No abstract

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.

Background: Non-coding RNA molecules, such as microRNAs, may play an important role in carcinogenesis. Recent studies have indicated that microRNAs are involved in initiation and progression of various malignancies. However, little work has been done to compare the microRNA expression patterns in oral cancer. In this study, we constructed an animal model of oral squamous cell carcinoma to investigate expression profiles of microRNAs in oral carcinogenesis.

BackgroundTumor metastasis is one of the leading causes of poor prognosis for colorectal cancer (CRC) patients. Loss of Smad4 contributes to aggression process in many human cancers. However, the underlying precise mechanism of aberrant Smad4 expression in CRC development is still little known.ResultsmiR-20a-5p negatively regulated Smad4 by directly targeting its 3′UTR in human colorectal cancer cells. miR-20a-5p not only promoted CRC cells aggression capacity in vitro and liver metastasis in vivo, but also promoted the epithelial-to-mesenchymal transition process by downregulating Smad4 expression. In addition, tissue microarray analysis obtained from 544 CRC patients’ clinical characters showed that miR-20a-5p was upregulated in human CRC tissues, especially in the tissues with metastasis. High level of miR-20a-5p predicted poor prognosis in CRC patients.MethodsFive miRNA target prediction programs were applied to identify potential miRNA(s) that target(s) Smad4 in CRC. Luciferase reporter assay and transfection technique were used to validate the correlation between miR-20a-5p and Smad4 in CRC. Wound healing, transwell and tumorigenesis assays were used to explore the function of miR-20a-5p and Smad4 in CRC progression in vitro and in vivo. The association between miR-20a-5p expression and the prognosis of CRC patients was evaluated by Kaplan–Meier analysis and multivariate cox proportional hazard analyses based on tissue microarray data.ConclusionsmiR-20a-5p, as an onco-miRNA, promoted the invasion and metastasis ability by suppressing Smad4 expression in CRC cells, and high miR-20a-5p predicted poor prognosis for CRC patients, providing a novel and promising therapeutic target in human colorectal cancer.