Valente Esteves 16_8
نویسندگان
چکیده
Aberrant methylation of seven potential binding sites of the CTCF factor in the differentially methylated region upstream of the H19 gene (H19-DMR) has been suggested as critical for the regulation of IGF2 and H19 imprinted genes. In this study, we analyzed the allele-specific methylation pattern of CTCF binding sites 5 and 6 using methylationsensitive restriction enzyme PCR followed by RFLP analysis in matched tumoral and lymphocyte DNA from head-andneck squamous cell carcinoma (HNSCC) patients, as well as in lymphocyte DNA from control individuals who were cancerfree. The monoallelic methylation pattern was maintained in CTCF binding site 5 in 22 heterozygous out of 91 samples analyzed. Nevertheless, a biallelic methylation pattern was detected in CTCF binding site 6 in a subgroup of HNSCC patients as a somatic acquired feature of tumor cells. An atypical biallelic methylation was also observed in both tumor and lymphocyte DNA from two patients, and at a high frequency in the control group (29 out of 64 informative controls). Additionally, we found that the C/T transition detected by HhaI RFLP suppressed one dinucleotide CpG in critical CTCF binding site 6, of a mutation showing polymorphic frequencies. Although a heterogeneous methylation pattern was observed after DNA sequencing modified by sodium bisulfite, the biallelic methylation pattern was confirmed in 9 out of 10 HNSCCs. These findings are likely to be relevant in the epigenetic regulation of the DMR, especially in pathological conditions in which the imprinting of IGF2 and H19 genes is disrupted.
منابع مشابه
Automatic and Semi-automatic Analysis of the Extension of Myocardial Infarction in an Experimental Murine Model
Rodent models of myocardial infarction (MI) have been extensively used in biomedical research towards the implementation of novel regenerative therapies. Permanent ligation of the left anterior descending (LAD) coronary artery is a commonly used method for inducing MI both in rat and mouse. Post-mortem evaluation of the heart, particularly the MI extension assessment performed on histological s...
متن کاملBrand effects, mobility costs and industry evolution
In this paper I present a model that was built in order to analyse the interdependencies between labour market dynamics and the evolution of industries’ structure. Being inspired by the case of consultancy services, the model integrates many of the features typically found in those industries. In particular, problems of incomplete information, the role of ‘brand effects’, and constraints in the...
متن کاملThe Dawn of New Quantum Dots: Synthesis and Characterization of Ge1-xSnx Nanocrystals for Tunable Bandgaps
متن کامل
A Chemical Analysis of Sediment Pore Water in Oxygen-free Atmosphere: Application to a Contaminated Area
Interstitial water chemistry has been widely studied to identify biological and chemical reactions in the sediment and to assess sediment-water exchange of dissolved chemical compounds (e. g. Sayles 1979; Froelich et al. 1979; Saager et al. 1990; van Raaphorst & Malschaert, 1996). However, sediment pore water sampling is tedious and requires the use of special equipment due to the possible effe...
متن کاملMIQuant – Semi-Automation of Infarct Size Assessment in Models of Cardiac Ischemic Injury
BACKGROUND The cardiac regenerative potential of newly developed therapies is traditionally evaluated in rodent models of surgically induced myocardial ischemia. A generally accepted key parameter for determining the success of the applied therapy is the infarct size. Although regarded as a gold standard method for infarct size estimation in heart ischemia, histological planimetry is time-consu...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2006