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AIM: To investigate the clinicopathologic characteristics and prognostic implications associated with loss of CDX2 expression in colorectal cancers (CRCs). METHODS: We immunohistochemically evaluated CDX2 expression in 713 CRCs and paired our findings to clinicopathologic and molecular characteristics of each individual. Endpoints included cytokeratin 7 and CK20 expression, microsatellite instability, CpG island methylator phenotype, and KRAS and BRAF mutation statuses. Univariate and multivaria

CONTEXT: -Colorectal cancer is a heterogeneous disease entity with 3 molecular carcinogenesis pathways and 2 morphologic multistep pathways. Right-sided colon cancers and left-sided colon and rectal cancers exhibit differences in their incidence rates according to geographic region, age, and sex. A linear tendency toward increasing frequencies of microsatellite instability-high or CpG island methylator phenotype-high cancers in subsites along the bowel from the rectum to the cecum or the ascendi

Several previous studies have demonstrated that the CDX2-negative (CDX2) and/or CK20-negative (CK20) phenotypes of colorectal cancers (CRCs) might be associated with high levels of microsatellite instability (MSI-H). The aim of this study was to investigate the clinicopathologic and molecular features of MSI-H CRCs with different CDX2/CK20 expression statuses. The CDX2 and CK20 expression statuses were immunohistochemically evaluated in 109 MSI-H CRC tissue samples, and the correlations of these

Focal CpG island hypermethylation and diffuse genomic hypomethylation signify the changes in the DNA methylation status in cancer cells. ALU and LINE-1 repetitive DNA elements comprise ~28% of the human genome. PCR-based measurements of these repetitive DNA elements can be used as a surrogate marker of the genomewide methylation content. Our study aimed to identify the timing of ALU and LINE-1 hypomethylations during multistep gastric carcinogenesis and their prognostic implications in gastric c

BACKGROUND: Colorectal cancer (CRC) is a heterogeneous disease in terms of molecular carcinogenic pathways. Based on recent findings regarding the multiple serrated neoplasia pathway, we revised an eight-marker panel for a new CIMP classification system. METHODS: 1370 patients who received surgical resection for CRCs were classified into three CIMP subtypes (CIMP-N: 0-4 methylated markers, CIMP-P1: 5-6 methylated markers and CIMP-P2: 7-8 methylated markers). Our findings were validated in a sepa

Our findings suggest that microsatellite instability plays a more important role than does epigenetic instability in the development of synchronous colorectal cancers, and that information regarding concordant or discordant microsatellite instability status between individual tumors might help to predict clinical outcome of synchronous colorectal cancers.

DNA methylation is one of the key mechanisms of epigenetic modification, and genome-wide hypomethylation and CpG island hypermethylation are characteristics of cancer cells. The CpG island methylator phenotype (CIMP) is a distinctive subtype of colorectal cancers (CRCs) that show concordant hypermethylation of numerous promoter CpG island loci. CIMP-positive CRCs are associated with a proximal location in the colon, microsatellite instability, BRAF mutation and a relatively poor clinical outcome

Annexin A10 expression is associated with poor clinical behavior and can be used a supportive surrogate marker of the serrated neoplasia pathway in invasive CRCs.

PURPOSE: The purpose of this study was to reveal the clinicopathological characteristics and prognostic implications associated with fibroblast growth factor receptor 1 (FGFR1) amplification in colorectal cancers (CRCs). MATERIALS AND METHODS: We measured the copy number of FGFR1 by droplet digital polymerase chain reaction (ddPCR), and analyzed the FGFR1 expression by immunohistochemistry, in 764 surgically resected CRCs (SNUH2007 dataset, 384 CRCs; SNUH Folfox dataset, 380 CRCs). RESULTS: CRCs

AIMS: The precise profile of aberrant expression of thyroid transcription factor-1 (TTF-1) according to antibody clones in colorectal carcinomas (CRCs) has been controversial. Moreover, the detailed clinicopathological and molecular features of CRCs with TTF-1 expression have rarely been investigated. The aim of this study was to evaluate TTF-1 expression status in a large series of CRC cases by using three different antibody clones. METHODS AND RESULTS: Immunohistochemistry for TTF-1 with clone