BackgroundFragile X Syndrome (FXS) is the second cause of intellectual disability after Down syndrome and the most prevalent cause of intellectual disability in males, affecting 1:5000–7000 men and 1:4000–6000 women. It is caused by an alteration of the FMR1 gene, which maps at the Xq27.3 band: more than 99% of individuals have a CGG expansion (>200 triplets) in the 5′ UTR of the gene, and FMR1 mutations and duplication/deletion are responsible for the remaining (<1%) molecular diagnoses of FXS. The aim of this review was to gather the current clinical and molecular knowledge about FXS to provide clinicians with a tool to guide the initial assessment and follow-up of FXS and to offer to laboratory workers and researchers an update about the current diagnostic procedures.DiscussionFXS is a well-known condition; however, most of the studies thus far have focused on neuropsychiatric features. Unfortunately, some of the available studies have limitations, such as the paucity of patients enrolled or bias due to the collection of the data in a single-country population, which may be not representative of the average global FXS population. In recent years, insight into the adult presentation of the disease has progressively increased. Pharmacological treatment of FXS is essentially symptom based, but the growing understanding of the molecular and biological mechanisms of the disease are paving the way to targeted therapy, which may reverse the effects of FMRP deficiency and be a real cure for the disease itself, not just its symptoms.ConclusionsThe clinical spectrum of FXS is wide, presenting not only as an isolated intellectual disability but as a multi-systemic condition, involving predominantly the central nervous system but potentially affecting any apparatus. Given the relative high frequency of the condition and its complex clinical management, FXS appears to have an important economic and social burden.

The role of epigenetics in the modulation of longevity has not been studied in humans. To this aim, (1) we evaluated the DNA methylation from peripheral leukocytes of 21 female centenarians, their 21 female offspring, 21 offspring of both non-long-lived parents, and 21 young women through ELISA assay, pyrosequencing analysis of Alu sequences, and quantification of methylation in CpG repeats outside CpG AGE (2013) 35:1961-1973 DOI 10.1007 islands; (2) we compared the DNA methylation profiles of these populations through Infinium array for genome-wide CpG methylation analysis. We observed an age-related decrease in global DNA methylation and a delay of this process in centenarians' offspring. Interestingly, literature data suggest a link between the loss of DNA methylation observed during aging and the development of age-associated diseases. Genomewide methylation analysis evidenced DNA methylation profiles specific for aging and longevity: (1) aging-associated DNA hypermethylation occurs predominantly in genes involved in the development of anatomical structures, organs, and multicellular organisms and in the regulation of transcription; (2) genes involved in nucleotide biosynthesis, metabolism, and control of signal transmission are differently methylated between centenarians' offspring and offspring of both non-long-lived parents, hypothesizing a role for these genes in human longevity. Our results suggest that a better preservation of DNA methylation status, a slower cell growing/metabolism, and a better control in signal transmission through epigenetic mechanisms may be involved in the process of human longevity. These data fit well with the observations related to the beneficial effects of mild hypothyroidism and insulinlike growth factor I system impairment on the modulation of human lifespan.

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(2015) Mesenchymal stem cells: potential for therapy and treatment of chronic non-healing skin wounds, Organogenesis, 11:4, 183-206, DOI: 10.1080/15476278.2015 ABSTRACT. Wound healing is a complex physiological process including overlapping phases (hemostatic/inflammatory, proliferating and remodeling phases). Every alteration in this mechanism might lead to pathological conditions of different medical relevance. Treatments for chronic nonhealing wounds are expensive because reiterative treatments are needed. Regenerative medicine and in particular mesenchymal stem cells approach is emerging as new potential clinical application in wound healing. In the past decades, advance in the understanding of molecular mechanisms underlying wound healing process has led to extensive topical administration of growth factors as part of wound care. Currently, no definitive treatment is available and the research on optimal wound care depends upon the efficacy and cost-benefit of emerging therapies.Here we provide an overview on the novel approaches through stem cell therapy to improve cutaneous wound healing, with a focus on diabetic wounds and Systemic Sclerosis-associated ulcers, which are particularly challenging. Current and future treatment approaches are discussed with an emphasis on recent advances.

Intestinal-type adenocarcinoma (ITAC) of the nasal cavity and paranasal sinuses is an uncommon tumor associated with occupational exposure to dusts of different origin. Few investigations addressed molecular alterations in ITAC mainly focused on TP53, K-ras and H-ras gene mutations. The occurrence of TP53, p14 ARF Intestinal-type adenocarcinoma (ITAC) of the nasal cavity and paranasal sinuses is an uncommon, professional-related tumor characterized by high local aggressiveness and ominous outcome. 1 ITAC encompasses a neoplasm group showing a range of microscopic features spanning from tumors indistinguishable from typical colonic adenocarcinoma to colloid or signet-ring cell carcinoma of the colon. 2 Surgery is, and still remains, the treatment of choice for this tumor although it has been complemented recently by primary chemotherapy. 3 ITAC clearly predominates among males and exhibits an extreme gender distribution likely to be related to an occupational exposure. Several epidemiologic studies pointed out the association of ITAC with professional exposure primarily to wood or leather dust. 4 -8 Dusts of different origin are other potential risk factors for sinonasal adenocarcinomas, including textile, 9,10 cereal or cement dust. 11 The close relationship between professional exposure and ITAC strongly suggests that dusts and chemical elements may be implicated as etiological agents in the tumorigenesis of this tumor. Investigations into the genotoxic action of several substances present in the wood or used by wood-and leather-workers showed the combined genotoxic effects of dusts and chemicals. 7,8 A variety of chemical carcinogens cause mutations in human tumors by forming covalent adducts that increase the probability of errors during DNA replication. 12 Some carcinogenic agents may target oncogenes and tumor suppressor genes producing specific types and locations of DNA alterations. These carcinogen-induced mutational spectra are influenced by the specific DNA sequence. 13 Previous studies showed that methylated CpG dinucleotides may represent preferential targets for mutagens. 14,15 A strong and selective formation of both adducts and mutations involving CpG islands of the TP53 gene is frequent in human tumors 16,17 and an association between DNA methylation and exposure to carcinogens, as tobacco 18 and vinyl chloride 19 has been reported recently.In addition, loss of heterozygosity (LOH) at chromosomal loci encoding the TP53, p14 ARF and p16 INK4a genes represents a further molecular event related to carcinogenic exposure, as found in tobacco smoke-associated larynx cancer. 20 Moreover, TP53 mutations and p16INK4a deletion or hypermethylation correlate with early genetic changes in malignancy development of the Barrett's esophagus 21,22 and frequently occur as late events in colorectal adenocarcinoma. [23][24][25] Few investigators addressed molecular alterations in ITACs. In the assumption that morphologic resemblance with colorectal cancer might reflect equivalent genetic alterations, Wu et al. 26 ...

BackgroundMultiple (epi)genetic defects affecting the expression of the imprinted genes within the 11p15.5 chromosomal region underlie Silver–Russell (SRS) and Beckwith–Wiedemann (BWS) syndromes. The molecular diagnosis of these opposite growth disorders requires a multi-approach flowchart to disclose known primary and secondary (epi)genetic alterations; however, up to 20 and 30 % of clinically diagnosed BWS and SRS cases remain without molecular diagnosis. The complex structure of the 11p15 region with variable CpG methylation and low-rate mosaicism may account for missed diagnoses. Here, we demonstrate the relevance of complementary techniques for the assessment of different CpGs and the importance of testing multiple tissues to increase the SRS and BWS detection rate.ResultsMolecular testing of 147 and 450 clinically diagnosed SRS and BWS cases provided diagnosis in 34 SRS and 185 BWS patients, with 9 SRS and 21 BWS cases remaining undiagnosed and herein referred to as “borderline.” A flowchart including complementary techniques and, when applicable, the analysis of buccal swabs, allowed confirmation of the molecular diagnosis in all borderline cases. Comparison of methylation levels by methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) in borderline and control cases defined an interval of H19/IGF2:IG-DMR loss of methylation that was distinct between “easy to diagnose” and “borderline” cases, which were characterized by values ≤mean −3 standard deviations (SDs) compared to controls. Values ≥mean +1 SD at H19/IGF2: IG-DMR were assigned to borderline hypermethylated BWS cases and those ≤mean −2 SD at KCNQ1OT1: TSS-DMR to hypomethylated BWS cases; these were supported by quantitative pyrosequencing or Southern blot analysis. Six BWS cases suspected to carry mosaic paternal uniparental disomy of chromosome 11 were confirmed by SNP array, which detected mosaicism till 10 %. Regarding the clinical presentation, borderline SRS were representative of the syndromic phenotype, with exception of one patient, whereas BWS cases showed low frequency of the most common features except hemihyperplasia.ConclusionsA conclusive molecular diagnosis was reached in borderline methylation cases, increasing the detection rate by 6 % for SRS and 5 % for BWS cases. The introduction of complementary techniques and additional tissue analyses into routine diagnostic work-up should facilitate the identification of cases undiagnosed because of mosaicism, a distinctive feature of epigenetic disorders.Electronic supplementary materialThe online version of this article (doi:10.1186/s13148-016-0183-8) contains supplementary material, which is available to authorized users.

A role of X chromosome inactivation process in the development of breast cancer have been suggested. In particular, the relationship between the breast cancer predisposing gene BRCA1 and XIST, the main mediator of X chromosome inactivation, has been intensely investigated, but still remains controversial. We investigated this topic by assessing XIST behaviour in different groups of breast carcinomas and in a panel of breast cancer cell lines both BRCA1 mutant and wild type. In addition, we evaluated the occurrence of broader defects of heterochromatin in relation to BRCA1 status in breast cancer cells. We provide evidence that in breast cancer cells BRCA1 is involved in XIST regulation on the active X chromosome, but not in its localization as previously suggested, and that XIST can be unusually expressed by an active X and can decorate it. This indicates that the detection of XIST cloud in cancer cell is not synonymous of the presence of an inactive X chromosome. Moreover, we show that global heterochromatin defects observed in breast tumor cells are independent of BRCA1 status. Our observations sheds light on a possible previously uncharacterized mechanism of breast carcinogenesis mediated by XIST misbehaviour, particularly in BRCA1-related cancers. Moreover, the significant higher levels of XIST-RNA detected in BRCA1-associated respect to sporadic basal-like cancers, opens the possibility to use XIST expression as a marker to discriminate between the two groups of tumors.

Cellular cholesterol uptake is mainly mediated by the LDL receptor (LDL-R) and the scavenger receptor family. We hypothesized that expression levels of key receptors of these families were regulated differently in placentas from IUGR pregnancies with varying degrees of severity. Third-trimester placentas from IUGR pregnancies with (IUGR-S) and without (IUGR-M) fetal hemodynamic changes and from control (AGA) pregnancies were studied. LDL-R, LDL-Rrelated protein (LRP-1), and scavenger receptor class B type I (SR-BI) mRNA and protein levels were measured. Cholesterol concentration and composition of lipoproteins were analyzed enzymatically and by lipid electrophoresis, respectively, in maternal and umbilical cord blood. LDL-R mRNA levels in IUGR-M were similar to AGA but lower (P Ͻ 0.05) in IUGR-S. In contrast, LDL-R protein was twofold (IUGR-M) and 1.8-fold (IUGR-S) higher (P Ͻ 0.05) than in the AGA group. LRP-1 mRNA and protein levels were not altered in the IUGR cases. SR-BI mRNA was unchanged in IUGR, but protein levels were lower (P Ͻ 0.05) in IUGR-S than in the other groups. Maternal plasma concentrations of LDL cholesterol were higher (P Ͻ 0.05) in the AGA group (188.5 Ϯ 23.6 mg/dl) than in the IUGR-S group (154.2 Ϯ 26.1). Electrophoretic mobility of the LDL fraction in maternal plasma demonstrated significant changes in migration toward higher values (AGA 0.95 Ϯ 0.06, IUGR-M 1.12 Ϯ 0.11, P Ͻ 0.001; IUGR-S 1.28 Ϯ 0.20, P ϭ 0.002). We conclude that LDL-R and SR-BI levels are altered in IUGR pregnancies. These differences were associated with changes in LDL, but not HDL, mobility and cholesterol concentration in maternal circulation. pregnancy; placenta; lipids; fetal growth CHOLESTEROL HAS MULTIPLE BIOLOGICAL ROLES that include its functioning as a structural membrane component, precursor for steroid synthesis, and activator of various cellular processes (42). Extensive steroid hormone synthesis in the placenta and the rapid growth and development of the fetus make pregnancy a condition of high cholesterol demand in the feto-placental unit (23). In humans, both placental tissue (39) and fetal organs (5) have the capacity for de novo cholesterol synthesis. However, the high cholesterol demand in the fetal tissues may not be fully satisfied by endogenous means. A significantly higher cholesterol concentration in the umbilical vein compared with the arteries (33) suggests transfer from maternal or placental sources to the fetus. In the third trimester of gestation, maternally-derived cholesterol reportedly contributes ϳ22-40% to the fetal cholesterol pool (14, 24). However, this remains controversial (25). The molecular mechanisms accounting for the uptake of maternal cholesterol into the placenta, mainly as lipoprotein-associated cholesterol (42), and for subsequent transfer, if any, into the fetal circulation, are as yet poorly understood.Cellular uptake of maternal low-density lipoprotein (LDL), high-density lipoprotein (HDL), and very low-density lipoprotein (VLDL) is mainly mediated by two receptor familie...