Guerrero D.,Biomedical Research Center |
Guarch R.,Navarra Hospital Complex |
Ojer A.,Biomedical Research Center |
Casas J.M.,Hospital Complex of Navarra |
And 5 more authors.
International Journal of Cancer | Year: 2011
Squamous cell carcinoma (SCC) of the vulva is a heterogeneous disease, associated or not with vulvar lichen sclerosus (LS). The precursor role of LS in vulvar cancer is unclear. We studied the epigenetic alterations of RASSF1A, RASSF2A, p16, TSP-1 and MGMT genes in vulvar SCCs, LS associated with SCC, isolated LS and normal vulvar skin. Gene hypermethylation and human papillomavirus presence were evaluated by methylation-specific PCR and PCR/reverse line blot, respectively. High-risk human papillomavirus types were present in 16.7% of the patients with vulvar SCC. There were increasing percentages of hypermethylation of genes from isolated LS to LS associated with vulvar SCC and vulvar SCC. The genes were hypermethylated more frequently in vulvar SCC associated with LS than in those not associated with LS, MGMT and RASSF2A being unmethylated in LS not associated with vulvar SCC. TSP-1 hypermethylation was related to recurrence in patients with vulvar cancer. Conclusions are as follows: (i) the epigenetic inactivation of genes is a common event in vulvar SCC and is also present in adjacent lesions, implying a possible precursor role for these alterations; (ii) MGMT and RASSF2A hypermethylation are present exclusively in vulvar SCC and LS associated with SCC, and absent from isolated LS; and (iii) TSP-1 hypermethylation is a bad prognosis factor in vulvar SCC. © 2010 UICC. Source
Bens S.,Institute of Human Genetics |
Bens S.,University of Kiel |
Ammerpohl O.,Institute of Human Genetics |
Martin-Subero J.I.,Institute of Human Genetics |
And 8 more authors.
Sexual Development | Year: 2011
Male external genital differentiation is accompanied by implementation of a long-term, male-specific gene expression pattern indicating androgen programming in cultured genital fibroblasts. We hypothesized the existence of an epigenetic background contributing to this phenomenon. DNA methylation levels in 2 normal scrotal fibroblast strains from 46,XY males compared to 2 labia majora fibroblast strains from 46,XY females with complete androgen insensitivity syndrome (AIS) due to androgen receptor (AR) mutations were analyzed by Illumina GoldenGate methylation arrays®. Results were validated with pyrosequencing in labia majora fibroblast strains from fifteen 46,XY patients and compared to nine normal male scrotal fibroblast strains. HOXA5 showed a significantly higher methylation level in complete AIS. This finding was confirmed by bisulfite pyrosequencing of 14 CpG positions within the HOXA5 promoter in the same strains. Extension of the 2 groups revealed a constant low HOXA5 methylation pattern in the controls in contrast to a highly variable methylation pattern in the AIS patients. HOXA5 represents a candidate gene of androgen-mediated promoter methylation. The constantly low HOXA5 DNA methylation level of normal male scrotal fibroblast strains and the frequently high methylation levels in labia majora fibroblast strains in AIS indicate for the first time that androgen programming in sexual differentiation is not restricted to global gene transcription but also occurs at the epigenetic level. Copyright © 2011 S. Karger AG, Basel. Source
Moore G.E.,University College London |
Ishida M.,University College London |
Demetriou C.,University College London |
Al-Olabi L.,University College London |
And 21 more authors.
Philosophical Transactions of the Royal Society B: Biological Sciences | Year: 2015
Identifying the genetic input for fetal growth will help to understand common, serious complications of pregnancy such as fetal growth restriction. Genomic imprinting is an epigenetic process that silences one parental allele, resulting in monoallelic expression. Imprinted genes are important in mammalian fetal growth and development. Evidence has emerged showing that genes that are paternally expressed promote fetal growth, whereas maternally expressed genes suppress growth. We have assessed whether the expression levels of key imprinted genes correlate with fetal growth parameters during pregnancy, either early in gestation, using chorionic villus samples (CVS), or in term placenta. We have found that the expression of paternally expressing insulinlike growth factor 2 (IGF2), its receptor IGF2R, and the IGF2/IGF1R ratio in CVS tissues significantly correlate with crown–rump length and birthweight, whereas term placenta expression shows no correlation. For the maternally expressing pleckstrin homology-like domain family A, member 2 (PHLDA2), there is no correlation early in pregnancy in CVS but a highly significant negative relationship in term placenta. Analysis of the control of imprinted expression of PHLDA2 gave rise to a maternally and compounded grandmaternally controlled genetic effect with a birthweight increase of 93/155 g, respectively, when one copy of the PHLDA2 promoter variant is inherited. Expression of the growth factor receptor-bound protein 10 (GRB10) in termplacenta is significantly negatively correlated with head circumference. Analysis of the paternally expressing delta-like 1 homologue (DLK1) showsthat the paternal transmission of type 1 diabetes protective G allele of rs941576 single nucleotide polymorphism (SNP) results in significantly reduced birth weight (2132 g). In conclusion, we have found that the expression of key imprinted genes show a strong correlation with fetal growth and that for both genetic and genomics data analyses, it is important not to overlook parent-of-origin effects. © 2015 The Author(s) Published by the Royal Society. All rights reserved. Source
Ishida M.,University College London |
Monk D.,University College London |
Monk D.,Bellvitge Institute for Biomedical Research |
Duncan A.J.,University College London |
And 9 more authors.
American Journal of Human Genetics | Year: 2012
Birth weight is an important indicator of both perinatal and adult health, but little is known about the genetic factors contributing to its variability. Intrauterine growth restriction is a leading cause of perinatal morbidity and mortality and is also associated with adult disease. A significant correlation has been reported between lower birth weight and increased expression of the maternal PHLDA2 allele in term placenta (the normal imprinting pattern was maintained). However, a mechanism that explains the transcriptional regulation of PHLDA2 on in utero growth has yet to be described. In this study, we sequenced the PHLDA2 promoter region in 263 fetal DNA samples to identify polymorphic variants. We used a luciferase reporter assay to identify in the PHLDA2 promoter a 15 bp repeat sequence (RS1) variant that significantly reduces PHLDA2-promoter efficiency. RS1 genotyping was then performed in three independent white European normal birth cohorts. Meta-analysis of all three (total n = 9,433) showed that maternal inheritance of RS1 resulted in a significant 93 g increase in birth weight (p = 0.01; 95% confidence interval [CI] = 22-163). Moreover, when the mother was homozygous for RS1, the influence on birth weight was 155 g (p = 0.04; 95% CI = 9-300), which is a similar magnitude to the reduction in birth weight caused by maternal smoking. © 2012 The American Society of Human Genetics. Source
Videira M.,Imedul Research Institute For Medicines And Pharmaceutical Science |
Almeida A.J.,Imedul Research Institute For Medicines And Pharmaceutical Science |
Fabra T.,Bellvitge Institute for Biomedical Research
Nanomedicine: Nanotechnology, Biology, and Medicine | Year: 2012
Lung cancer remains a leading cause of death due to the low efficacy of chemotherapy, mainly related to the administration route used. Therefore, alternative administration routes are needed. Paclitaxel (PTX) is an insoluble anticancer drug active against solid tumors, such as those found in lung cancer, that has stimulated an intense research effort over recent years. Solid lipid nanoparticles (SLNs) are potential carriers for poorly soluble drugs, being biodegradable systems that served as alternatives to the usual colloidal carriers. That system was used to deliver PTX to the lungs and seem to fulfill the requirements for an optimum particulate carrier. Furthermore, PTX-loaded SLN pulmonary administration provided a target administration, which is expected to avoid high concentration of the drug at nontarget tissues, reducing toxicity, and increasing the drug's therapeutic index. The rationale of this study was to deliver a colloidal system to the lung lymphatics through a pulmonary route for cancer therapy. From the Clinical Editor: Paclitaxel-loaded solid lipid nanoparticles were used to target tumors in a murine lung cancer model enabling high PTX concentration in the target with reduced systemic toxicity and increased therapeutic index. © 2012 Elsevier Inc. Source