Expression microarrays are widely used for investigating the candidate molecular targets in human cancer. While genome-wide expression signatures screened by gene set enrichment analysis (GSEA) were not performed in Chinese gastric cancer (GC). To gain new molecular targets for GC, GSEA analysis was performed. In the present study, GSEA were used to pick out differentially expressed gene sets of our database. Total RNA of paired tissue samples (n = 48) and a tissue microarray containing 132 paired tissues were used to further validate expression levels of INHBA and its correction with clinicopathological factors. Upregulated INHBA expression in gastric cancer was screened and further confirmed by qPCR and immunostaining analysis. Increased INHBA expression was significantly correlated with the diameter of cancer and depth of tumor invasion. Patients with higher expression levels of INHBA had a shorter disease-free survival rate. It was effective to gain new molecular targets for GC by GSEA analysis. INHBA may be a poor survival indicator of GC.

Abstract. Colon cancer is one of the most frequently diagnosed cancer and the third most fatal malignancy worldwide. HOTAIR, a cancer-associated long non-coding RNA (lncRNA), is a powerful biomarker of metastasis and poor prognosis in a diverse group of cancers. Nevertheless, an understanding of how HOTAIR is involved in colon cancer progression is limited. In the present study, we hypothesized that HOTAIR plays a crucial role in colon cancer development. We evaluated the expression of HOTAIR in 120 colon cancer samples, matched adjacent non-tumor mucosa and 32 lymph node metastasis tissues by real-time PCR. Increased HOTAIR expression was significantly correlated with the depth of tumor invasion, lymph node metastasis, organ metastasis, histological differentiation, vascular invasion and advanced tumor stage. Patients with high HOTAIR expression had higher recurrence rates and reduced metastasis-free and overall survival than patients with low HOTAIR expression. Moreover, our findings revealed that HOTAIR had a limited effect on cell proliferation but significantly promoted colon cancer cell migration and invasion in vitro. Depletion of HOTAIR increased the expression of E-cadherin while concomitantly decreasing expression of vimentin and MMP9. Hence, HOTAIR may be another pleiotropic modulator participating in epithelial-mesenchymal transition (EMT). These results indicate that HOTAIR may also be a valuable predictor for colon cancer management; furthermore, this lncRNA may be a potential target for cancer prevention and treatment.

Purpose IFITM3, an interferon-inducible gene, is overexpressed in human colorectal cancer. In this study, we sought to determine the clinical significance and underlying mechanisms of its dysregulated expression in human colon tumor specimens and murine models of this disease. Experimental Design IFITM3 expression in a tissue microarray of tumor and matched normal colon tissue specimens and lymph node metastasis specimens obtained from 203 patients with colon cancer was measured immunohistochemically. Results IFITM3 was expressed at higher levels in colon tumors and, particularly, nodal metastases than in normal colon tissue. A Cox proportional hazards model showed that IFITM3 expression was an independent prognostic factor for disease-free survival in patients with colon cancer. Knockdown of IFITM3 expression by a specific small interfering RNA significantly suppressed the proliferation, colony formation, migration, and invasion of colon cancer cells in vitro and tumor growth and metastasis in a xenograft model. Restored expression of KLF4, a putative tumor suppressor, downregulated IFITM3 expression in colon cancer cells in vitro. Two KLF4-binding sites in the IFITM3 promoter bound specifically to KLF4 protein in a chromatin immunoprecipitation assay and promoter mutagenesis analyses. Specific deletion of KLF4 led to IFITM3 overexpression in colon mucosa in Villin-Cre+;Klf4fl/fl mice. An inverse correlation between loss of KLF4 expression and IFITM3 overexpression was evident in human colon tumors. Conclusion these clinical and mechanistic findings indicate that IFITM3 is a direct transcriptional target of KLF4 and that dysregulated KLF4 expression leads to aberrant IFITM3 expression, thus contributing to colon cancer progression and metastasis.