Background and Objective: Helicobacter pylori is a human-stomach-dwelling organism that causes many gastric illnesses, including
gastritis,
ulcer, and
gastric cancer. The purpose of the study was to perform differential proteomic analysis on H. pylori isolates from
gastritis,
ulcer, and
gastric cancer patients. Materials and Methods: H. pylori was isolated from antrum and fundus biopsies obtained from patients who visited the Department of Gastroenterology. Using nano-LC-QTOF MS/MS analysis, differentially regulated
proteins were identified through
proteome profiling of pooled samples of H. pylori isolated from
gastritis,
ulcer, and
gastric cancer patients. Antigenic scores and cellular localization of
proteins were determined using additional prediction tools. Results: A total of 14 significantly regulated
proteins were identified in H. pylori isolated from patients with either
gastritis,
ulcer, or
gastric cancer. Comparative analysis of groups revealed that in the case of
cancer vs.
gastritis, six
proteins were overexpressed, out of which two
proteins, including
hydrogenase maturation factor (hypA) and
nucleoside diphosphate kinase (ndk) involved in bacterial colonization, were only upregulated in isolates from
cancer patients. Similarly, in
cancer vs.
ulcer, a total of nine
proteins were expressed. Sec-independent
protein translocase
protein (tatB), involved in protein translocation, and
pseudaminic acid synthase I (pseI), involved in the synthesis of functional flagella, were upregulated in
cancer, while hypA and ndk were downregulated. In
ulcer vs.
gastritis, eight
proteins were expressed. In this group, tatB was overexpressed. A reduction in
thioredoxin peroxidase (
bacterioferritin co-migratory
protein (bcp)) was observed in
ulcer vs.
gastritis and
cancer vs.
ulcer. Conclusion: Our study suggested three discrete
protein signatures, hypA, tatB, and bcp, with differential expression in
gastritis,
ulcer, and
cancer.
Protein expression profiles of H. pylori isolated from patients with these
gastric diseases will help to understand the virulence and pathogenesis of H. pylori.