Aberrant DNA methylation plays a pivotal role in carcinogenesis and its mapping is likely to provide biomarkers for improved diagnostic and risk assessment in prostate cancer (PCa). We quantified and compared absolute methylation levels among 28 candidate genes in 48 PCa and 29 benign prostate hyperplasia (BPH) samples using the pyrosequencing (PSQ) method to identify genes with diagnostic and prognostic potential. RARB, HIN1, BCL2, GSTP1, CCND2, EGFR5, APC, RASSF1A, MDR1, NKX2-5, CDH13, DPYS, PTGS2, EDNRB, MAL, PDLIM4, HLAa, ESR1 and TIG1 were highly methylated in PCa compared to BPH (p < 0.001), while SERPINB5, CDH1, TWIST1, DAPK1, THRB, MCAM, SLIT2, CDKN2a and SFN were not. RARB methylation above 21% completely distinguished PCa from BPH. Separation based on methylation level of SFN, SLIT2 and SERPINB5 distinguished low and high Gleason score cancers, e.g. SFN and SERPINB5 together correctly classified 81% and 77% of high and low Gleason score cancers respectively. Several genes including CDH1 previously reported as methylation markers in PCa were not confirmed in our study. Increasing age was positively associated with gene methylation (p < 0.0001).Accurate quantitative measurement of gene methylation in PCa appears promising and further validation of genes like RARB, HIN1, BCL2, APC and GSTP1 is warranted for diagnostic potential and SFN, SLIT2 and SERPINB5 for prognostic potential.

Morphology evolution and anisotropic phase formation of the maleated polyethylene-layered silicate nanocomposites are investigated by using synchrotron small-angle X-ray scattering (SAXS), transmission electron microscopy (TEM), and polarized optical microscopy (POM). Despite favorable compatibility between polymer and organically modified layered silicates, the final morphology of the nanocomposite evolves via four stages: disordered exfoliation, ordered exfoliation, dual morphologies of intercalation and exfoliation, and intercalation in sequence with the content of silicate. The formation of the ordered exfoliation state is attributed to the steric interaction between anisotropic silicate plates. Particularly, the transition from exfoliation to intercalation provides us with the significant clue that the interaction between layer silicates gets dominant when the distance between them is smaller than a certain value. It is found that the silicate layers need larger layer spacing than 9 nm to avoid the attractive interaction between adjacent silicate layers and to keep the exfoliation state in this nanocomposite system. Additionally, the nanocomposite shows the optical anisotropy above 12 vol % clay due to the ordering of silicate layers. The optical anisotropy becomes stronger with the content of silicate.

Fascin is an actin-binding protein that provides mechanical support and cell motility, and involves cancer cell metastasis. We investigated fascin protein expression in gastric cancer and assessed their relationship with clinicopathologic parameters and survival rates. In addition, we researched galectin-3 protein expression to study fascin action mechanisms. We performed immunohistochemisty with fascin and galectin-3 antibodies in 471 gastric carcinomas, using tissue microarrays. Fascin was positive in 14.9% (70/471) of the samples, and fascin expression was related to worse survival rates (P < 0.001), high clinical stage (P < 0.001), high T stage (P < 0.001), nodal metastasis (P < 0.001), lymphovascular invasion (P= 0.001) and the intestinal type of Lauren classification (P= 0.015). Galectin-3 protein expression was positive in 83.9% (395/471) of the samples and was reversely correlated with fascin protein expression (P= 0.020). Galectin-3 expression was related to low clinical stage (P < 0.001), but not to survival rates in multivariate analysis. In multivariate analysis, fascin expression was related to worse survival rates (HR = 1.56, P= 0.036), and can be an independent poor prognostic factor in gastric cancer.

The purposes of the study are to estimate inbound tourism demand and to analyze the effect of the Korean Wave and Economic indicators on it. For these purposes, we examined the influence of Korean Wave, GDP, CPI and exchange rate on inbound tourism demand for foreign tourists from the USA, China, Japan and Hong Kong to Korea. In order to measure the Korean wave, the export amount of Hallyu related contents exported to each of the four countries is used. GDP means the GDP of each of the four countries. However, the CPI and the exchange rate are relative to Korea. Penal data on tourism demand, Korean Wave, and Economic indicators from 1997 to 2014 are collected for analysis. Through the various tests for panel analysis model selection, the best fit model proved to be a random effect model. As a result, Korean Wave, GDP, and exchange rate have a statistically significant impact on tourism demand. Therefore, it can be seen that the Korean Wave is one of the important factors for attracting foreign tourists to Korea in four countries. Also, the results show that overseas tourism increases when the economic income of the country is high and the exchange rate is favorable. However, CPI does not appear to have a statistically significant impact on tourism demand. This indicates that tourists are not overly concerned about the cost of the travel country when planning a trip.

Digital pathology (DP) using whole slide imaging (WSI) is becoming a fundamental issue in pathology with recent advances and the rapid development of associated technologies. However, the available evidence on its diagnostic uses and practical advice for pathologists on implementing DP remains insufficient, particularly in light of the exponential growth of this industry. To inform DP implementation in Korea, we developed relevant and timely recommendations. We first performed a literature review of DP guidelines, recommendations, and position papers from major countries, as well as a review of relevant studies validating WSI. Based on that information, we prepared a draft. After several revisions, we released this draft to the public and the members of the Korean Society of Pathologists through our homepage and held an open forum for interested parties. Through that process, this final manuscript has been prepared. This recommendation contains an overview describing the background, objectives, scope of application, and basic terminology; guidelines and considerations for the hardware and software used in DP systems and the validation required for DP implementation; conclusions; and references and appendices, including literature on DP from major countries and WSI validation studies.

ObjectiveThis study investigated whether pyrosequencing can be used to determine the methylation status of the MGMT promoter as a clinical biomarker using relatively old archival tissue samples of glioblastoma. We also examined other prognostic factors for survival of glioblastoma patients.MethodsThe available study set included formalin-fixed paraffin-embedded (FFPE) tissue from 104 patients at two institutes from 1997 to 2012, all of which were diagnosed histopathologically as glioblastoma. Clinicopathologic data were collected by review of medical records. For pyrosequencing analysis, the PyroMark Q96 CpG MGMT kit (Qiagen, Hilden, Germany) was used to detect the level of methylation at exon 1 positions 17–39 of the MGMT gene, which contains 5 CpGs.ResultsMethylation of the MGMT promoter was detected in 43 (41.3%) of 104 samples. The average percentage methylation was 14.0±16.8% overall and 39.0±14.7% for methylated cases. There was no significant pattern of linear increase or decrease according to the age of the FFPE block (p=0.687). In multivariate analysis, age, performance status, extent of surgery, method of adjuvant therapy, and methylation status estimated by pyrosequencing were independently associated with overall survival. Additionally, patients with a high level of methylation survived longer than those with low methylation (p=0.016).ConclusionIn this study, the status and extent of methylation of the MGMT promoter analyzed by pyrosequencing were associated with overall survival in glioblastoma patients. Pyrosequencing is a quantitative method that overcomes the problems of MSP and a simple technique for accurate analysis of DNA sequences.

BackgroundIn the majority of melanomas, the RAS/RAF/MEK/ERK signaling pathway is constitutively activated, due to oncogenic mutations in the BRAF and NRAS genes. The BRAF mutation has been mainly described in Caucasian melanomas. However, there is a lack of study evaluating the status, and the clinical significance, of BRAF mutation in the Asian population.ObjectiveThis study was aimed to determine the frequency of BRAF mutation, and to evaluate the correlation of BRAF status with clinicopathologic features and outcomes, in Korean primary acral lentiginous melanoma (ALM) patients.MethodsALM samples (n=36) were analyzed for the BRAF V600E mutation, by dual-priming oligonucleotide (DPO) based real-time polymerase chain reaction. The clinicopathologic features and prognosis of the patients were analyzed with BRAF mutation status.ResultsThe incidence of BRAF V600E mutation was 19.4% (7/36). The BRAF V600E mutations were not associated with clinicopathologic features, except for the age factor. All of the BRAF-mutant patients survived without recurrence or metastasis, and have a better clinical outcome than BRAF wild-type patients.ConclusionIn Korean primary ALM, a low frequency of BRAF mutation was shown; and BRAF mutation presented with a favorable prognosis. These results indicate that other distinctive genetic mechanisms may have more important roles in the development and progression of disease. Further multicenter study with large sample size is firmly needed, to confirm the results of our preliminary study.

Background: The principal objective of this study was to assess clinical outcomes by breast cancer subtype in patients with brain metastases. Methods: Estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2) status was evaluated via immunohistochemical staining. Four survival time intervals were compared according to the subtype (ER+/HER2–, HER2+, triple negative (TN)). Results: 20 (30.3%) of the 66 patients in this study were ER+/HER2–, 20 (30.3%) were HER2+, and 26 (39.4%) were TN. The disease-free survival rates of ER+/HER2–, HER2+, and TN patients were 30.0, 17.0, and 17.9 months, respectively (p = 0.040). The median time intervals from distant metastasis to brain metastasis were 20.6, 19.5, and 9.0 months, respectively (p = 0.012). The times from initial diagnosis to brain metastasis were 52.9, 33.6, and 25.5 months, respectively (p = 0.026). However, the overall survival rates did not differ significantly (p = 0.276). Conclusions: Patients with TN breast cancer were more likely to develop distant metastasis earlier, and also evidenced poor overall survival. Triple receptor status may be employed as a prognostic marker for breast cancer patients with brain metastases.