Genetic alterations in benign lesions: chronic gastritis and gastric ulcer.
OBJECTIVE
To investigate the occurrence of chromosome 3, 7, 8, 9, and 17 aneuploidies, TP53 gene deletion and p53 protein expression in chronic gastritis, atrophic gastritis and gastric ulcer, and their association with H pylori infection.


METHODS
Gastric biopsies from normal mucosa (NM, n=10), chronic gastritis (CG, n=38), atrophic gastritis (CAG, n=13) and gastric ulcer (GU, n=21) were studied using fluorescence in situ hybridization (FISH) and immunohistochemical assay. A modified Giemsa staining technique and PCR were used to detect H pylori. An association of the gastric pathologies and aneuploidies with H pylori infection was assessed.


RESULTS
Aneuploidies were increasingly found from CG (21%) to CAG (31%) and to GU (62%), involving mainly monosomy and trisomy 7, trisomies 7 and 8, and trisomies 7, 8 and 17, respectively. A significant association was found between H pylori infection and aneuploidies in CAG (P=0.0143) and GU (P=0.0498). No TP53 deletion was found in these gastric lesions, but p53-positive immunoreactivity was detected in 45% (5/11) and 12% (2/17) of CG and GU cases, respectively. However, there was no significant association between p53 expression and H pylori infection.


CONCLUSIONS
The occurrence of aneuploidies in benign lesions evidences chromosomal instability in early stages of gastric carcinogenesis associated with H pylori infection, which may confer proliferative advantage. The increase of p53 protein expression in CG and GU may be due to overproduction of the wild-type protein related to an inflammatory response in mucosa.
Departamento de Biologia, UNESP, Campus de São José do Rio Preto, Rua Cristóvão Colombo 2265, Jardim Nazareth, CEP:15054-000-São José do Rio Preto, SP-Brazil.
Ana Cristina
AC
Gobbo César
Marília
M
de Freitas Calmon
Patrícia Maluf
PM
Cury
Alaor
A
Caetano
Aldenis Albaneze
AA
Borim
Ana Elizabete
AE
Silva
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000782:Aneuploidy; D002675:Child, Preschool; D002908:Chronic Disease; D005260:Female; D005756:Gastritis / Q000235:genetics*; D017353:Gene Deletion; D016158:Genes, p53; D016481:Helicobacter Infections / Q000235:genetics; D016480:Helicobacter pylori; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008875:Middle Aged; D013276:Stomach Ulcer / Q000235:genetics*; D016159:Tumor Suppressor Protein p53 / Q000032:analysis
D016159:Tumor Suppressor Protein p53