[目的]探讨REG4在胃癌早期诊断和预后中的作用。[方法]采用免疫组化方法对有完整随访资料的96例胃癌手术切除标本中REG4蛋白表达进行检测;另采用ELISA法对45例胃癌患者血清中REG4蛋白进行测定,并同时以化学发光法检测其血清CEA、CA199浓度。[结果]96例胃癌中,低分化组、淋巴结转移组、远处转移组及TNM分期Ⅲ+Ⅳ期组的REG4蛋白阳性率分别高于高分化组(P=0.002)、无淋巴转移组(P=0.005)、无远处转移组(P=0.003)和TNM分期Ⅰ+Ⅱ期组(P=0.005);REG4蛋白表达阳性组的平均生存时间低于阴性组(P<0.05)。45例胃癌患者中血清REG4的平均浓度显著高于正常人(P=0.004)。REG4诊断阳性率在TNM分期Ⅰ期分别高于CEA(P=0.013)和CA199(P=0.000);Ⅱ期高于CEA(P=0.015)。[结论]REG4蛋白表达可作为胃癌预后的一个指标。血清REG4较CEA和CA199对胃癌有更好的早期诊断价值。 [Objective] To investigate the role of REG4 in the early diagnosis and prognosis of gastric cancer. [Method] The expression of REG4 protein in 96 specimens of gastric cancer with complete follow-up data was detected by immunohistochemical method. The REG4 protein in serum of 45 patients with gastric cancer was detected by ELISA, and the chemiluminescence method Serum CEA, CA199 concentrations. [Results] The positive rates of REG4 protein in 96 poorly differentiated, lymph node metastasis, distant metastasis and TNM stage Ⅲ + Ⅳ groups were significantly higher than those in well differentiated group (P = 0.002), lymphoid metastasis group (P = 0.005), no distant metastasis group (P = 0.003) and TNM stage Ⅰ + Ⅱ group (P = 0.005). The average survival time of REG4 protein positive group was lower than that of negative group (P <0.05). The average concentration of serum REG4 in 45 patients with gastric cancer was significantly higher than that in normal people (P = 0.004). The positive rate of REG4 in TNM stage Ⅰ was higher than that in CEA (P = 0.013) and CA199 (P = 0.000), and in stage Ⅱ was higher than that in CEA (P = 0.015). [Conclusion] REG4 protein expression can be used as an indicator of gastric cancer prognosis. Serum REG4 than CEA and CA199 on gastric cancer have a better early diagnostic value.