DNA methylation: an epigenetic mark of cellular memory.

DNA methylation is a stable epigenetic mark that can be inherited through multiple cell divisions. During development and cell differentiation, DNA methylation is dynamic, but some DNA methylation patterns may be retained as a form of epigenetic memory. DNA methylation profiles can be useful for the lineage classification and quality control of stem cells such as embryonic stem cells, induced pluripotent cells and mesenchymal stem cells. During cancer initiation and progression, genome-wide and gene-specific DNA methylation changes occur as a consequence of mutated or deregulated chromatin regulators. Early aberrant DNA methylation states occurring during transformation appear to be retained during tumor evolution. Similarly, DNA methylation differences among different regions of a tumor reflect the history of cancer cells and their response to the tumor microenvironment. Therefore, DNA methylation can be a useful molecular marker for cancer diagnosis and drug treatment

Dorsal and Ventral Hippocampus Differentiate in Functional Pathways and Differentially Associate with Neurological Disease-Related Genes during Postnatal Development

The dorsal and ventral regions of the hippocampus are important in cognitive and emotional processing, respectively. Various approaches have revealed the differential molecular and structural characteristics, and functional roles of the hippocampus. Recent RNA sequencing (RNA-seq) technology has enriched our understanding of the hippocampus by elucidating more detailed information on gene expression patterns. However, no RNA-seq–based study on gene profiles in the developing hippocampus has been reported. Using RNA-seq–based bioinformatic analysis in conjunction with quantitative real-time polymerase chain reaction analysis and a comparison of in situ hybridization data obtained from the Allen Brain Atlas, we provide a thorough analysis of differentially expressed genes in the dorsal and ventral hippocampus at specific developmental ages representing the postnatally maturing hippocampus. Genes associated with particular functional pathways and marker genes for particular neurological diseases were found to be distinctively segregated within either the dorsal or ventral hippocampus at specific or at all developmental ages examined. We also report novel molecular markers enriched in the dorsal or ventral hippocampus. Taken together, this study provides insights into the molecular mechanisms underlying physiological functions linked to the dorsal or ventral hippocampus. The information provided in the study also contributes to a better understanding of brain functions and serves as a resource for future studies on the pathophysiology of dorsal and ventral hippocampal functions

Unexpected tubal pregnancy at 13 weeks' gestation that was treated with laparoscopic surgery under massive hemoperitoneum

An advanced second trimester tubal pregnancy is rarely encountered because almost all ecopic pregnancy are diagnosed at an early stage. Transvaginal sonography is simple and useful for diagnosing ectopic pregnancy. However, diagnosing the site of ectopic pregnancy and gestational age is sometimes difficult. We experienced a case of an unexpected 13-week tubal pregnancy that was not able to be diagnosed with an accurate pregnancy site and gestational age by transvaginal sonography before surgery. Under massive hemoperitoneum, forceps penetrated the area of pregnancy, which led to further massive bleeding. However, laparoscopic surgery was able to be performed. The findings in our case suggest the importance of examining with transabdominal sonography, especially in an emergency and in advanced tubal pregnancy. In addition, careful manipulation of forceps is required when the ectopic pregnancy mass is large

Cell-Free miR-27a, a Potential Diagnostic and Prognostic Biomarker for Gastric Cancer

MicroRNAs (miRNAs) have been demonstrated to play an important role in carcinogenesis. Previous studies revealed that miRNAs are present in human plasma in a remarkably stable form that is protected from endogenous RNase activity. In this study, we measured the plasma expression levels of three miRNAs (miR-21, miR-27a, and miR-155) to investigate the usefulness of miRNAs for gastric cancer detection. We initially examined plasma miRNA expression levels in a screening cohort consisting of 15 patients with gastric cancer and 15 healthy controls from Korean population, using TaqMan quantitative real-time polymerase chain reaction. We observed that the expression level of miR-27a was significantly higher in patients with gastric cancer than in healthy controls, whereas the miR-21 and miR-155a expression levels were not significantly higher in the patients with gastric cancer. Therefore, we further validated the miR-27a expression level in 73 paired gastric cancer tissues and in a validation plasma cohort from 35 patients with gastric cancer and 35 healthy controls. In both the gastric cancer tissues and the validation plasma cohort, the miR-27a expression levels were significantly higher in patients with gastric cancer. Receiver-operator characteristic (ROC) analysis of the validation cohort, revealed an area under the ROC curve value of 0.70 with 75% sensitivity and 56% specificity in discriminating gastric cancer. Thus, the miR-27a expression level in plasma could be a useful biomarker for the diagnosis and/or prognosis of gastric cancer

The incidence and clinical features of familial pancreatic cancer in Korea

© 2022 Japanese Society of Hepato-Biliary-Pancreatic SurgeryBackground: A history of familial pancreatic cancer (FPC) increases the incidence of pancreatic cancer (PC) among first-degree relatives. We aimed to determine the incidence of FPC and analyze its clinical characteristics. Methods: Between 2010 and 2014, 1159 patients with PC were included in the study. We evaluated the incidence of FPC, clinicopathological features, and survival prognosis between FPC and non-FPC patients. We further analyzed the clinical outcomes of 389 patients with PC who underwent curative-intent surgery. Results: Familial pancreatic cancer incidence was 3.1% (n = 36) among all patients with PC (n = 1159). FPC was diagnosed at an advanced clinical stage compared to non-FPC (P =.041). The tested variables and 5-year survival rate (5YSR) between FPC and non-FPC after propensity score matching had no differences (5YSR: 4.6% vs 2.6%, P =.834). Among PC patients who underwent curative-intent surgery (n = 389), FPC incidence was 1.8% (n = 7). FPC patients were older than non-FPC patients (75.3 ± 4.7 years vs 64.0 ± 9.9 years, P <.001). 5YSR tended to differ between FPC and non-FPC (14.3% vs 22.5%, P =.07) groups. Conclusion: Familial pancreatic cancer is diagnosed at an advanced stage, and FPC that has undergone resection is associated with older age or worse prognosis. A prospective nationwide pedigree registration system was required.N

Experimental model systems for RNA-seq based transcriptome analysis.

<p>(<b>a</b>) Cultured hippocampal neurons expressing EGFP (Lenti-EGFP Ctrl), CCNY-WT-EGFP (Lenti-CCNY-WT-EGFP) or CCNY-shRNA-EGFP (Lenti-CCNY-shRNA-EGFP) via lentiviral expression system. (<b>b</b>,<b>c</b>) Relative levels of mRNA (<b>b</b>) and protein (<b>c</b>) of CCNY from the neurons infected with lentivirus expressing EGFP, CCNY-WT-EGFP or CCNY-shRNA-EGFP. n = 5 from 3 independent experiments. **<i>p</i><0.01 relative to control, ***<i>p</i><0.005 relative to control, student’s <i>t</i> test. Refer to the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0172547#pone.0172547.s009" target="_blank">S9 Fig</a> for the full-length blots of (<b>c</b>). (<b>d</b>) CCNY-WT exists in the spines near the endogenous PDS-95 in cultured hippocampal neurons, supporting the value of the study on systematic analysis for putative neuronal functions of CCNY. Scale bars, 20 and 2 μm for the whole neuronal and enlarged images, respectively.</p