OLFM4 and MALT lymphoma: Subsequently, we conducted real-time PCR validation in all Hp-negative gastric MALT lymphoma patients and found that OLFM4 was significantly upregulated in the CR group, and NANOG was significantly upregulated in the NC group, suggesting that these genes may be predictive factors for the efficacy of eradication therapy in Hp-negative gastric MALT lymphoma.