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Soft tissue sarcomas (STSs) are a rare and fascinating group of diseases that can be subdivided into specific reciprocal translocations in STSs (SRTSs) and nonspecific reciprocal translocations in STSs (NRTSs). PTEN mutations are rare in STSs, suggesting that PTEN expression may be lost by alternative mechanisms such as methylation. In order to reveal whether aberrant PTEN methylation occurs in STSs, MassARRAY Spectrometry was carried to detect methylation patterns of PTEN in STSs. We evaluated methylation levels in 41 CpG sites from −2,515 to −2,186 bp (amplicon A) and −1,786 to −1,416 bp (amplicon B) relative to the translation initiation site in 110 different cases (46 cases of SRTSs, 40 cases of NRTSs, and 24 cases of normal controls). In addition, immunohistochemistry (IHC) was used to detect the loss of PTEN to determine whether PTEN alterations were responsible for decreased PTEN expression. Our data showed that expression of PTEN was diminished in 49 (57%) STSs, whereas the remaining cases (43%) were classified as high expression. Our previous results found that only 2 of 86 cases (2.3%) had a PTEN mutation suggesting that PTEN may be mainly downregulated in STSs by methylation, but not by mutation of PTEN itself. We observed that amplicon A was hypermethylated in STSs with low PTEN expression, whereas normal controls had low methylation levels (P<0.0001), which was not present in amplicon B (P>0.05), nor were there significant differences in the methylation levels in PTEN between SRTS and NRTS cases. The majority of individual CpG units within two amplicons was demonstrated to be hypermethylated. These findings indicate that PTEN hypermethylation is a common event in STSs suggesting that the inactivation of PTEN may be due to hypermethylation in the promoter of PTEN. The aberrant methylation of the CpG sites within PTEN promoter may serve as a potential candidate biomarker for STSs. [ABSTRACT FROM AUTHOR]

Epigenetics may affect the susceptibility for type 2 diabetes mellitus (T2DM). Aberrant DNA methylation patterns are nowadays recognized as a key epigenetic hallmark of T2DM. Previously, our studies have shown that the hypomethylation of human miR-375 promoter may contribute to the pathogenesis of T2DM. However, no comprehensive study defines the miR-375 promoter methylation patterns present in the established pancreatic β cell line. To address this matter, we have analyzed the DNA methylation profile of insulinoma MIN6 cells by MassARRAY spectrometry and employed the DNA demethylating drug 5-aza-2'-deoxycytidine (5-aza-CdR) to treat MIN6 cells to explore the methylation patterns of the mmu-miR-375. The expression of mmu-miR-375 in mRNA level was measured by quantitative RT-PCR (qRT-PCR). Methylation analysis reveals that MIN6 cells display hypermethylation at the mmu-miR-375 promoter. Following the decreased methylation of mmu-miR-375, the relative expression of mmu-miR-375 increased gradually after 5-Aza-CdR treatment. In addition, we find that there was an inverse correlation between DNA methylation levels and transcription level of mmu-miR-375. In summary, this is the first report for analyzing mmu-miR-375 promoter methylation using MALDI-TOF MS technology and our results indicate that promoter hypermethylation of the mmu-miR-375 is a common event in MIN6 cells., Competing Interests: None., (IJCEP Copyright © 2018.)

Epigenetics may affect the susceptibility for type 2 diabetes mellitus (T2DM). Previously, our studies have shown that the hypomethylation of human miR-375 promoter may contribute to the pathogenesis of T2DM. However, the methylation pattern of miR-375 promoter in T2DM is not yet fully understood. In this study, the DNA methylation status of the different region of miR-375 promoter in Chinese Han population with T2DM were explored. 100 Han patients with T2DM and 100 Han healthy controls with normal glucose tolerance (NGT) were collected. Then the transcription level of pre-miR-375 and mature miR-375 were examined using quantitative real-time PCR and the methylation status of 27 CpG sites in the miR-375 promoter was determined by MassARRAY Spectrometry. The relative expression of mature miR-375 was shown as fold difference relative to miR-16 (3.0-fold, P =0.0260) and pre-miR-375 was markedly unregulated (2.6-fold, P =0.0415) in Han T2DM samples. Aberrant methylation was significantly higher within the amplicon of the miR-375 promoter in T2DMs than in NGTs, an average of 10.27% and 7.24% (P=0.0004; Figure 3A), respectively. Further, one CpG unit (CpG&#95;26.27) was significantly hypermethylated in T2DM samples compared with NGT. Together, our results highlights for the first time that aberrant hypermethylation is a common event in Han T2DM, suggesting that the aberrant methylation of the CpG sites within miR-375 promoter may serve as a potential candidate biomarker for T2DM in the Chinese Han population., Competing Interests: None., (IJCEP Copyright © 2017.)

Context: Fetuin-A is an abundant plasma protein known to inhibit insulin signaling and pathologic calcification, has emerged as a promising candidate biomarker for diabetes risk., Objective: The objective of this study was to investigate the relationships between plasma Fetuin-A level with clinical characteristics in patients with new-onset type 2 diabetes mellitus (nT2DM)., Subjects and Methods: Plasma Fetuin-A levels, and clinical characteristics were assessed in 100 patients with nT2DM and 100 normal glucose tolerance (NGT)., Results: nT2DM subjects had significantly higher Fetuin-A levels than NGT subjects (368.5 ± 15.6 vs 152.7 ± 7.1 mg/ml, P < 0.01). In the Pearson's correlation coefficients, Fetuin-A levels and clinical parameters. Fetuin-A was positively correlated with HOMA-insulin resistance index (HOMA-IR), carotid intima media thickness(CIMT), HbA1c, triglyceride (TG), Low-density lipoprotein cholesterol (LDL-C), body mass index (BMI), systolic blood pressure (SBP), fasting plasma glucose (FBG) and 2 h post-glucose load blood glucose (2 h OGTT) (P < 0.05 and P < 0.01), but negatively with fasting plasma insulin (FINS), 2 h plasma insulin after glucose overload (PINS), High-density lipoprotein cholesterol (HDL-C) and HOMA-beta-cell insulin secretion index (HOMA-IS) (P < 0.05 and P < 0.01). However, no significant relationships were observed between plasma Fetuin-A levels and estimated glomerular filtration rate (eGFR), age and gender in nT2DM subjects. In a multiple linear regression analysis, Fetuin-A levels were independently associated with FBG, 2 h OGTT, HOMA-IS, TG, and CIMT (R(2) = 0.6760). CIMT were negatively associated with FINS and HDL-C (r = -0.33, P = 0.008; r = -0.31, P = 0.01, respectively) in the Pearson's analyses. Moreover, they were positively associated with HOMA-IR (r = 0.28, P = 0.03). It showed significant correlations of plasma CIMT with FINS, PINS and HOMA-IR (R(2) = 0.6760)., Conclusions: Our study suggests that the plasma Fetuin-A levels may be associated with macroangiopathies in nT2DM patients. Therefore, detecting early plasma Fetuin-A levels nT2DM provides an opportunity to intervene of carotid artery disease in diabetic patients and giving timely treatment for the prevention of diabetic vascular complications.