and a distinct mechanism

We have investigated the target and mechanism of action of a new family of cytotoxic small molecules of marine origin. PM050489 and its dechlorinated analogue PM060184 inhibit the growth of relevant cancer cell lines at subnanomolar concentrations. We found that they are highly potent microtubule inhibitors that impair mitosis with a distinct molecular mechanism. They bind with nanomolar affinity to unassembled αβ-tubulin dimers, and PM050489 binding is inhibited by known Vinca domain ligands. NMR TR-NOESY data indicated that a hydroxyl-containing analogue, PM060327, binds in an extended conformation, and STD results define its binding epitopes. Distinctly from vinblastine, these ligands only weakly induce tubulin self-association, in a manner more reminiscent of isohomohalichondrin B than of eribulin. PM050489, possibly acting like a hinge at the association interface between tubulin heterodimers, reshapes Mg2+-induced 42 S tubulin double rings into smaller 19 S single rings made of 7 ± 1 αβ-tubulin dimers. PM060184-resistant mutants of Aspergillus nidulans map to β-tubulin Asn100, suggesting a new binding site different from that of vinblastine at the associating β-tubulin end. Inhibition of assembly dynamics by a few ligand molecules at the microtubule plus end would explain the antitumor activity of these compounds, of which PM060184 is undergoing clinical trials.We wish to thank J. M. Fernandez Sousa (PharmaMar) for useful discussions and support, E. Hamel (NCI) for providing eribulin, C. Scazzocchio and G. Diallinas for useful advice on mutant screening, H. N. Arst for advice on mutant screening and mapping and for kindly providing strains MAD3688 and MAD4655, T. J. Fitzgerald (A&M University) for MTC and C. Alfonso (CIB) for AUC analysis. We also thank Rhône Poulenc Rorer Aventis for supplying docetaxel and Matadero Municipal Vicente de Lucas de Segovia for providing the calf brains for tubulin purification. B.P. had a contract from Comunidad de Madrid, and A.C. had a Ramon y Cajal contract, J.R.-S. had a fellowship from “Programa de Cooperación Científica entre el Ministerio de Ciencia, Tecnologías y Medio Ambiente de la República de Cuba (CITMA) y el CSIC”. This work was supported by grants BIO2010-16351 (J.F.D.), BQU2009-08536 (J.J.-B.), CAM S2010/BMD-2457 (J.F.D.), CAM S2010/BMD-2353 (J.J.-B., J.M.A.), IPT-2011-0752-900000 and BIO2012-30965 (M.A.P.), BFU2011-23416 (J.M.A.) and PharmaMar-CSIC contracts

Irvalec Inserts into the Plasma Membrane Causing Rapid Loss of Integrity and Necrotic Cell Death in Tumor Cells

Irvalec is a marine-derived antitumor agent currently undergoing phase II clinical trials. In vitro, Irvalec induces a rapid loss of membrane integrity in tumor cells, accompanied of a significant Ca2+ influx, perturbations of membrane conductivity, severe swelling and the formation of giant membranous vesicles. All these effects are not observed in Irvalec-resistant cells, or are significantly delayed by pretreating the cells with Zn2+. Using fluorescent derivatives of Irvalec it was demonstrated that the compound rapidly interacts with the plasma membrane of tumor cells promoting lipid bilayer restructuration. Also, FRET experiments demonstrated that Irvalec molecules localize in the cell membrane close enough to each other as to suggest that the compound could self-organize, forming supramolecular structures that likely trigger cell death by necrosis through the disruption of membrane integrity

PDGFR-α en tant que marqueur de réponse pour le traitement avec PM00104

70 páginas, 12 figuras, 5 tablas. Fecha de solicitud internacional: 22/10/2010; Fecha de prioridad 22/10/2009. IPC: C12Q 1/68; A61K 31/015. Solicitantes: Pharma Mar, S. A.[EN] The present invention relates to use of PM00104 in the treatment of cancer in patients having tumors with certain molecular markers profile, in particular, having low PDGFR-α expression levels. The invention also relates to methods for providing personalized PM00104 chemotherapy to cancer patients based on said tumor molecular markers.[FR] La présente invention concerne l'utilisation de PM00104 dans le traitement du cancer chez des patients ayant des tumeurs ayant un certain profil de marqueurs moléculaires, en particulier, ayant de faibles taux d'expression de PDGFR-α. L'invention concerne en outre des procédés pour produire une chimiothérapie personnalisée avec PM00104 de patients cancéreux basée sur lesdits marqueurs moléculaires de tumeur.Peer reviewe