胃腺癌腹腔灌洗液多巴脱羧酶的表达分析和临床应用

Clinical significance of dopa decarboxylase expression in gastric peritoneal lavage in patients with gastric adenocarcinoma

目的:通过对胃腺癌患者的腹腔灌洗液检测多巴脱羧酶(dopa decarboxylase D D C)m R N A表达,评估D D C成为预测胃腺癌腹膜微转移的新指标的可能性.方法:收集南昌大学第二附属医院胃肠外科87例胃腺癌患者的腹腔灌洗液,应用实时荧光定量聚合酶链反应(quantitative real time polymerase chain reaction,QRT-PCR方法相对定量检测并比较DDC m RNA的表达.12例非癌症患者腹腔灌洗液作为阴性对照.结果:87例胃腺癌患者中,T1有6例,T2有14例,T3有28例,T4有39例,DDC m RNA的表达在不同T分级(浸润深度分级)DDC m RNA的相对表达值(×107)分别为:T1,168±21T2,283±87;T3,31162±4261;T4,35310±6593.非癌症组腹腔灌洗液中,DDC m RNA相对表达值(×107)为:60.28±19.00.此外D D C的表达还与组织分化程度、病理分化类型、是否有淋巴结转移等有关系.胃腺癌腹腔灌洗液应用常规腹腔细胞学检查(conventional intraperitoneal cytology,CY)检查,11例阳性(CY+),阳性率为13%(11/87).11例(CY+)中有9例DDC m RNA表达相对值结果高于临界值,归类于DDC+,DDC的敏感性为86%(9/11),此外,在10例T1患者和14例T2患者中DDC+为2例,且非癌症组中均未见DDC+,DDC的特异性为92%(22/24).表明腹腔灌洗液中DDC在胃腺癌不同浸润深度下差异性表达(P<0.05),具有较好的敏感性和特异性.结论:应用QRT-PCR技术可以有效检测腹腔灌洗液中DDC m RNA表达,DDC可能成为预测胃癌腹膜转移的可靠指标.

AIM： To detect the mRNA expression of dopa decarboxylase （DDC） in intraperitoneal lavage fluid from patients with gastric adenocarcinoma, and to evaluate the possibility of using DDC expression in intraperitoneal lavage fluid as a new predictor of peritonealmicrometastasis of gastric adenocarcinoma. METHODS： Intraperitoneal lavage fluid samples were collected from 87 patients with gastric adenocarcinoma treated in the Second Affiliated Hospital of Nanchang University. Quantitative real-time polymerase chain reaction （QRT-PCR） was used to detect the DDC mRNA expression in intraperitoneal lavage fluid. Intraperitoneal lavage fluid samples from 12 non-cancer patients were used as negative controls. RESULTS： In the 87 patients with gastric adenocarcinoma, the number of patients with T1, T2, T3 and T4 stage disease was 6, 14, 28 and 39, respectively. The relative expression levels （x107） of DDC mRNA in different T stages （invasion grade） were： T1, 168 ±21; T2, 283 ± 87; T3, 31162 ± 4261; T4, 35310± 6593; and 60.28 ± 19.00 in non-cancer group. The expression of DDC was also correlated with the degree of tumor differentiation, pathological type and lymph node metastasis. Conventional intraperitoneal cytology （CY） revealed positive results （CY＋） in 11 patients, and the positive rate was 13% （11/87）. In 9 of 11 CY＋ cases, the DDC mRNA expression was higher than the critical value （classified as DDC＋）, and the sensitivity of DDC detection was 86% （9/11）. In addition, only two DDC＋ cases were found in the 10 patients with T1 and 14 with T2 disease, and no DDC＋ result was observed in the non-cancer group. The DDC specificity was 92% （22/24）. Differential expression of DDC in intraperitoneal lavage fluid was noted in gastric adenocarcinoma with different depth of invasion （P 〈 0.05）. CONCLUSION： QRT-PCR can effectively detect DDC mRNA expression in intraperitoneal lavage fluid, which may become a new reliable predictor of peritoneal metastasis of gastric adenocarcinoma.