Gastric lymphoma: association withHelicobacter pyloriouter membrane protein Q (HopQ) and cytotoxic-pathogenicity activity island (CPAI) genes

Abstract

SUMMARYB-cell non-Hodgkin lymphoma (B-cell NHL) is the second commonest malignancy in the stomach. We determined the distribution ofHelicobacter pyloriouter membrane protein Q (HopQ) allelic type, cytotoxin-associated gene (cag)-pathogenicity activity island (cag-PAI) and vacuolation activating cytotoxin A (vacA) genes, respectively, in patients with B-cell NHL. We also compared them with their distribution in non-ulcer dyspepsia (NUD).H. pyloriwas cultured from gastric biopsy tissue obtained at endoscopy. Polymerase chain reaction was performed. Of 170 patients enrolled, 114 (63%) had NUD and 56 (37%) had B-cell NHL. HopQ type 1 was positive in 66 (58%) in NUD compared with 46 (82%) (P= 0·002) in B-cell NHL; HopQ type 2 was positive in 93 (82%) with NUD compared with 56 (100%) (P< 0·001) in B-cell NHL. Multiple HopQ types were present in 46 (40%) in NUD compared with 46 (82%) (P< 0·001) in B-cell NHL. CagA was positive in 48 (42%) in NUDvs. 50 (89%) (P< 0·001) in B-cell NHL; cagT was positive in 35 (31%) in NUDvs. 45 (80%) (P< 0·001) in B-cell NHL; left end of thecagAgene (LEC)1 was positive in 23 (20%) in NUDvs. 43 (77%) (P< 0·001) in B-cell NHL. VacAs1am1 positive in B-cell NHL in 48 (86%) (P< 0·001)vs. 50 (44%) in NUD, while s1am2 was positive in 20 (17%) in NUDvs. 46 (82%) (P< 0·001) in B-cell NHL.H. pyloristrains with multiple HopQ allelic types, truncated cag-PAI evidenced by expression of cagA, cagT and cag LEC with virulent vacAs1 alleles are associated with B-cell NHL development.