Serum Helicobacter pylori KatA and AhpC antibodies as novel biomarkers for gastric cancer.
OBJECTIVE
To investigate catalase (KatA) and alkyl hydroperoxide reductase (AhpC) antibodies of Helicobacter pylori as biomarkers for gastric cancer (GC).


METHODS
This study included 232 cases and 264 controls. Recombinant KatA and AhpC proteins were constructed and the levels of antibodies were tested by indirect enzyme-linked immunosorbent assay (ELISA). Logistic regression was applied to analyze the relationships between KatA, AhpC and GC. The χ(2) trend test was used to evaluate the dose-response relationships between serum KatA and AhpC antibody levels and GC. Receiver operating characteristic (ROC) curve was used to evaluate the screening accuracy of KatA and AhpC as biomarkers. Combined analysis was used to observe screening accuracy of predictors for GC.


RESULTS
In all subjects, the association between KatA and AhpC and GC risk was significant (P < 0.001) with odds ratio (OR) = 12.84 (95%CI: 7.79-21.15) and OR = 2.4 (95%CI: 1.55-3.73), respectively. KatA and AhpC antibody levels were strongly related to GC risk with a dose-dependent effect (P for trend < 0.001). The area under the ROC (AUC) for KatA was 0.806, providing a sensitivity of 66.81% and specificity of 86.36%; and the AUC for AhpC was 0.615, with a sensitivity of 75.65% and specificity of 45.49%. The AUC was 0.906 for KatA and flagella protein A (FlaA) combined analysis.


CONCLUSIONS
Serum KatA and AhpC antibodies are associated with GC risk and KatA may serve as a biomarker for GC. KatA/FlaA combined analysis improved screening accuracy.
Bing Zhang, Hai-Lin Li, Fang Guo, Xi-Yun Ren, Hai-Bo Zhou, Ya-Shuang Zhao, Wen-Jing Tian, Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin 150081, Heilongjiang Province, China.
Bing
B
Zhang
Bing Zhang, Hai-Lin Li, Fang Guo, Xi-Yun Ren, Hai-Bo Zhou, Ya-Shuang Zhao, Wen-Jing Tian, Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin 150081, Heilongjiang Province, China.
Hai-Lin
HL
Li
Bing Zhang, Hai-Lin Li, Fang Guo, Xi-Yun Ren, Hai-Bo Zhou, Ya-Shuang Zhao, Wen-Jing Tian, Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin 150081, Heilongjiang Province, China.
Qing
Q
Fan
Bing Zhang, Hai-Lin Li, Fang Guo, Xi-Yun Ren, Hai-Bo Zhou, Ya-Shuang Zhao, Wen-Jing Tian, Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin 150081, Heilongjiang Province, China.
Fang
F
Guo
Bing Zhang, Hai-Lin Li, Fang Guo, Xi-Yun Ren, Hai-Bo Zhou, Ya-Shuang Zhao, Wen-Jing Tian, Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin 150081, Heilongjiang Province, China.
Xi-Yun
XY
Ren
Bing Zhang, Hai-Lin Li, Fang Guo, Xi-Yun Ren, Hai-Bo Zhou, Ya-Shuang Zhao, Wen-Jing Tian, Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin 150081, Heilongjiang Province, China.
Hai-Bo
HB
Zhou
Bing Zhang, Hai-Lin Li, Fang Guo, Xi-Yun Ren, Hai-Bo Zhou, Ya-Shuang Zhao, Wen-Jing Tian, Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin 150081, Heilongjiang Province, China.
Ji-Wei
JW
Zhu
Bing Zhang, Hai-Lin Li, Fang Guo, Xi-Yun Ren, Hai-Bo Zhou, Ya-Shuang Zhao, Wen-Jing Tian, Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin 150081, Heilongjiang Province, China.
Ya-Shuang
YS
Zhao
Bing Zhang, Hai-Lin Li, Fang Guo, Xi-Yun Ren, Hai-Bo Zhou, Ya-Shuang Zhao, Wen-Jing Tian, Department of Epidemiology, College of Public Health, Harbin Medical University, Harbin 150081, Heilongjiang Province, China.
Wen-Jing
WJ
Tian
D000907:Antibodies, Bacterial / Q000097:blood*; D019540:Area Under Curve; D001426:Bacterial Proteins / Q000276:immunology*; D014408:Biomarkers, Tumor / Q000097:blood*; D016022:Case-Control Studies; D002374:Catalase / Q000276:immunology*; D016009:Chi-Square Distribution; D004797:Enzyme-Linked Immunosorbent Assay; D016481:Helicobacter Infections / Q000097:blood* / Q000175:diagnosis / Q000276:immunology / Q000382:microbiology; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans; D016015:Logistic Models; D016017:Odds Ratio; D010544:Peroxidases / Q000276:immunology*; D011237:Predictive Value of Tests; D012372:ROC Curve; D015203:Reproducibility of Results; D012698:Serologic Tests; D013274:Stomach Neoplasms / Q000097:blood* / Q000175:diagnosis / Q000276:immunology / Q000382:microbiology
D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D014408:Biomarkers, Tumor; D010544:Peroxidases; C508531:ahpC protein, Helicobacter pylori; D002374:Catalase; C508532:katA protein, Helicobacter pylori
Alkyl hydroperoxide reductase; Case-control study; Catalase; Gastric cancer; Helicobacter pylori; Serum antibody