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In MSI-H CRCs, PD-L1+(T) and PD-L1+(I) are linked to a sporadic hypermethylated subtype and an immune cell-rich subtype, respectively. Potential differential therapeutic implications of PD-L1+(T) and PD-L1+(I) in CRCs should be further investigated.

Nonalcoholic fatty liver disease (NAFLD) is associated with visceral obesity. However, the association between visceral adipose tissue (VAT) area and fibrosis in NAFLD patients has not been completely established. This study was aimed to determine the relationship between the computed tomography-measured VAT area and significant fibrosis in NAFLD patients. A total of 324 NAFLD patients and 132 controls were evaluated by liver biopsy. NAFLD was diagnosed based on histological examinations and alc

Colorectal cancers (CRCs) with a high level of microsatellite instability (MSI-H) are clinicopathologically distinct tumors characterized by predominance in females, proximal colonic localization, poor differentiation, mucinous histology, tumor-infiltrating lymphocytes, a Crohn's-like lymphoid reaction and a favorable prognosis. In terms of their molecular features, MSI-H CRCs are heterogeneous tumors associated with various genetic and epigenetic alterations, including DNA mismatch repair defic

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

We aimed to comprehensively investigate the clinicopathologic and molecular implications of altered epithelial cell adhesion molecule (EPCAM) expression in colorectal carcinoma (CRC). EPCAM immunohistochemical expression, EPCAM 3' end deletion, EPCAM promoter methylation, microsatellite instability (MSI), and the CpG island methylator phenotype (CIMP) were analyzed in large cohorts of human CRCs. Among 218 MSI-high CRCs, complete loss (CL) of EPCAM expression was observed in two cases, both of w

Here, we provide an up-to-date review of the histopathology and molecular pathology of serrated colorectal lesions. First, we introduce the updated contents of the 2019 World Health Organization classification for serrated lesions. The sessile serrated lesion (SSL) is a new diagnostic terminology that replaces sessile serrated adenoma and sessile serrated polyp. The diagnostic criteria for SSL were revised to require only one unequivocal distorted serrated crypt, which is sufficient for diagnosi

Periostin is a matricellular protein that interacts with various integrin molecules on the cell surface. Although periostin is expressed in inflamed colonic mucosa, its role in the regulation of intestinal inflammation remains unclear. We investigated the role of periostin in intestinal inflammation using Postn-deficient (Postn-/-) mice. Intestinal epithelial cells (IECs) were transfected by Postn small interfering RNAs. Periostin expression was determined in colon tissue samples from ulcerative

The presence or absence of MLH1 methylation may critically affect the heterogeneity of colorectal carcinoma (CRC) with the CpG island methylator phenotype (CIMP). Here, we investigated the differential characteristics of CIMP-high (CIMP-H) CRCs according to MLH1 methylation status. To further confirm the MLH1-dependent features in CIMP-H CRC, an independent analysis was performed using data from The Cancer Genome Atlas (TCGA). In our CIMP-H CRC samples, MLH1-methylated tumors were characterized

MSI-H CRCs are immunologically heterogeneous, regardless of TMB. The unusual immune-low MSI-H CRCs are characterized by mucinous histology, <i>KRAS</i> mutations, and Wnt/Notch activation, and can be further divided into distinct gene expression subtypes, including CMS4-like CMS1 and CMS3. Our data provide novel insights into precise immunotherapeutic strategies for subtypes of MSI-H tumors.

Our study confirms that the two recently suggested criteria (Ueno criteria and Väyrynen-Mäkinen criteria) for CLR assessment are fairly reproducible methods and can serve as superior prognosticators in CRC.

Brains from six clinically ill guinea pigs from various serial passages infected with brain homogenate from a patient with Creutzfeldt-Jakob disease were studied by light and electron microscopy. There were no appreciable morphologic differences among the animals at different passages. Light microscopy revealed clearing, swelling, and vacuolar changes in neurons and astrocytes. These changes occurred in both perikarya and cell processes. Large isolated vacuoles in the neuropil appeared to develo