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Hospital de Órbigo, Spain

Perez-Perarnau A.,University of Barcelona | Coll-Mulet L.,University of Barcelona | Rubio-Patino C.,University of Barcelona | Iglesias-Serret D.,University of Barcelona | And 7 more authors.
Epigenetics | Year: 2011

Histone deacetylases (HDACs) play a key role in the regulation of acetylation status not only of histones but also of many other non-histone proteins involved in cell cycle regulation, differentiation or apoptosis. Therefore, histone deacetylase inhibitors (HDACi) have emerged as promising anticancer agents. Herein, we report the characterization of apoptosis in B-cell chronic lymphocytic leukemia (CLL) induced by two HDACi, Kendine 92 and SAHA. Both inhibitors induce dose-, time- and caspase-dependent apoptosis through the mitochondrial pathway. Interestingly, Kendine 92 and SAHA show a selective cytotoxicity for B lymphocytes and induce apoptosis in CLL cells with mutated or deleted TP53 as effectively as in tumor cells harboring wild-type TP53. The pattern of apoptosis-related gene and protein expression profile has been characterized. It has shown to be irrespective of TP53 status and highly similar between SAHA and Kendine 92 exposure. The balance between the increased BAD, BNIP3L, BNIP3, BIM, PUMA and AIF mRNA expression levels, and decreased expression of BCL-W, BCL-2, BFL-1, XIAP and FLIP indicates global changes in the apoptosis mRNA expression profile consistent with the apoptotic outcome. Protein expression analysis shows increased levels of NOXA, BIM and PUMA proteins upon Kendine 92 and SAHA treatment. Our results highlight the capability of these molecules to induce apoptosis not only in a selective manner but also in those cells frequently resistant to standard treatments. Thus, Kendine 92 is a novel HDACi with anticancer efficacy for non-proliferating CLL cells. © 2011 Landes Bioscience. Source

Santidrian A.F.,University of Barcelona | Gonzalez-Girones D.M.,University of Barcelona | Iglesias-Serret D.,University of Barcelona | Coll-Mulet L.,University of Barcelona | And 12 more authors.
Blood | Year: 2010

5-Aminoimidazole-4-carboxamide riboside or acadesine (AICAR) induces apoptosis in chronic lymphocytic leukemia (CLL) cells. A clinical study of AICAR is currently being performed in patients with this disease. Here, we have analyzed the mechanisms involved in AICAR-induced apoptosis in CLL cells in which it activates its only well-known molecular target, adenosine monophosphate-activated protein kinase (AMPK). However, AMPK activation with phenformin or A-769662 failed to induce apoptosis in CLL cells and AICAR also potently induced apoptosis in B lymphocytes from Ampkα1-/- mice, demonstrating an AMPK-independent mechanism of cell death. Importantly, AICAR induced apoptosis irrespective of the tumor suppressor TP53 or ataxia telangiectasia mutated (ATM) status via induction of the mitochondrial pathway. Apoptosis was preceded by an increase in mRNA and protein levels of proapoptotic BCL-2 family proteins of the BH3-only subgroup, including BIM, NOXA, and PUMA in CLL cells. Strikingly, B lymphocytes from Noxa-/- or Bim -/- mice were partially protected from the cytotoxic effects of AICAR. Consistently, B cells from Noxa-/-/ Bim-/- mice resisted induction of apoptosis by AICAR as potently as B lymphocytes overexpressing transgenic BCL-2. These findings support the notion that AICAR is an interesting alternative therapeutic option for CLL patients with impaired p53 function and resistance to conventional chemotherapy. © 2010 by The American Society of Hematology. Source

Araujo Z.,Central University of Venezuela | Giampietro F.,Central University of Venezuela | Bochichio M.A.,Central University of Venezuela | Palacios A.,Central University of Venezuela | And 12 more authors.
Memorias do Instituto Oswaldo Cruz | Year: 2013

The goal of this study was to demonstrate the usefulness of an enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of pulmonary tuberculosis (PTB) and extrapulmonary TB (EPTB). This assay used 20 amino acid-long, non-overlapped synthetic peptides that spanned the complete Mycobacterium tuberculosis ESAT-6 and Ag85A sequences. The validation cohort consisted of 1,102 individuals who were grouped into the following five diagnostic groups: 455 patients with PTB, 60 patients with EPTB, 40 individuals with non-EPTB, 33 individuals with leprosy and 514 healthy controls. For the PTB group, two ESAT-6 peptides (12033 and 12034) had the highest sensitivity levels of 96.9% and 96.2%, respectively, and an Ag85A-peptide (29878) was the most specific (97.4%) in the PTB groups. For the EPTB group, two Ag85A peptides (11005 and 11006) were observed to have a sensitivity of 98.3% and an Ag85A-peptide (29878) was also the most specific (96.4%). When combinations of peptides were used, such as 12033 and 12034 or 11005 and 11006, 99.5% and 100% sensitivities in the PTB and EPTB groups were observed, respectively. In conclusion, for a cohort that consists entirely of individuals from Venezuela, a multi-antigen immunoassay using highly sensitive ESAT-6 and Ag85A peptides alone and in combination could be used to more rapidly diagnose PTB and EPTB infection. Source

Cosialls A.M.,University of Barcelona | Santidrian A.F.,University of Barcelona | Coll-Mulet L.,University of Barcelona | Coll-Mulet L.,Institute Of Medicina Predictiva I Personalitzada Del Cancer Imppc | And 8 more authors.
Epigenomics | Year: 2012

Aim: To analyze the methylation status of 35 tumor suppressor genes using methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) in chronic lymphocytic leukemia (CLL). Materials & methods: The DNA of 37 samples from patients with CLL, six healthy donors, and Jurkat and Ramos cell lines was analyzed by MS-MLPA. Results: Our results confirm that hypermethylation is a common and not randomly distributed event in CLL, and some genes, such as WT1, CDH13, IGSF4/TSLC1, GATA5, DAPK1 and RARB, are hypermethylated in more than 25% of the analyzed samples. Importantly, MS-MLPA also detected hypermethylation of some genes not reported previously in CLL, and their methylation status was confirmed by bisulfite sequencing. Conclusion: These results indicate that MS-MLPA is a useful technique for the detection of methylation in CLL samples. Selecting CLL-specific methylation targets in order to generate a CLL-specific MS-MLPA probe set could enhance its usefulness as a tool in studies of risk stratification and guiding the best therapeutic decision. © 2012 Future Medicine Ltd. Source

Martinez-Trillos A.,Institute dinvestigacions Biomediques August Pi i Sunyer IDIBAPS | Pinyol M.,Unitat de Genomica | Navarro A.,Unitat de Genomica | Aymerich M.,Institute dinvestigacions Biomediques August Pi i Sunyer IDIBAPS | And 21 more authors.
Blood | Year: 2014

Mutations in Toll-like receptor (TLR ) and myeloid differentiation primary response 88 ( MYD88 ) genes have been found in chronic lymphocytic leukemia (CLL) at low frequency. We analyzed the incidence, clinicobiological characteristics, and outcome of patients with TLR/MYD88 mutations in 587 CLL patients. Twenty-three patients (3.9%) hadmutations, 19 in MYD88 (one with concurrent IRAK1 mutation), 2 TLR2 (one with concomitant TLR6 mutation), 1 IRAK1 , and 1 TLR5. No mutations were found in IRAK2 and IRAK4. TLR/MYD88- mutated CLL overexpressed genes of the nuclear factor κB pathway. Patients with TLR/MYD88 mutations were significantly younger (83% age ≤50 years) than those with no mutations. TLR/MYD88 mutations were the most frequent in youngpatients. Patients with mutated TLR/MYD88 CLLhad a higher frequency of mutated IGHV and low expression of CD38 and ZAP-70. Overall survival (OS) was better in TLR/MYD88-mutated than unmutated patients in the whole series (10-year OS, 100% vs 62%; P = .002), and in the subset of patients age ≤50 years (100% vs 70%; P = .02). In addition, relative OS of TLR/MYD88-mutated patients was similar to that in the age- and gender-matched population. In summary, TLR/MYD88 mutations identify a population of young CLL patients with favorable outcome. © 2014 by The American Society of Hematology. Source

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