Background & Aims: Inactivation of the CDKN2/p16(INK4A) tumor-suppressor gene is one of the most frequent genetic alterations in human malignancies. In esophageal adenocarcinomas, mutations of the p16 gene or homozygous deletions of the gene locus 9p21 are rare. This study investigated whether p16 promoter hypermethylation is an alternative mechanism for p16 gene inactivation during neoplastic progression in Barrett's esophagus.
Methods: A methylation-specific polymerase chain reaction protocol was applied. A total of 95 specimens from 14 patients with Barrett's esophagus were analyzed longitudinally. The p16 promoter status was compared with histomorphological findings.
Results: p16 promoter hypermethylation was detected in 9 of the 10 patients who had displayed dysplasia at some time during surveillance, whereas none of the patients who had not displayed dysplasia during surveillance had p16 promoter hypermethylation. p16 promoter hypermethylation was detected in 3% (2 of 67) of the samples without dysplasia, 60% (3 of 5) of the samples with lesions indefinite for dysplasia, 55.6% (10 of 18) of the specimens with low-grade dysplasia, and 75% (3 of 4) of the specimens with high-grade dysplasia.
Conclusions: These data suggest that p16 promoter hypermethylation is a common mechanism of p16 gene inactivation during neoplastic progression in Barrett's esophagus.
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http://dx.doi.org/10.1016/s0016-5085(98)70016-2 | DOI Listing |
Diagn Pathol
January 2025
Department of Pathology, First Faculty of Medicine, Charles University and General University Hospital in Prague, Studničkova 2, Prague, 12800, Czech Republic.
Background: Juvenile granulosa cell tumor (JGCT) of the ovary is a rare tumor with distinct clinicopathological and hormonal features primarily affecting young women and children. We conducted a complex clinicopathological, immunohistochemical, and molecular analysis of five cases of JGCT.
Methods: The immunohistochemical examination was performed with 32 markers, including markers that have not been previously investigated.
FEBS J
January 2025
Université d'Angers, Inserm, CNRS, CRCI2NA, ICO, Angers, France.
Senescence is a tumor suppressor mechanism triggered by oncogene expression and chemotherapy treatment. It orchestrates a definitive cessation of cell proliferation through the activation of the p53-p21 and p16-Rb pathways, coupled with the compaction of proliferative genes within heterochromatin regions. Some cancer cells have the ability to elude this proliferative arrest but the signaling pathways involved in circumventing senescence remain to be characterized.
View Article and Find Full Text PDFNeoplasia
December 2024
Department of Pathology, Ajou University School of Medicine, Suwon 16499, Republic of Korea. Electronic address:
Glioblastoma, isocitrate dehydrogenase (IDH)-wildtype (GBM), is the most malignant brain tumor in adults, with limited therapeutic intervention. Previous studies have identified a few prognostic markers for GBM, including the methylation status of O-methylguanine-DNA methyltransferase (MGMT) promoter, TERT promoter mutation, EGFR amplification, and CDKN2A/2B deletion. However, the classification of GBM remains incomplete, necessitating a comprehensive analysis.
View Article and Find Full Text PDFClin Appl Thromb Hemost
December 2024
Department of Hematology and Transfusion sciences, School of Allied Medical Sciences, Tehran University of Medical sciences, Tehran, Iran.
Objective: DNA methylation, as an epigenetic alteration, plays an essential role in the development of atherosclerosis and venous thrombosis. E-cadherin, a tumor suppressor gene and adhesion molecule, has a crucial function in platelet aggregation and hemostasis. P16, a cell cycle regulator, is involved in venous thrombosis.
View Article and Find Full Text PDFInt J Mol Sci
November 2024
Department of Biophysics of Environmental Pollution, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska Str. 141/143, 90-236 Lodz, Poland.
The aim of the present study was to investigate the concentration- and size-dependent effects of non-functionalized polystyrene nanoparticles (PS-NPs) of varying diameters (29 nm, 44 nm, and 72 nm) on specific epigenetic modifications and gene expression profiles related to carcinogenesis in human peripheral blood mononuclear cells (PBMCs) in vitro. This in vitro human-cell-based model is used to investigate the epigenetic effect of various environmental xenobiotics. PBMCs were exposed to PS-NPs at concentrations ranging from 0.
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