Suicide on YouTube:Factors engaging viewers to a selection of suicide-themed videos.

Visual social media platforms can function as both facilitators and intervenors of concerning behaviors. This study focused on one of the health concerns worldwide, a leading cause of death related to mental health-suicide-in the context of a dominant visual social media platform, YouTube. This study employed content analysis method to identify the factors predicting viewer responses to suicide-themed content from the perspectives of who's, what's, and how's of suicide-themed videos. The results of the hierarchical multiple regression showed that the characteristics of content provider and content expression were more significant predictors of viewer engagement than were the characteristics of the message. These findings have implications for not only platform service providers but also diverse groups of individuals who participate in online discussions on suicide. YouTube has the potential to function as a locus for open discussion, education, collective coping, and even the diagnosis of suicidal ideation.

A functional regulatory variant of MYH3 influences muscle fiber-type composition and intramuscular fat content in pigs.

Muscle development and lipid accumulation in muscle critically affect meat quality of livestock. However, the genetic factors underlying myofiber-type specification and intramuscular fat (IMF) accumulation remain to be elucidated. Using two independent intercrosses between Western commercial breeds and Korean native pigs (KNPs) and a joint linkage-linkage disequilibrium analysis, we identified a 488.1-kb region on porcine chromosome 12 that affects both reddish meat color (a*) and IMF. In this critical region, only the MYH3 gene, encoding myosin heavy chain 3, was found to be preferentially overexpressed in the skeletal muscle of KNPs. Subsequently, MYH3-transgenic mice demonstrated that this gene controls both myofiber-type specification and adipogenesis in skeletal muscle. We discovered a structural variant in the promotor/regulatory region of MYH3 for which Q allele carriers exhibited significantly higher values of a* and IMF than q allele carriers. Furthermore, chromatin immunoprecipitation and cotransfection assays showed that the structural variant in the 5'-flanking region of MYH3 abrogated the binding of the myogenic regulatory factors (MYF5, MYOD, MYOG, and MRF4). The allele distribution of MYH3 among pig populations worldwide indicated that the MYH3 Q allele is of Asian origin and likely predates domestication. In conclusion, we identified a functional regulatory sequence variant in porcine MYH3 that provides novel insights into the genetic basis of the regulation of myofiber type ratios and associated changes in IMF in pigs. The MYH3 variant can play an important role in improving pork quality in current breeding programs.

Mobile Health Management Platform-Based Pulmonary Rehabilitation for Patients With Non-Small Cell Lung Cancer: Prospective Clinical Trial.

BACKGROUND: Lung cancer patients experience various symptoms during treatment. Although pulmonary rehabilitation is an effective way to improve these symptoms, a medical environment of limited availability makes it difficult to provide seamless and adequate rehabilitation for lung cancer patients. OBJECTIVE: This study aimed to investigate the effects of a personalized pulmonary rehabilitation program using real-time mobile patient health data for patients with non-small cell lung cancer. METHODS: We conducted a prospective clinical trial in 64 patients with non-small cell lung cancer aged between 20 and 80 years at a large tertiary hospital in Seoul, South Korea. A 12-week personalized pulmonary rehabilitation program, called efil breath, was administered to determine the effectiveness of the newly developed rehabilitation app. Participants were randomly allocated to the fixed exercise or fixed-interactive exercise group (which received the personalized program). We measured changes in 6-minute walk distance (6MWD) and dyspnea (modified Medical Research Council [mMRC] score) at 6 weeks; and quality of life and service satisfaction at 12 weeks. We used the paired t test to analyze the variables. RESULTS: Patients used the newly developed mobile health pulmonary rehabilitation app and a real-time patient monitoring website. In all participants, significant changes were observed in 6MWD at 12 weeks from a mean of 433.43m (SD 65.60) to 471.25m (SD 75.69; P=.001), and mMRC from a mean score of 0.94 (0.66) to 0.61 (SD 0.82; P=.02). The intervention significantly improved their quality of life (EuroQol-visual analog scale [EQ-VAS]) compared with baseline (mean score 76.05, SD 12.37 vs 82.09, SD 13.67, respectively; P=.002). CONCLUSIONS: A personalized mobile health-based pulmonary rehabilitation app for recording and monitoring real-time health data of patients with non-small cell lung cancer can supplement traditional health care center-based rehabilitation programs. This technology can encourage improvement of physical activity, dyspnea, and quality of life.

An mHealth Management Platform for Patients with Chronic Obstructive Pulmonary Disease (efil breath): Randomized Controlled Trial.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is one of the major morbidities in public health, and the use of mHealth technology for rehabilitation of patients with COPD can help increase physical activity and ameliorate respiratory symptoms. OBJECTIVE: This study aimed to develop a comprehensive rehabilitation management platform to improve physical activity and quality of life in patients with COPD. METHODS: The study comprised the following 2 stages: (1) a pilot stage in which a prototype app was developed; and (2) a fully-fledged platform development stage in which 2 apps and 1 COPD patient monitoring website were developed. We conducted a randomized clinical trial to investigate the efficacy of the apps developed in the second stage of the study. In addition, two 12-week exercise regimens (fixed and fixed-interactive) were tested for the trial. The clinical parameters of the respiratory function and patient global assessment (PGA) of the app were obtained and analyzed. Notably, Android was the chosen operating system for apps. RESULTS: We developed 2 COPD rehabilitation apps and 1 patient monitoring website. For the clinical trial, 85 patients were randomized into the following 3 groups: 57 were allocated to the 2 intervention groups and 28 to the control group. After 6 weeks, the COPD assessment test scores were significantly reduced in the fixed group (P=.01), and signs of improvement were witnessed in the fixed-interactive group. In addition, the PGA score was moderate or high in all aspects of the user experience of the apps in both intervention groups. CONCLUSIONS: A well-designed mobile rehabilitation app for monitoring and managing patients with COPD can supplement or replace traditional center-based rehabilitation programs and achieve improved patient health outcomes. TRIAL REGISTRATION: ClinicalTrials.gov NCT03432117; https://clinicaltrials.gov/ct2/show/NCT03432117 (Archived by WebCite at http://www.webcitation.org/71Yp0P64a).

Export of membrane proteins from the Golgi complex to the primary cilium requires the kinesin motor, KIFC1.

Microtubule-based motors contribute to the efficiency and selectivity of Golgi exit and post-Golgi transport of membrane proteins that are targeted to distinct compartments. Cytoplasmic dynein moves post-Golgi vesicles that carry rhodopsin toward the base of the connecting cilium in photoreceptor cells; however, the identity of the motors that are involved in the vesicular trafficking of ciliary membrane proteins in nonphotoreceptor cells remains unclear. Here, we demonstrate that the minus end-directed kinesin KIFC1 (kinesin family member C1) is required for both ciliary membrane protein transport and serum starvation-induced ciliogenesis in retinal pigmented epithelial 1 cells. Although KIFC1 is known as a mitotic motor that is sequestered in the nucleus during interphase, KIFC1 immunoreactivity appeared in the Golgi region after serum starvation. Knockdown of KIFC1 inhibited the export of ciliary receptors from the Golgi complex. KIFC1 overexpression affected the Golgi localization of GMAP210 (Golgi microtubule-associated protein 210) and IFT20 (intraflagellar transport 20), which are involved in membrane protein transport to cilia. Moreover, KIFC1 physically interacted with ASAP1 (ADP-ribosylation factor GTPase-activating protein with SH3 domain, ankyrin repeat and PH domain 1), which regulates the budding of rhodopsin transport carriers from the Golgi complex, and KIFC1 depletion caused Golgi accumulation of ASAP1. A decrease in the centrosomal levels of IFT20 and TTBK2 (τ-tubulin kinase 2) was associated with ciliogenesis defects in KIFC1-depleted cells. Our results suggest that KIFC1 plays roles in the Golgi exit of ciliary receptors and in the recruitment of ciliogenesis regulators.-Lee, S.-H., Joo, K., Jung, E. J., Hong, H., Seo, J., Kim, J. Export of membrane proteins from the Golgi complex to the primary cilium requires the kinesin motor, KIFC1.

Energy Expenditures for Activities of Daily Living in Korean Young Adults: A Preliminary Study.

OBJECTIVE: To investigate the energy expenditure (EE) of Korean young adults based on activities refined to a deskbound lifestyle. METHODS: Sixty-four healthy office workers aged between 25 and 46 years participated in this study. EE was expressed as metabolic equivalent of task (MET). Participants were evaluated in terms of their EE during physical activities of sleeping (n=22), typing (n=37), folding laundry (n=34), dishwashing (n=32), studying (n=18), mopping (n=35), walking (n=33), stair climbing (n=23), and running (n=29). Volume of oxygen consumption was measured by indirect calorimetry K4b(2) (COSMED). The results were compared to the established Compendium MET. RESULTS: The MET of activities were: sleeping, 1.24±0.43; typing, 1.35±0.25; folding laundry, 1.58±0.51; dishwashing, 2.20±0.51; studying, 2.11±0.90; mopping, 2.72±0.69; walking at 4 km/hr, 3.48±0.65; stair climbing of five stories, 6.18±1.08; and running at 8 km/hr, 7.57±0.57. The values of typing and mopping were similar to those in the Compendium, whereas those of sleeping, folding laundry, dishwashing, studying, walking, stair climbing and running were different. CONCLUSION: To our knowledge, this estimation of EE in MET during activities of daily living is the first data of young adults in Korea. These data could be used as a reference to modify the guidelines of physical activities for the age group examined in this study.

Curcumin induces ER stress-mediated apoptosis through selective generation of reactive oxygen species in cervical cancer cells.

Prolonged accumulation of misfolded or unfolded proteins caused by cellular stress, including oxidative stress, induces endoplasmic reticulum stress, which then activates an unfolded protein response (UPR). ER stress is usually maintained at higher levels in cancer cells as compared to normal cells due to altered metabolism in cancer. Here, we investigated whether curcumin is ER stress-mediated apoptosis in cervical cancer cells, and ROS increased by curcumin are involved in the process as an upstream contributor. Curcumin inhibited proliferation of cervical cancer cells (C33A, CaSki, HeLa, and ME180) and induced apoptotic cell death. Curcumin activated ER-resident UPR sensors, such as PERK, IRE-1α, and ATF6, and their downstream-signaling proteins in cervical cancer cells, but not in normal epithelial cells and peripheral blood mononuclear cells (PBMCs). CHOP, a key factor involved in ER stress-mediated apoptosis, was also activated by curcumin. CHOP decreased the ratio of anti-apoptotic protein Bcl-2 to pro-apoptotic protein Bax expression, and subsequently increased the apoptotic population of cervical cancer cells. Furthermore, curcumin elevated levels of intracellular reactive oxygen species (ROS) in cervical cancer cells, but not in normal epithelial cells. Scavenging ROS resulted in inhibition of ER stress and partially restored cell viability in curcumin-treated cancer cells. Collectively, these observations show that curcumin promotes ER stress-mediated apoptosis in cervical cancer cells through increase of cell type-specific ROS generation. Therefore, modulation of these differential responses to curcumin between normal and cervical cancer cells could be an effective therapeutic strategy without adverse effects on normal cells.

Genome-wide QTL analysis of meat quality-related traits in a large F2 intercross between Landrace and Korean native pigs.

BACKGROUND: We conducted a genome-wide linkage analysis to identify quantitative trait loci (QTL) that influence meat quality-related traits in a large F2 intercross between Landrace and Korean native pigs. Thirteen meat quality-related traits of the m. longissimus lumborum et thoracis were measured in more than 830 F2 progeny. All these animals were genotyped with 173 microsatellite markers located throughout the pig genome, and the GridQTL program based on the least squares regression model was used to perform the QTL analysis. RESULTS: We identified 23 genome-wide significant QTL in eight chromosome regions (SSC1, 2, 6, 7, 9, 12, 13, and 16) (SSC for Sus Scrofa) and detected 51 suggestive QTL in the 17 chromosome regions. QTL that affect 10 meat quality traits were detected on SSC12 and were highly significant at the genome-wide level. In particular, the QTL with the largest effect affected crude fat percentage and explained 22.5% of the phenotypic variance (F-ratio = 278.0 under the additive model, nominal P = 5.5 × 10(-55)). Interestingly, the QTL on SSC12 that influenced meat quality traits showed an obvious trend for co-localization. CONCLUSIONS: Our results confirm several previously reported QTL. In addition, we identified novel QTL for meat quality traits, which together with the associated positional candidate genes improve the knowledge on the genetic structure that underlies genetic variation for meat quality traits in pigs.

Genome-wide association analysis to identify SNP markers affecting teat numbers in an F2 intercross population between Landrace and Korean native pigs.

Most reproductive traits have low heritability and are greatly affected by environmental factors. Teat number and litter size are traits related to the reproduction ability of pigs. To identify quantitative trait loci (QTLs) for teat number traits, a genome-wide association study (GWAS) was conducted using an F2 intercross between Landrace and Korean native pigs. Genotype analysis was performed using the porcine SNP 60 K beadchip. The GWAS was performed using a mixed-effects model and linear regression approach. When a genome-wide threshold was determined using the Bonferroni method (P = 1.61 × 10(-6)), 38 single nucleotide polymorphism (SNP) markers in pig chromosome 7 (SSC7) were significantly associated with three teat number traits (total teat number, left teat number, and right teat number). Among these, SNPs in 5 genes (HDDC3, LOC100156276, LOC100155863, ANPEP, SCAMP2) were selected for further study based primarily on their statistical significance. A significant association was detected in SCAMP2 g.25280 G>A for total teat number (P = 2.0 × 10(-12)), HDDC3 g.1319 G>A SNP for left teat number (P = 2.3 × 10(-7)), and SCAMP2 g.14198 G>A for right teat number (P = 4.7 × 10(-12)). These results provide valuable information about the selective breeding for desirable teat numbers in pigs.

c-MYC amplification in mucinous gastric carcinoma: a possible genetic alteration leading to deeply invasive tumors.

BACKGROUND: Patients with mucinous gastric carcinoma (MGC) usually have a poor prognosis, largely due to the advanced stage of disease. In this study, we evaluated the effects of c-MYC amplification on tumor stage and disease-specific survival of 128 patients with MGC and compared the results with those of 302 patients with non-mucinous gastric carcinoma (non-MGC). PATIENTS AND METHODS: Two-color fluorescence in situ hybridization (FISH) for c-MYC was performed on 430 GC samples. Real-time quantitative polymerase chain reaction (q-PCR) analysis for c-MYC was also performed after tumor microdissection. RESULTS: c-MYC amplification was found in 10.2% of MGCs and 6.0% of non-MGCs. c-MYC amplification was more frequently found in MGCs of higher tumor stage than in MGCs of lower stage (p=0.038). c-MYC amplification in MGC was correlated with greater invasion depth (p=0.007). The mean survival time of patients with c-MYC amplification was shorter than that of patients without c-MYC amplification in MGC. Real-time q-PCR results showed that the calculated c-MYC/GAPDH ratios were higher in c-MYC-amplified MGC than in c-MYC-non-amplified MGC. CONCLUSION: This study showed that c-MYC amplification in MGC is highly correlated with advanced stage and deeply invasive MGC. This suggests that c-MYC amplification in MGC could be a possible genetic alteration contributing to the frequent presentation of advanced-stage MGC.

A missense mutation (c.1963A

Serum Ca(++) levels play important roles in the humoral immunity. The aim of this study was to detect quantitative trait loci and the associated positional candidate genes affecting baseline serum Ca(++) concentrations. A genome-wide association study was conducted in an F(2) intercross population between Landrace and Korean native pigs using the porcine single nucleotide polymorphism (SNP) 60 K beadchip and the PLINK program based on linear regression. Data used in the study included 410 F(2) pigs. All experimental animals were genotyped with 36,613 SNP markers located throughout the pig autosomes. We identified a strong association between a SNP marker on chromosome 7 and serum Ca(++) levels (DIAS0002191, genomic control-corrected P = 7.7 × 10(-5)). The position of DIAS0002191 was closely located to SLA class III region containing the C2 gene encoding the complementary component 2 protein, a protein which is important in the humoral immune responses. De novo sequencing of the porcine C2 gene revealed a missense mutation [c.1963A

Prognostic significance of glutathione peroxidase 1 (GPX1) down-regulation and correlation with aberrant promoter methylation in human gastric cancer.

BACKGROUND: This study aimed at examining the association of gene silencing and promoter methylation of glutathione peroxidase 1 (GPX1) and glutathione peroxidase 3 (GPX3) in gastric cancer cells and determined the clinical significance of GPX1 and GPX3 expression loss in gastric cancer tissue. MATERIALS AND METHODS: Analysis of mRNA expression was carried out by reverse transcription-polymerase chain reaction (RT-PCR). Methylation of the GPX1 promoter region was analyzed by bisulfite sequencing, and that of the GPX3 promoter region was analyzed by methylation-specific PCR (MSP). Tissue microarray-based immunohistochemistry of GPX1 and GPX3 in 1,163 resected gastric cancer specimens was performed to assess the associations with clinicopathological parameters. RESULTS: Reduced GPX1 and GPX3 mRNA expression was associated with promoter methylation in gastric cancer cell lines. A correlation between DNA promoter methylation and loss of GPX1 expression was noted in 16 gastric cancer tissue samples (p=0.005). Loss of GPX1 and GPX3 proteins was found in 24.4% and 30.8% of gastric cancer tissues. Loss of GPX1 expression was significantly associated with advanced gastric cancer (p=0.039) and lymphatic invasion (p=0.010); loss of GPX3 expression was associated with advanced gastric cancer (p<0.001) and lymph node metastasis (p<0.001). Kaplan-Meier analysis showed that low expression of GPX1 was associated with poor cancer-specific survival (p=0.010). CONCLUSION: Data from this study implicate aberrant hypermethylation of promoter regions of GPX1 and GPX3 as a mechanism for down-regulation of GPX1 and GPX3 mRNA expression in gastric cancer cells. Loss of GPX1 expression was associated with aggressiveness and poor survival in patients with gastric cancer.

QTL analysis of clinical-chemical traits in an F2 intercross between Landrace and Korean native pigs.

Clinical-chemical traits are essential when examining the health status of individuals. The aim of this study was to identify quantitative trait loci (QTL) and the associated positional candidate genes affecting clinical-chemical traits in a reciprocal F(2) intercross between Landrace and Korean native pigs. Following an overnight fast, 25 serum phenotypes related to clinical-chemical traits (e.g., hepatic function parameters, renal function parameters, electrolyte, lipids) were measured in >970 F(2) progeny. All experimental samples were subjected to genotyping analysis using 165 microsatellite markers located across the genome. We identified eleven genome-wide significant QTL in six chromosomal regions (SSC 2, 7, 8, 13, 14, and 15) and 59 suggestive QTL in 17 chromosomal regions (SSC 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 17, and 18). We also observed significant effects of reciprocal crosses on some of the traits, which would seem to result from maternal effect, QTL on sex chromosomes, imprinted genes, or genetic difference in mitochondrial DNA. The role of genomic imprinting in clinical-chemical traits also was investigated. Genome-wide analysis revealed a significant evidence for an imprinted QTL in SSC4 affecting serum amylase levels. Additionally, a series of bivariate linkage analysis provided strong evidence that QTL in SSC 2, 13, 15, and 18 have a pleiotropic effect on clinical-chemical traits. In conclusion, our study detected both novel and previously reported QTL influencing clinical-chemical traits in pigs. The identified QTL together with the positional candidate genes identified here could play an important role in elucidating the genetic structure of clinical-chemical phenotype variation in humans and swine.

Fibroblast growth factor receptor 2 gene amplification status and its clinicopathologic significance in gastric carcinoma.

Fibroblast growth factor receptor 2 is a member of receptor tyrosine kinase family, and fibroblast growth factor receptor 2 gene amplification or missense mutation has been observed in various human cancers, including gastric carcinoma. Recent studies have shown that anti-fibroblast growth factor receptor 2 agents inhibit tumor progression in various human cancers, such as endometrial carcinoma and gastric carcinoma, which remains one of the most frequent causes of cancer-related death worldwide. We considered that knowledge of the status of fibroblast growth factor receptor 2 gene amplification in gastric carcinoma might aid in targeted cancer therapy. In this study, fibroblast growth factor receptor 2 amplification status was evaluated by fluorescence in situ hybridization in 313 surgically resected gastric carcinoma tissues, and the results were validated by quantitative real-time polymerase chain reaction. In addition, potential associations between clinicopathologic parameters and the presence of fibroblast growth factor receptor 2 amplification were investigated, and survival analysis was performed. Of the 313 cases, 14 (4.5%) showed fibroblast growth factor receptor 2 amplification by fluorescence in situ hybridization. Fibroblast growth factor receptor 2 amplification was found to be associated with a higher pT stage (P = .023), higher pN stage (P = .038), and distant metastasis (P = .009) and to be significantly associated with lower cancer-specific survival by univariate analysis (P = .012). Gastric carcinoma with fibroblast growth factor receptor 2 amplification was found to be associated with advanced disease and a poor prognosis. We believe that the determination of fibroblast growth factor receptor 2 amplification status could allow the identification of a subset of cancers sensitive to targeted fibroblast growth factor receptor 2 inhibitor-based therapy.

Identification of P2Y12 single-nucleotide polymorphisms and their influences on the variation in ADP-induced platelet aggregation.

INTRODUCTION: Although P2Y12 has a significant role in normal hemostasis and thrombosis, no genetic study has been described about the association between P2Y12 variants and the extent of ADP-induced platelet activation in the Korean population. MATERIALS AND METHODS: The expression levels of two reference sequences of P2Y12 mRNA transcripts (variants 1 and 2) were examined in the whole blood before direct DNA sequencing. The subjects were screened for single-nucleotide polymorphisms (SNPs) in P2Y12 by direct DNA sequencing (n=50). Frequencies of P2Y12 single nucleotide polymorphisms (SNPs), linkage disequilibrium blocks, haplotype structures, and haplotype-tagging SNPs were determined. The effects of genetic variation in the P2Y12 gene on the extent of ADP-induced platelet aggregation were studied in healthy Korean men (n=40). RESULTS: Variant 2 (NM 176876.1) was the predominantly expressed form in all subjects, but variant 1 was also weakly expressed in all cases (n=10). A total of 20 SNPs were identified: 2 in exons, 5 in introns, and 8 and 5 in the 5'-untranslated regions of the known P2Y12 RNA variants 1 and 2, respectively. Genetic analysis of the P2Y12 SNPs and haplotypes revealed a statistically significant association between P2Y12 haplotype, denoted H3, and an increase in the ADP-induced platelet aggregation response relative to that for the reference haplotype H1 (P=0.01). CONCLUSIONS: Application of these findings to the development of a multivariate model might be useful in explaining the variable outcome of antiplatelet drug therapy in Asian populations.

Expression of BamHI-A Rightward Transcripts in Epstein-Barr Virus-Associated Gastric Cancers.

PURPOSE: About 10% of all gastric cancers (GCs) are Epstein-Barr virus (EBV)-associated. However, the oncogene of EBV in gastric carcinogenesis has not yet been established. In the present study, we investigated the virus-derived transcripts in the EBV-infected GC cell line to explore the viral oncogene of EBV-positive GCs. MATERIALS AND METHODS: We used the SNU719 cell line, a naturally derived EBV-infected GC cell line. The individual expressed sequence tags from the cDNA libraries of SNU719 were searched against the mRNA subset extracted from the GenBank data base. Sequence reaction was carried out for the EBV-associated clones. Reverse transcription-polymerase chain reaction was performed after cells were partitioned into nuclear and cytoplasmic fractions. RESULTS: Using bioinformatic tools, we selected 13 EBV-associated clones from cDNA libraries of SNU719. By sequencing analysis, we revealed that they were all associated with RPMS1, one of the BamHI-A rightward transcripts (BART) of EBV. Some BART cDNAs such as RPMS1 and A73 are known to be translated into protein in vitro, and have been shown to have some biochemical functions relevant to tumorigenesis. But, presently, the BART transcripts were expressed only in the nucleus and not in the cytoplasm, arguing against their role as messenger RNAs. Some other BART transcripts expressed in GCs (BARF0, CST, vIL, BARF1, BLLF1, and BcLF1) were also extensively detected in the nucleus. CONCLUSION: BART transcripts are the predominant viral transcripts expressed in EBV-associated GCs, and they are located only in the nucleus. Therefore, it seems less likely that BART transcripts produce functional proteins to play a role in carcinogenesis of EBV-associated GCs.

P-cadherin expression in gastric carcinoma: its regulation mechanism and prognostic significance.

P-cadherin is a member of the cadherin family and is expressed in several solid tumors. This molecule was recently highlighted with the development of a new targeted compound being studied in a clinical trial on solid tumors. In the present study, we examined the protein and messenger RNA (mRNA) expression status of P-cadherin and its promoter methylation in gastric carcinoma cell lines and tissues. Of the 10 cell lines, 4 were found to express P-cadherin protein and mRNA, and the P-cadherin gene was found to be hypomethylated in its promoter region in these cell lines. Nonneoplastic gastric mucosal tissues from gastric carcinoma patients were negative for P-cadherin protein evaluated by immunohistochemistry and Western blotting and had a methylated P-cadherin promoter region. In carcinoma tissues, 70.8% (749/1058) of cases showed P-cadherin protein expression, and P-cadherin positive cases had a well or moderately differentiated histology according to the World Health Organization classification, intestinal-type histology by Lauren classification, and an earlier pT class. Furthermore, patients with P-cadherin expressing tumors had a favorable prognosis by univariate and multivariate survival analyses. In addition, P-cadherin protein expression was found to be significantly correlated with promoter hypomethylation. In summary, P-cadherin is silenced in nonneoplastic gastric mucosa, and P-cadherin expressing tumors constitute a subset of gastric carcinoma with intestinal-type histology and a favorable prognosis. In addition, our findings suggest that P-cadherin promoter methylation underlies the regulation of its expression. These findings may aid patient selection and the interpretation of P-cadherin targeted therapy and clinical trial results.

Reduced expression and homozygous deletion of annexin A10 in gastric carcinoma.

Annexins (ANXs) are a family of calcium and phospholipid binding proteins that have been implicated in diverse important biological and physiological process. ANX A10 (ANXA10) is a member of this family, though little is known about its functions. In the present study, array based comparative genomic hybridization (CGH) was used to screen DNA copy number change in gastric cancer cell lines and the results obtained were compared with oligonucleotide microarray data. DNA loss of the ANXA10 locus in chromosome 4q33 was found in several gastric cancer cell lines by array based CGH and these cell lines showed decreased ANXA10 expression by oligonucleotide microarray analysis. Functional analysis using siRNA and full-length cDNA transfection in gastric cancer cell lines demonstrated that ANXA10 regulates gastric cancer cell proliferation. Of the 585 primary gastric carcinoma tissues examined, ANXA10 expression at the protein level was found to be reduced in 289 (49.4%) cases. Quantitative real-time PCR analysis validated loss of DNA at the ANXA10 locus in gastric carcinomas with reduced ANXA10 expression. By univariate survival analysis, lack of ANXA10 expression was associated with poor survival (p = 0.016). These results suggest that ANXA10 inactivation by chromosomal deletion may play a role during gastric cancer progression.

Comparative analysis of DNA methylation between primary and metastatic gastric carcinoma.

Metastasis is a multi-step process involving many biomolecular changes and DNA methylation is one such molecular change. Although differences in DNA methylation have been reported in matched primary and metastatic mammary carcinoma, no such differences have been reported in gastric carcinoma. Accordingly, to investigate whether DNA methylation profiles in metastatic gastric carcinoma differ from those of their primary counterparts, we investigated the DNA methylation of eleven genes, ADAM23, CDH1, FHIT, FLNC, GSTP1, ITGA4, LOX, RUNX3, THBS1, TIMP3, and UCHL1 in 74 matched human primary gastric carcinomas, lymph node metastases, non-neoplastic gastric mucosal, and uninvolved lymph node tissues by utilizing methylation-specific PCR. Seven of these genes (ADAM23, FLNC, ITGA4, LOX, RUNX3, TIMP3, and UCHL1) showed cancer-specific methylation, and three (CDH1, FHIT, and THBS1) showed cancer-unrelated methylation. GSTP1 was rarely methylated in any tissue type. Of the seven genes that showed cancer-specific methylation, FLNC was more frequently methylated in metastatic gastric carcinomas than in their primary counterparts (p=0.004). In addition, the average number of methylated genes in metastatic tumors was greater than that in primary tumors (p=0.004). The high-methylation group (cases with three or more genes methylated in primary tumors) was found to contain more women (p=0.031) and diffuse type tumors by Lauren classification (p=0.022). DNA methylation profiles were not found to affect prognosis. We suggest that promoter methylation of FLNC may be involved in the lymph node metastasis of gastric carcinoma and that the DNA methylation statuses of metastatic tumors should be considered in node-positive gastric carcinoma.

Cloning and characterization of cat POU5F1 and NANOG for identification of embryonic stem-like cells.

POU5F1 and NANOG play important roles in the maintenance of embryonic stem cell pluripotency. Recently, we isolated cat embryonic stem (ES)-like cells from cat blastocysts generated in vivo. In an effort to identify genetic markers for the characterization of cat ES-like cells, we have determined the coding sequences (CDSs) of cat POU5F1 (cPOU5F1) and NANOG (cNANOG). The sequence identities of cPOU5F1 with orthologous genes of the human and mouse were 92 and 82%, respectively, at the nucleotide level and 94 and 83%, respectively, at the amino acid level. We identified POU-specific and POU homeodomain sequences in the CDS of cPOU5F1. The sequence identities of cNANOG with its human and mouse orthologs were 69 and 68%, respectively, at the nucleotide level and 69 and 58%, respectively, at the amino acid level. We identified a homeodomain, SMAD4 domain and tryptophan repeat domain (W/QXXXX) in the CDS of cNANOG. We examined the expression of cPOU5F1 and cNANOG mRNA in ES-like cells and fibroblast feeder cells by RT-PCR. Transcripts of cPOU5F1 and cNANOG were detected at a high level in ES-like cells. However, these two genes were undetectable in cat fibroblast feeder cells and 6 adult tissues. We also examined ES-like cells by immunocytochemistry and demonstrated that cPOU5F1 and cNANOG are present at high levels in cat ES-like cells and are undetectable in cat fibroblast feeder cells. These results confirmed that cat ES-like cells can be successfully isolated from in vivo-produced blastocysts and that the expression of cPOU5F1 and cNANOG can be used as a biomarker for characterization of cat ES-like cells.