title: Helicobacter pylori infection and a P53 codon 72 single nucleotide polymorphism: a reason for an unexplained Asian enigma.
abstract: OBJECTIVE
  P53, the most commonly mutated tumor suppressor gene in all types of human cancer, is involved in cell cycle arrest and control of apoptosis. Although p53 contains several polymorphic sites, the codon 72 polymorphism is by far more common. There are divergent reports but many studies suggest p53 pro/pro SNP may be associated with susceptibility to developing various cancers in different regions of the world. The present study aimed to find any correlation between H. pylori infection and progression of carcinogenesis, by studying apoptosis and the p53 gene in gastric biopsies from north Indian population.
  
  
  METHODS
  A total of 921 biopsies were collected and tested for prevalence of H. pylori by rapid urease test (RUT), imprint cytology and histology. Apoptosis was studied by the TUNEL method. Analysis of p53 gene polymorphism at codon 72 was accomplished by PCR using restriction enzyme BstU1.
  
  
  METHODS
  Out of 921 samples tested 56.7% (543) were H. pylori positive by the three techniques. The mean apoptotic index (AI) in the normal group was 2.12, while gastritis had the maximum 4.24 followed by gastric ulcer 2.28, gastropathy 2.22 and duodenal ulcer 2.08. Mean AI in cases with gastric cancer (1.72) was less than the normal group. The analysis of p53 72 SNP revealed that p53 (Arg/Arg), (Pro /Arg) variant are higher (40.59% and 33.66%) as compared to p53 pro/pro variant (25.74%) in the healthy population.
  
  
  CONCLUSIONS
  The North Indian population harbors Arg or Pro/Arg SNP that is capable of withstanding stress conditions; this may be the reason of low incidence of gastric disease in spite of high infection with H. pylori. There was no significant association with H. pylori infection and AI. However, there is increased apoptosis in gastritis which may occur independent of H. pylori or p53 polymorphism.
authors.affiliation: Pandey Research, South Dakota, USA E-mail : renuisindian@gmail.com, renu.lasers@gmail.com.
authors.forename: Renu
authors.initials: R
authors.lastname: Pandey
authors.forename: Vatsala
authors.initials: V
authors.lastname: Misra
authors.forename: Sri Prakash
authors.initials: SP
authors.lastname: Misra
authors.forename: Manisha
authors.initials: M
authors.lastname: Dwivedi
authors.forename: Alok
authors.initials: A
authors.lastname: Misra
mesh_terms: D000328:Adult; D017209:Apoptosis; D016022:Case-Control Studies; D003062:Codon / Q000235:genetics; D004381:Duodenal Ulcer / Q000209:etiology* / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D005756:Gastritis / Q000209:etiology* / Q000473:pathology; D020022:Genetic Predisposition to Disease; D005838:Genotype; D016481:Helicobacter Infections / Q000150:complications* / Q000235:genetics; D016480:Helicobacter pylori / Q000302:isolation & purification; D006801:Humans; D007194:India; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011379:Prognosis; D013274:Stomach Neoplasms / Q000209:etiology* / Q000473:pathology; D013276:Stomach Ulcer / Q000209:etiology* / Q000473:pathology; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*; D055815:Young Adult
chemical_list: D003062:Codon; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53