A C to T polymorphism of Urokinase Plasminogen Activator (P141L) is Associated with Helicobacter pylori Infection

Urokinase plasminogen activator (uPA) plays an important role in tumor invasion and certain inflammatorydiseases. However, few studies have paid attention to how the uPA is associated with Helicobacter pylori infectionand gastric atrophy. This study investigated associations of a C-to-T polymorphism of uPA (P141L, rs2227564) inexon 6 in 454 Japanese health checkup examinees (126 males and 328 females) aged 35 to 85 without a history ofcancer. The uPA was genotyped by polymerase chain reaction with two-pair primers. The genotype distributionwas in Hardy-Weinberg equilibrium (p=0.52) and the frequency of the T allele was 0.239. The risk of H. pylorisero-positivity was significantly reduced with the T/T genotype; the odds ratio (OR) relative to the C/C genotypewas 0.34 (95% confidence interval [CI]: 0.14 to 0.86). Of the sero-negative subjects, 21 with atrophy were infectedwith H. pylori but lost their sero-positivity. After reclassifying them together with the sero-positive subjects, thecorresponding OR was 0.40 (95% CI: 0.16 to 1.00), confirming that the T/T genotype decreased the risk of H.pylori infection. This gene polymorphism was not associated with the risk of gastric atrophy. In conclusion, thisstudy indicated a possibility that the uPA minor homozygous genotype was associated with a reduction of H.pylori infection risk. Further studies are required to confirm these findings.