Low-Positive Antibody Titer againstHelicobacter pyloriCytotoxin-Associated Gene A (CagA) May Predict Future Gastric Cancer Better Than Simple Seropositivity againstH. pyloriCagA or againstH. pylori

Autor: Masazumi Akahoshi, Nobuaki Hattori, Harry M. Cullings, Masayuki Hakoda, Gen Suzuki, Saeko Fujiwara, Eiichi Tahara, Shinsuke Matsuura, Kazunori Kodama
Rok vydání: 2007
Předmět:
Zdroj: Cancer Epidemiology, Biomarkers & Prevention. 16:1224-1228
ISSN: 1538-7755
1055-9965
Popis: Background: To investigate the IgG antibody titer against Helicobacter pylori CagA as a risk factor for future noncardia gastric cancer.Methods: A nested case-control study was done in the longitudinal cohort of atomic bomb survivors using stored sera before diagnosis (mean, 2.3 years). Enrolled were 299 cancer cases and 3 controls per case selected from cohort members matched on age, gender, city, and time and type of serum storage and countermatched on radiation dose.Results: H. pylori IgG seropositive with CagA IgG low titer was the strongest risk factor for noncardia gastric cancer [relative risk (RR), 3.9; 95% confidence interval (95% CI), 2.1-7.0; P < 0.001], especially for intestinal-type tumor (RR, 9.9, 95% CI, 3.5-27.4; P < 0.001), compared with other risk factors, H. pylori IgG seropositive with CagA IgG negative (RR, 2.2; 95% CI, 1.3-3.9; P = 0.0052), H. pylori IgG seropositive with CagA IgG high titer (RR, 2.0; 95% CI, 1.3-3.2; P = 0.0022), chronic atrophic gastritis (RR, 2.4; 95% CI, 1.8-3.3; P < 0.001), current smoking (RR, 2.3; 95% CI, 1.4-3.5; P < 0.001), or radiation dose (RR, 2.1; 95% CI, 1.2-3.1; P = 0.00193). Current smoking showed significantly higher risk for diffuse-type than intestinal-type tumors (P = 0.0372). Radiation risk was significant only for nonsmokers, all noncardia, and diffuse-type gastric cancers.Conclusions: A low CagA IgG titer is a useful biomarker to identify a high-risk group and it also provides a clue to understanding host-pathogen interaction. (Cancer Epidemiol Biomarkers Prev 2007;16(6):1224–8)
Databáze: OpenAIRE