title: Carcinogenic Helicobacter pylori in gastric pre-cancer and cancer lesions: association with tobacco-chewing.
abstract: OBJECTIVE
  To investigate the low gastric cancer incidence rate relative to the highly prevalent Helicobacter pylori (H. pylori) infection; data relevant to H. pylori infection during gastric carcinogenesis in Indian patients is currently lacking.
  
  
  METHODS
  The present study examines the prevalence of H. pylori infection in DNA derived from 156 endoscopic gastric biopsies of different disease groups that represent gastric pre-cancer [intestinal metaplasia (n = 15), dysplasia (n = 15)], cancer [diffuse adenocarcinoma (n = 44), intestinal adenocarcinoma (n = 21)], and symptomatic but histopathologically-normal controls (n = 61). This was done by generic ureC polymerase chain reaction (PCR) and cagA-specific PCR that could specifically identify the carcinogenic H. pylori strain.
  
  
  RESULTS
  Our analysis showed the presence of H. pylori infection in 61% of symptomatic histopathologically-normal individuals, however only 34% of control tissues were harboring the cagA(+) H. pylori strain. A similar proportion of H. pylori infection (52%) and cagA (26%) positivity was observed in the tumor tissue of the gastric cancer group. In comparison, H. pylori infection (90%) and cagA positivity (73%) were the highest in gastric pre-cancer lesions. In relation to tobacco and alcohol abuse, H. pylori infection showed an association with tobacco chewing, whereas we did not observe any association between tobacco smoking or alcohol abuse with prevalence of H. pylori infection in the tissue of any of the patient groups studied.
  
  
  CONCLUSIONS
  High incidence of H. pylori infection and carcinogenic cagA positive strain in pre-cancer lesions during gastric carcinogenesis may be associated with the habit of chewing tobacco.
authors.affiliation: Arvind Pandey, Sutapa Mahata, Kanchan Vishnoi, Shirish Shukla, Suresh Hedau, Ravi Mehrotra, Alok C Bharti, Division of Molecular Oncology, Institute of Cytology and Preventive Oncology (ICMR), Noida 201301, India.
authors.forename: Arvind
authors.initials: A
authors.lastname: Pandey
authors.affiliation: Arvind Pandey, Sutapa Mahata, Kanchan Vishnoi, Shirish Shukla, Suresh Hedau, Ravi Mehrotra, Alok C Bharti, Division of Molecular Oncology, Institute of Cytology and Preventive Oncology (ICMR), Noida 201301, India.
authors.forename: Satyendra Chandra
authors.initials: SC
authors.lastname: Tripathi
authors.affiliation: Arvind Pandey, Sutapa Mahata, Kanchan Vishnoi, Shirish Shukla, Suresh Hedau, Ravi Mehrotra, Alok C Bharti, Division of Molecular Oncology, Institute of Cytology and Preventive Oncology (ICMR), Noida 201301, India.
authors.forename: Sutapa
authors.initials: S
authors.lastname: Mahata
authors.affiliation: Arvind Pandey, Sutapa Mahata, Kanchan Vishnoi, Shirish Shukla, Suresh Hedau, Ravi Mehrotra, Alok C Bharti, Division of Molecular Oncology, Institute of Cytology and Preventive Oncology (ICMR), Noida 201301, India.
authors.forename: Kanchan
authors.initials: K
authors.lastname: Vishnoi
authors.affiliation: Arvind Pandey, Sutapa Mahata, Kanchan Vishnoi, Shirish Shukla, Suresh Hedau, Ravi Mehrotra, Alok C Bharti, Division of Molecular Oncology, Institute of Cytology and Preventive Oncology (ICMR), Noida 201301, India.
authors.forename: Shirish
authors.initials: S
authors.lastname: Shukla
authors.affiliation: Arvind Pandey, Sutapa Mahata, Kanchan Vishnoi, Shirish Shukla, Suresh Hedau, Ravi Mehrotra, Alok C Bharti, Division of Molecular Oncology, Institute of Cytology and Preventive Oncology (ICMR), Noida 201301, India.
authors.forename: Sri Prakash
authors.initials: SP
authors.lastname: Misra
authors.affiliation: Arvind Pandey, Sutapa Mahata, Kanchan Vishnoi, Shirish Shukla, Suresh Hedau, Ravi Mehrotra, Alok C Bharti, Division of Molecular Oncology, Institute of Cytology and Preventive Oncology (ICMR), Noida 201301, India.
authors.forename: Vatsala
authors.initials: V
authors.lastname: Misra
authors.affiliation: Arvind Pandey, Sutapa Mahata, Kanchan Vishnoi, Shirish Shukla, Suresh Hedau, Ravi Mehrotra, Alok C Bharti, Division of Molecular Oncology, Institute of Cytology and Preventive Oncology (ICMR), Noida 201301, India.
authors.forename: Suresh
authors.initials: S
authors.lastname: Hedau
authors.affiliation: Arvind Pandey, Sutapa Mahata, Kanchan Vishnoi, Shirish Shukla, Suresh Hedau, Ravi Mehrotra, Alok C Bharti, Division of Molecular Oncology, Institute of Cytology and Preventive Oncology (ICMR), Noida 201301, India.
authors.forename: Ravi
authors.initials: R
authors.lastname: Mehrotra
authors.affiliation: Arvind Pandey, Sutapa Mahata, Kanchan Vishnoi, Shirish Shukla, Suresh Hedau, Ravi Mehrotra, Alok C Bharti, Division of Molecular Oncology, Institute of Cytology and Preventive Oncology (ICMR), Noida 201301, India.
authors.forename: Manisha
authors.initials: M
authors.lastname: Dwivedi
authors.affiliation: Arvind Pandey, Sutapa Mahata, Kanchan Vishnoi, Shirish Shukla, Suresh Hedau, Ravi Mehrotra, Alok C Bharti, Division of Molecular Oncology, Institute of Cytology and Preventive Oncology (ICMR), Noida 201301, India.
authors.forename: Alok C
authors.initials: AC
authors.lastname: Bharti
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000942:Antigens, Bacterial / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D001706:Biopsy; D016022:Case-Control Studies; D002648:Child; D005260:Female; D005838:Genotype; D016481:Helicobacter Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D016480:Helicobacter pylori / Q000235:genetics / Q000472:pathogenicity*; D006801:Humans; D015994:Incidence; D007194:India / Q000453:epidemiology; D008297:Male; D008679:Metaplasia; D008875:Middle Aged; D010641:Phenotype; D011230:Precancerous Conditions / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D015995:Prevalence; D012307:Risk Factors; D013270:Stomach / Q000382:microbiology / Q000473:pathology; D013274:Stomach Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D064424:Tobacco Use / Q000009:adverse effects* / Q000453:epidemiology*; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C080866:cagA protein, Helicobacter pylori
keywords: CagA; Dysplasia; Gastric adenocarcinoma; Intestinal metaplasia; Tobacco chewing; UreC