[Show abstract][Hide abstract] ABSTRACT: Studies on individual types of gynecological cancers (GCs), utilizing novel expression technologies, have revealed specific pathogenetic patterns and gene markers for cervical (CC), endometrial (EC) and vulvar cancer (VC). Although the clinical phenotypes of the three types of gynecological cancers are discrete, the fact they originate from a common embryological origin, has led to the hypothesis that they might share common features reflecting regression to early embryogenesis. To address this question, we performed a comprehensive comparative analysis of their profiles. Our data identified both common features (pathways and networks) and novel distinct modules controlling the same deregulated biological processes in all three types. Specifically, four novel transcriptional modules were discovered regulating cell cycle and apoptosis. Integration and comparison of our data with other databases, led to the identification of common features among cancer types, embryonic stem (ES) cells and the newly discovered cell population of squamocolumnar (SC) junction of the cervix, considered to host the early cancer events. Conclusively, these data lead us to propose the presence of common features among gynecological cancers, other types of cancers, ES cells and the pre-malignant SC junction cells, where the novel E2F/NFY and MAX/CEBP modules play an important role for the pathogenesis of gynecological carcinomas.
[Show abstract][Hide abstract] ABSTRACT: Mucosal melanomas exhibit discrete genetic features compared to cutaneous melanoma. Limited studies on gynecological melanomas revealed significant heterogeneity and low mutational burden. To gain further insight into their genetics and DNA repair efficiency, we systematically investigated the status of eight genes whose products are critically involved in the MAPK/ERK, PI3K/AKT, and GNAQ/11 pathways, including BRAF, NRAS, HRAS, KRAS, c-KIT, PI3K, GNAQ, and GNA11, in a series of 16 primary gynecological melanomas, covering all anatomical locations, ranging from stages I to III. Analysis either by real-time PCR coupled with fluorescence melting curve analysis or by PCR followed by direct sequencing, along with studies for DNA mismatch repair status using immunohistochemistry, disclosed that 15 out of the 16 cases displayed wild-type genotypes, with a single case of vulvar primary melanoma, harboring the activating mutation BRAF(V600E). Investigations on whether this could reflect partly an efficient mismatch repair (MMR) mechanism were confirmed by normal expression of hMLH1 and hMSH2, suggesting that the lack of mutations could be explained by the operation of alternative pathogenetic mechanisms modulating downstream effectors of the signaling pathways. Our data suggest the presence of additional genetic components and provide the impetus for systematic approaches to reveal these yet unidentified genetic parameters.
Full-text · Article · Jan 2015 · BioMed Research International
[Show abstract][Hide abstract] ABSTRACT: Gene therapy refers to the use of DNA or of any other type of nucleic acid, as a pharmaceutical agent to treat a disease. This therapeutic approach was initially designed to treat several monogenic diseases, and is especially suited for the treatment of blood diseases such as hemoglobinopathies or immunodeficiencies. However, the advances in understanding the molecular basis of myocardial dysfunction, the identification and characterization of the properties and plasticity of several subpopulations of cardiac cells, combined with the development of increasingly efficient gene transfer technologies, has rendered heart failure another excellent candidate for gene-based therapies. Moreover, there is still a critical need to further explore novel therapeutic approaches in heart failure, and thus, gene therapy has emerged as a realistic alternative. Particularly, cardiovascular gene therapy has benefitted from recent advancements in vector technology and delivery modalities, and stem cell biology. This chapter reviews the available gene transfer technologies and the molecular features that constitute the main targets in the field of cardiac gene therapy, it presents the current status of gene therapy for the heart, and discusses how the knowledge gained from the initial clinical trials can be used to develop a safer and more efficient gene transfer approach. Since the first demonstration of the in vivo gene transfer into myocardium, there have been a series of advancements that have transformed gene therapy from an experimental tool to the threshold of becoming a viable clinical option.
[Show abstract][Hide abstract] ABSTRACT: Gene therapy utilizing lentiviral-vectors (LVs) is postulated as a dynamic therapeutic alternative for monogenic diseases. However, retroviral gene transfer may cause insertional mutagenesis. Although, such risks had been originally estimated as extremely low, several reports of leukemias or clonal dominance, have led to a re-evaluation of the mechanisms operating in insertional mutagenesis. Therefore, unraveling the mechanism of retroviral integration is mandatory towards safer gene therapy applications. In the present study, we undertook an experimental approach which enabled direct correlation of the cell cycle stage of the target cell with the integration profile of LVs. CD34(+) cells arrested at different stages of cell cycle, were transduced with a GFP-LV. LAM-PCR was employed for integration site detection, followed by microarray analysis to correlate transcribed genes with integration sites. The results indicate that approximately 10% of integration events occurred in actively transcribed genes and that the cell cycle stage of target cells affects integration pattern. Specifically, use of thymine promoted a safer profile, since it significantly reduced integration within cell cycle-related genes, while we observed increased possibility for integration into genes related to development, and decreased possibility for integration within cell cycle and cancer-related genes, when transduction occurs during mitosis.Molecular Therapy (2014); doi:10.1038/mt.2014.246.
No preview · Article · Dec 2014 · Molecular Therapy
[Show abstract][Hide abstract] ABSTRACT: Background/aim:
The basic role of vascular endothelial growth factor (VEGF) in cancer is underscored by the approval of bevacizumab for first-line treatment of cancer patients. Recent anticancer therapeutics based on active tumor targeting by conjugating tumor-specific antibodies has become of great interest in oncology. Current progress in nanomedicine has exploited the possibility of designing tumor-targeted nanocarriers able to deliver specific molecule payloads in a selective manner to improve the efficacy and safety of cancer imaging and therapy. We herein aimed to determine the targeting ability of bevacizumab-conjugated quantum dots (QDs) in vitro and in vivo.
Materials and methods:
We used QDs labeled with bevacizumab, in various in vitro experiments using cell lines derived from colorectal cancer (CRC) and breast cancer (BC). For a competition study of QD-bevacizumab complex and bevacizumab, the cells were pre-treated with bevacizumab (100 nmol/L) for 24 h before exposure to the QD-bevacizumab complex. The breast cancer cells (MDA-MB-231) were injected to 9 nude mice to make the xenograft tumor model. The QD-bevacizumab complex was injected into the tumor model and fluorescence measurements were performed at 1, 12, and 24 h post-injection.
Immunocytochemical data confirmed strong and specific binding of the QD-bevacizumab complex to the cell lines. The cells pre-treated with an excess of bevacizumab showed absence of QD binding. The in vivo fluorescence image disclosed that there was an increased signal of tumor after the injection of QDs. Ex vivo analysis showed 3.1 ± 0.8%, 28.6 ± 5.4% and 30.8 ± 4.2% injected dose/g accumulated in the tumors at 1, 12 and 24 h respectively. Tumor uptake was significantly decreased in the animals pretreated with excess of bevacizumab (p=0.001).
In conclusion, we could successfully detect the VEGF-expressing tumors using QDs-bevacizumab nanoprobes in vitro and in vivo, opening new perspectives for VEGF-targeted non-invasive imaging in clinical practice.
No preview · Article · Nov 2014 · In vivo (Athens, Greece)
[Show abstract][Hide abstract] ABSTRACT: Background:
In this study, we conducted the genotyping of D326Y in COL4A3 and M1327V, as well as F1644F in COL4A4 polymorphisms, in a case-control sample panel of Greek origin population.
Materials and methods:
A case-control panel, with 45 keratoconus (KC) patients and 78 healthy controls, were surveyed. DNA from each individual was tested for the D326Y in COL4A3 and M1327V, as well as F1644F in COL4A4 polymorphisms by direct sequencing.
When analyzing the Hardy-Weinberg equilibrium, we observed no significant deviation from expected numbers in both KC patients and controls. The genotype frequencies in the polymorphisms tested were not found to be significantly associated with KC development risk. The M1327V AA and F1644F TT genotypes were significantly over-represented in healthy individuals.
We could hypothesize that mutations in COL4A3 and COL4A4 genes are not involved in KC risk in Greek population. Nevertheless, the M1327V AA and F1644F TT genotypes were significantly over-represented in healthy individuals, suggesting a protective role of these genotypes in KC development risk in our population.
Full-text · Article · Aug 2014 · Ophthalmic Genetics
[Show abstract][Hide abstract] ABSTRACT: Numerous studies have shown the presence of high levels of growth factors during the process of healing. Growth factors act by binding to the cell surface receptors and contribute to the subsequent activation of signal transduction mechanisms. Wound healing requires a complex of biological and molecular events that includes attraction and proliferation of different type of cells to the wound site, differentiation and angiogenesis. More specifically, migration of various cell types, such as endothelial cells and their precursors, mesenchymal stem/stromal cells (MSCs) or skin fibroblasts (DFs) plays an important role in the healing process. In recent years, the application of platelet rich plasma (PRP) to surgical wounds and skin ulcerations is becoming more frequent, as it is believed to accelerate the healing process. The local enrichment of growth factors at the wound after PRP application causes a stimulation of tissue regeneration. Herein, we studied: (i) the effect of autologous PRP in skin ulcers of patients of different aetiology, (ii) the proteomic profile of PRP, (iii) the migration potential of amniotic fluid MSCs and DFs in the presence of PRP extract in vitro, (iv) the use of the PRP extract as a substitute for serum in cultivating AF-MSCs. Considering its easy access, PRP may provide a valuable tool in multiple therapeutic approaches.
Full-text · Article · Feb 2014 · Stem cell reviews
[Show abstract][Hide abstract] ABSTRACT: To address the value of qRT-PCR and IHC in accurately detecting lymph node micrometastasis in gynecological cancer, we performed a systematic approach, using a set of dual molecular tumor-specific markers such as cytokeratin 19 (CK19) and carbonic anhydrase 9 (CA9), in a series of 46 patients (19 with cervical cancer, 18 with endometrial cancer, and 9 with vulvar cancer). A total of 1281 lymph nodes were analyzed and 28 were found positive by histopathology. Following this documentation, 82 lymph nodes, 11 positive and 71 negative, were randomly selected and further analyzed both by IHC and qRT-PCR for CK19 and CA9 expression. All 11 (100%) expressed CK19 by IHC, while only 6 (54.5%) expressed CA9. On the contrary, all the histologically negative for micrometastases lymph nodes were also negative by IHC analysis for both markers. The comparative diagnostic efficacy of the two markers using qRT-PCR, however, disclosed that the analysis of the same aliquots of the 82 lymph nodes led to 100% specificity for the CK19 biomarker, while, in contrast, CA9 failed to recapitulate a similar pattern. These data suggest that qRT-PCR exhibits a better diagnostic accuracy compared to IHC, while CK19 displays a consistent pattern of detection compared to CA9.
[Show abstract][Hide abstract] ABSTRACT: MicroRNAs (miRNAs) have recently been shown to act as regulatory signals for maintaining stemness and for determining the fate of adult and fetal stem cells, such as human mesenchymal stem cells (hMSCs). hMSCs constitute a population of multipotent stem cells that can be expanded easily in culture and are able to differentiate into many lineages. We have isolated two subpopulations of fetal mesenchymal stem cells (MSCs) from amniotic fluid (AF) known as spindle-shaped (SS) and round-shaped (RS) cells and characterized them on the basis of their phenotypes, pluripotency, proliferation rates, and differentiation potentials. In this study, we analyzed the miRNA profile of MSCs derived from AF, bone marrow (BM), and umbilical cord blood (UCB). We initially identified 67 different miRNAs that were expressed in all three types of MSCs but at different levels, depending on the source. A more detailed analysis revealed that miR-21 was expressed at higher levels in RS-AF-MSCs and BM-MSCs compared with SS-AF-MSCs. We further demonstrated for the first time a direct interaction between miR-21 and the pluripotency marker Sox2. The induction of miR-21 strongly inhibited Sox2 expression in SS-AF-MSCs, resulting in reduced clonogenic and proliferative potential and cell cycle arrest. Strikingly, the opposite effect was observed upon miR-21 inhibition in RS-AF-MSCs and BM-MSCs, which led to an enhanced proliferation rate. Finally, miR-21 induction accelerated osteogenesis and impaired adipogenesis and chondrogenesis in SS-AF-MSCs. Therefore, these findings suggest that miR-21 might specifically function by regulating Sox2 expression in human MSCs and might also act as a key molecule determining MSC proliferation and differentiation.
Full-text · Article · Dec 2013 · STEM CELLS TRANSLATIONAL MEDICINE
[Show abstract][Hide abstract] ABSTRACT: Spot detection is a challenging task of 2D Gel Electrophoresis image analysis. The available software packages and techniques miss some of the protein spots while they detect a high number of spurious spots. This paper introduces a novel approach for the detection of protein spots on 2D gel images which is based on multidirectional texture and spatial intensity information. The proposed approach is compared with two commercial software packages using real 2D-GE images. The outcome demonstrates that the proposed approach outperforms the two software packages; it detects almost all of real protein spots and a low number of spurious spots.
[Show abstract][Hide abstract] ABSTRACT: Background:
A number of mutations in the VSX1 and SOD1 genes have been reported to be associated with keratoconus (KC), however the results from different studies are controversial. In this study, we conducted the genotyping of common polymorphisms [VSX1: D144E, H244R, R166W, G160D; SOD1: intronic 7-base deletion (c.169 + 50delTAAACAG)], in a case-control sample panel of the Greek population.
Materials and methods:
A case-control panel, with 33 KC patients and 78 healthy controls, were surveyed. DNA from each individual was tested for the VSX1: D144E, H244R, R166W, G160D and SOD1: intronic 7-base deletion (c.169 + 50delTAAACAG) polymorphisms by direct sequencing.
We observed no polymorphisms of the VSX1 gene in the case-control panel. Concerning the SOD1 intronic 7-base deletion (c.169 + 50delTAAACAG), our findings suggest that heterozygous carriers are over-represented among KC cases compared to healthy controls (p = 0.002).
We cannot confirm the previously reported association of the polymorphism in the VSX1 gene with KC. Our results suggest a possible causative role of SOD1 in the pathogenesis of KC. Further studies are required to identify other important genetic factors involved in the pathogenesis and progression of KC.
Full-text · Article · Oct 2013 · Ophthalmic Genetics
[Show abstract][Hide abstract] ABSTRACT: The protozoan Trypanosoma brucei causes African Trypanosomiasis or sleeping sickness in humans, which can be lethal if untreated. Most available pharmacological treatments for the disease have severe side-effects. The purpose of this analysis was to detect novel protein-protein interactions (PPIs), vital for the parasite, which could lead to the development of drugs against this disease to block the specific interactions. In this work, the Domain Fusion Analysis (Rosetta Stone method) was used to identify novel PPIs, by comparing T. brucei to 19 organisms covering all major lineages of the tree of life. Overall, 49 possible protein-protein interactions were detected, and classified based on (a) statistical significance (BLAST e-value, domain length etc.), (b) their involvement in crucial metabolic pathways, and (c) their evolutionary history, particularly focusing on whether a protein pair is split in T. brucei and fused in the human host. We also evaluated fusion events including hypothetical proteins, and suggest a possible molecular function or involvement in a certain biological process. This work has produced valuable results which could be further studied through structural biology or other experimental approaches so as to validate the protein-protein interactions proposed here. The evolutionary analysis of the proteins involved showed that, gene fusion or gene fission events can happen in all organisms, while some protein domains are more prone to fusion and fission events and present complex evolutionary patterns.
[Show abstract][Hide abstract] ABSTRACT: β-thalassemias constitute hereditary blood disorders characterized by reduced or absence of β-globin synthesis resulting in mild to severe anemia, depending on the genotype. More than 200 mutations in the β-globin gene are responsible for their specific features leading to a very heterogeneous phenotype. Current therapies for β-thalassemia include blood transfusions, usually along with iron chelation and in selected cases with bone marrow transplantation (BMT) of HLA-matched hematopoietic stem cells (HSCs). However, these approaches are limited by factors, such as iron overload and donor availability, respectively. Since 2000, when globin lentiviral vectors (LVs) were first successfully tested for transfer efficiency of the therapeutic transgene, which led to disease amelioration in murine models, attention was drawn towards the improvement of such vectors for β-thalassemia gene therapy. Constantly improving vector design and efficient HSC manipulation led recently to the first successful clinical trial in France, which further proved that this genetic approach can be curative. Furthermore, improved new efficient vectors and methods to safely monitor integration sites and therapeutic transgene position effects, promise a new era for β-thalassemia gene therapy, with more and safer clinical trials yet to come.
Full-text · Article · Jul 2013 · Current Molecular Medicine
[Show abstract][Hide abstract] ABSTRACT: Gene therapy utilizing lentiviral vectors (LVs) constitutes a real therapeutic alternative for many inherited monogenic diseases. Therefore, the generation of functional vectors using fast, non-laborious and cost-effective strategies is imperative. Among the available concentration methods for VSV-G pseudotyped lentiviruses to achieve high therapeutic titers, ultracentrifugation represents the most common approach. However, the procedure requires special handling and access to special instrumentation, it is time-consuming, and most importantly, it is cost-ineffective due to the high maintenance expenses and consumables of the ultracentrifuge apparatus. Here we describe an improved protocol in which vector stocks are prepared by transient transfection using standard cell culture media and are then concentrated by ultrafiltration, resulting in functional vector titers of up to 6×10(9) transducing units per millilitre (TU/mL) without the involvement of any purification step. Although ultrafiltration per se for concentrating viruses is not a new procedure, our work displays one major novelty; we characterized the nature and the constituents of the viral batches produced by ultrafiltration using peptide mass fingerprint analysis. We also determined the viral functional titer by employing flow cytometry and evaluated the actual viral particle size and concentration in real time by using laser-based nanoparticle tracking analysis based on Brownian motion. Vectors generated by this production method are contained in intact virions and when tested to transduce in vitro either murine total bone marrow or human CD34(+) hematopoietic stem cells, resulted in equal transduction efficiency and reduced toxicity, compared to lentiviral vectors produced using standard ultracentrifugation-based methods. The data from this study can eventually lead to the improvement of protocols and technical modifications for the clinical trials for gene therapy.
[Show abstract][Hide abstract] ABSTRACT: The infliximab (IFX) has dramatically improved the treatment of Crohn's disease (CD). However, the need for predictive factors, indicative of patients' response to IFX, has yet to be met. In the current study, proteomics technologies were employed in order to monitor for differences in protein expression in a cohort of patients following IFX administration, aiming at identifying a panel of candidate protein biomarkers of CD, symptomatic of response to treatment. We enrolled 18 patients, who either had achieved clinical and serological remission (Rm, n=6), or response (Rs, n=6) and/or were PNRs (n=6), to IFX. Serum samples were subjected to two-dimensional Gel Electrophoresis. Following evaluation of densitometrical data, protein spots exhibiting differential expression among the groups, were further characterized by MALDI-TOF-MS. Identified proteins where evaluated by immunoblot analysis while functional network association was carried out to asses significance. Proteins apolipoprotein A-I (APOA1), apolipoprotein E (APOE), complement C4-B (CO4B), plasminogen (PLMN), serotransferrin (TRFE), beta-2-glycoprotein 1 (APOH), and clusterin (CLUS) were found to be up-regulated in the PNR and Rs groups whereas their levels displayed no changes in the Rm group when compared to baseline samples. Additionally, leucine-rich alpha-2-glycoprotein (A2GL), vitamin D-binding protein (VTDB), alpha-1B-glycoprotein (A1BG) and complement C1r subcomponent (C1R) were significantly increased in the serum of the Rm group. Through the incorporation of proteomics technologies, novel serum marker-molecules demonstrating high sensitivity and specificity are introduced, hence offering an innovative approach regarding the evaluation of CD patients' response to IFX therapy.
Full-text · Article · Apr 2013 · Journal of Crohn s and Colitis
[Show abstract][Hide abstract] ABSTRACT: Human mesenchymal stem cells (hMSCs) represent a population of multipotent adherent cells able to differentiate into many lineages. In our previous studies, we isolated and expanded fetal MSCs from second-trimester amniotic fluid (AF) and characterized them based on their phenotype, pluripotency and proteomic profile. In the present study, we investigated the plasticity of these cells based on their differentiation, dedifferentiation and transdifferentiation potential in vitro. To this end, adipocyte-like cells (AL cells) derived from AF-MSCs can regain, under certain culture conditions, a more primitive phenotype through the process of dedifferentiation. Dedifferentiated AL cells derived from AF-MSCs (DAF-MSCs), gradually lost the expression of adipogenic markers and obtained similar morphology and differentiation potential to AF-MSCs, together with regaining the pluripotency marker expression. Moreover, a comparative proteomic analysis of AF-MSCs, AL cells and DAF-MSCs revealed 31 differentially expressed proteins among the three cell populations. Proteins, such as vimentin, galectin-1 and prohibitin that have a significant role in stem cell regulatory mechanisms, were expressed in higher levels in AF-MSCs and DAF-MSCs compared with AL cells. We next investigated whether AL cells could transdifferentiate into hepatocyte-like cells (HL cells) directly or through a dedifferentiation step. AL cells were cultured in hepatogenic medium and 4 days later they obtained a phenotype similar to AF-MSCs, and were termed as transdifferentiated AF-MSCs (TRAF-MSCs). This finding, together with the increase in pluripotency marker expression, indicated the adaption of a more primitive phenotype before transdifferentiation. Additionally, we observed that AF-, DAF- and TRAF-MSCs displayed similar clonogenic potential, secretome and proteome profile. Considering the easy access to this fetal cell source, the plasticity of AF-MSCs and their potential to dedifferentiate and transdifferentiate, AF may provide a valuable tool for cell therapy and tissue engineering applications.
[Show abstract][Hide abstract] ABSTRACT: Human amniotic fluid obtained at amniocentesis, when cultured, generates at least two morphologically distinct mesenchymal stem/stromal cell (MSC) subsets. Of these, the spindle shaped amniotic fluid MSCs (SS-AF-MSCs) contain multipotent cells with enhanced adipogenic, osteogenic and chondrogenic capacity. Here, we demonstrate, for the first time, the capacity of these SS-AF-MSCs to support neovascularization by umbilical cord blood (UCB) endothelial colony forming cell (ECFC) derived cells in both in vitro and in vivo models. Interestingly, although the kinetics of vascular tubule formation in vitro were similar when the supporting SS-AF-MSCs were compared with the best vasculogenic supportive batches of bone marrow MSCs (BMSCs) or human dermal fibroblasts (hDFs), SS-AF-MSCs supported vascular tubule formation in vivo more effectively than BMSCs. In NOD/SCID mice, the human vessels inosculated with murine vessels demonstrating their functionality. Proteome profiler array analyses revealed both common and distinct secretion profiles of angiogenic factors by the SS-AF-MSCs as opposed to the hDFs and BMSCs. Thus, SS-AF-MSCs, which are considered to be less mature developmentally than adult BMSCs, and intermediate between adult and embryonic stem cells in their potentiality, have the additional and very interesting potential of supporting increased neovascularisation, further enhancing their promise as vehicles for tissue repair and regeneration.
[Show abstract][Hide abstract] ABSTRACT: Abstract Dysfunction of the circadian clock genes is involved in the development of obesity and type 2 diabetes (T2D). Since gestational diabetes mellitus (GDM) and T2D share common genetic and phenotypic features, in the present study, we investigated the status of the circadian clock in a cohort of 40 Greek pregnant women with GDM, four with T2D and 20 normal controls. Peripheral blood mRNA transcript levels of 10 clock genes (CLOCK1, BMAL1, PER1, PER2, PER3, PPARΑ, PPARD, PPARG, CRY1 and CRY2) were determined by real-time quantitative PCR. GDM patients expressed significantly lower transcript levels of BMAL1, PER3, PPARD and CRY2 compared to control women (p < 0.05). No significant difference was documented between GDM women maintained either under insulin treatment or diet. A positive correlation was found between the expression of BMAL1 versus CRY2 (r = 0.45, p = 0.003) and BMAL1 versus PPARD (r = 0.43, p = 0.004). Further investigation on the functional relevance of these clock genes, disclosed that expression of PER3 correlated negatively with HbA(1C) levels (r = -0.36, p = 0.022). These data document for the first time that the expression of BMAL1, PER3, PPARD and CRY2 genes is altered in GDM compared to normal pregnant women and support the notion that deranged expression of clock genes may play a pathogenic role in GDM.
No preview · Article · Jan 2013 · Gynecological Endocrinology
[Show abstract][Hide abstract] ABSTRACT: We describe the development of quantum dot (QD) probes for cancer targeting and imaging in living animals. Cadmium selenide (CdSe) QDs with a maximum emission wavelength of 655 nm, shelled with ZnS and a polymer coating presenting carboxylic groups were coated with streptavidin and functionalized with the biotinylated CK19-antibody. In vivo targeting studies of human colorectal cancer growing in mice indicated that the QD probes accumulate at tumors by antibody binding to cancer-specific cell surface biomarkers. Such annroach promises to be highly desirable for molecular targeted research of gastrointestinal cancer.
[Show abstract][Hide abstract] ABSTRACT: Aims:
Recently a relationship between circadian clock function and the risk for type 2 diabetes (T2D) has been shown. BMAL1 is a key component of the mammalian molecular clock. Two SNPs in the BMAL1 gene have been identified to confer T2D susceptibility. In the present study we investigated for the first time the association between the BMAL1 gene and the risk for GDM, in a Greek population.
We studied 185 women with GDM and 161 non-diabetic controls for BMAL1 polymorphisms. For BMAL1 mRNA expression, peripheral leukocytes were harvested from 20 GDM and 20 control women, harboring different genotypes for the tested polymorphisms, using real-time quantitative PCR.
The minor allele (A) of the BMAL1 rs7950226 (G>A) polymorphism was found to be significantly associated with an increased risk of GDM (P=0.025). Analysis of the second BMAL1 rs11022775 (T>C) polymorphism, showed that the C-allele frequency was strongly increased in women with GDM (P=4.455e-06). The CC genotype was also significantly overrepresented in GDM vs. controls (P=0.00001). Additionally, the rs7950226G/rs11022775C and rs7950226A/rs11022775C haplotypes were also found to be associated with increased susceptibility to GDM. Furthermore, the expression levels of BMAL1 mRNA were significantly lower in GDM patients than in controls.
These data suggest that the impairment of the BMAL1 clock gene expression is closely associated with GDM susceptibility.
No preview · Article · Nov 2012 · Diabetes research and clinical practice