Altered expression of Krüppel-like factor 4 and β-catenin in human gastric cancer

Department of General Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
Oncology letters (Impact Factor: 1.55). 05/2012; 3(5):1017-1022. DOI: 10.3892/ol.2012.619
Source: PubMed


The effects of the interaction between KLF4 and β-catenin may be significant in human carcinogenesis and tumor development. This study aimed to determine whether the expression of KLF4 and β-catenin in gastric cancer tissues is associated with clinicopathological characteristics. Western blot analysis and immunohistochemistry were performed to detect KLF4 and β-catenin expression in tumor and corresponding non-cancerous tissues from 49 patients. The data revealed that KLF4 expression was significantly reduced in gastric cancer tissues compared with normal tissues. By contrast, the expression of the β-catenin protein was significantly increased in all tumor tissues, but was not expressed in distant normal mucosae. The altered expression of the KLF4 and β-catenin proteins was associated with advanced tumor stage and gastric cancer. In addition, the expression of the KLF4 and β-catenin proteins was inversely associated in moderately differentiated human gastric cancers. This study showed that β-catenin expression is significantly increased and KLF4 protein expression is markedly decreased in gastric cancer tissues, thus showing that the expression of KLF4 is inversely correlated with that of β-catenin in gastric cancer. The altered expression of the two proteins is associated with advanced tumor stage in gastric cancer.

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    • "The KLF4 protein contains both activator and repressor domains, and can function as a positive or negative regulator of gene expression [27-29]. Oncogenic effects of KLF4 have been reported in breast, skin, and lung cancers [14,15,30]. "
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