摘要
目的:探讨CLDN18表达与胃癌临床病理特征之间的关系。方法:组织芯片免疫组化染色法检测胃癌claudin-18蛋白表达,Real-time PCR法检测胃癌CLDN18 mRNA的表达。结果:胃癌组织claudin-18表达显著降低,并与组织学类型和浸润相关,肠型胃癌和浸润在肌层以内者其黏膜层claudin-18的下调表达率明显高于弥漫型胃癌或浸润程度超过肌层者。从黏膜层进展至侵袭前缘区,claudin-18的下调表达率逐渐升高,黏膜层claudin-18表达水平明显高于侵袭前沿区。进展期胃癌黏膜层癌组织claudin-18表达未下调者34例进展至侵袭前沿区28例转变为表达下调,其中弥漫型胃癌、浸润程度超过肌层者、有淋巴结转移者以及非贲门胃癌者发生率均高于肠型胃癌、浸润程度在肌层内者、无淋巴结转移者以及贲门胃癌者。52例胃癌黏膜层胃癌组织CLDN18 mRNA表达下调者20例,其相对表达量与浸润程度及肿瘤大小有关。结论:胃癌的进展中claudin-18表达降低,组织学类型的维持与其密切相关。
Objective:To study relationship between CLDN18 gene expression and the clinicopathologic features of gastric cancer (GC).Methods:A tissue microarray was made and immunohistochemistry was performed to detect the expression of claudin-18 protein.Real-time polymerase chain reaction was conducted to examine mRNA expression of CLDN18 gene.Results:Expression of claudin-18 protein in GC was significantly downregulated and was correlated with histologic types and extent of invasion,which was greatly decreased in the intestinal-type and intramuscular infiltration of GC than in the diffuse-type and the extramuscular extension,respectively. There was a gradual downregulation of claudin-18 expression from the mucosa to the front of the invasion.Claudin-18 expression was higher in the mucosa than at the front of invasion.Of the 34 cases with advanced GC without downregulation of claudin -18 expression in mucosa,28 had claudin-18 downregulation as GC developed to the front of the invasion.In the 28 cases,the incidences of the diffuse-type GC,extramuscular infiltration,lymph node metastasis,and non-cardiac GC were higher compared with the intestinal-type,intramuscular,non-metastatic,and cardiac GC.CLDN18 mRNA expression was downregulated in 20 of the 52 GC cases. The relative expression was associated with the infiltration and size of the tumors.Conclusion:Downregulation of claudin-18 expression is involved in the progression of disease,and in maintaining the phenotype of gastric adenocarcinoma.
引文
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