DNA methylation profile in diffuse type gastric cancer: evidence for hypermethylation of the BRCA1 promoter region in early-onset gastric carcinogenesis

Abstract

50%), followed by pl4, pl6, pl5, p73, MGMT and SEMA3B (20-49%). Hierarchical clustering analysis reveáis four groups with different clinical features. The first was characterized by hypermethylation of BRCA1 and younger age (<45 years oíd), and the second by hypermethylation of pl4 and pl6 genes, male predominance and Epstein-Barr virus infection. The third group was characterized by hypermethylation of FHIT and antrum located tumors and the fourth was not associated with any clinical variables. In normal adjacent mucosa only the p73 gene was significantly less methylated in comparison to tumor mucosa. DNA methylation identified subgroups of diffuse type gastric cáncer. Hypermethylation of BRCA1 associated with young age suggests a role in early-onset gastric carcinoma.]]>

Hypermethylation of tumor suppressor genes in gastric cancer: associations with demographic and clinicopathological characteristics

“…35 Bernal C et al detected TP73 hypermethylation status in the level of 27% in stomach cancer. 36 We found hypermethylation frequencies of PAX5 and TP73 gene in GC tissues as 7.4%.…”

Bases epigenéticas del cáncer gástrico: oportunidades para la búsqueda de nuevos biomarcadores

“…Nuestros resultados indicaron que la metilación de la región promotora de los genes BRCA1, p73, RARbeta, hMLH1, RIZI, RUNX3, MGMT y TIMP3 estaría asociado a una variante agresiva y emergente del cáncer gástrico difuso, el cáncer de células de anillo de sello 40,41 . Además, se determinó que la metilación del gen APC está asociada a mal pronóstico 42 mientras que la metilación del gen BRCA1 parece estar asociada a casos de aparición temprana 43 . Sin embargo, debido a que nuestro interés en la identificación de biomarcadores incluía la posibilidad de usar muestras de tipo no invasivo, como suero o plasma, es que evaluamos siete genes (APC, SHP1, CDH1, ER, Reprimo, SEMA3B, 3OST2) que estaban frecuentemente metilados.…”

“…El gen Reprimo (símbolo oficial RPRM) se localiza en el cromosoma 2q23.3 43 . Reprimo es inducido después de irradiación con rayos X de manera dependiente de p53, causando detención del ciclo celular en fase G2 45 .…”

Molecular Pathology of Gastritis

“…In addition, DNA metylation has been recently considered as an excellent candidate to explain how certain environmental factors may increase the risk of cancer (32). Accordingly, an emerging catalog of specific tumor suppressor genes inactivated by DNA methylation in gastrointestinal tumors has been established (33)(34)(35)(36). Most of these studies has been performed by Methylation Specific -Polymerase Chain Reaction (MS-PCR), the most popular assay for DNA methylation (37).…”