Consistent with our previous study showing that Hp-negative gastric MALT lymphoma, which is considered to be caused by NHPH infection, responds well to eradication therapy [9], the results suggest that some types of bacterial infection, including NHPH, may be involved in the pathogenesis of Hp-negative gastric MALT lymphoma that responds to eradication therapy with antibiotics. The gene discussed is HP; the disease is bacterial infectious disease.