Clinicopathological and prognostic significance of microRNA-107 and its relationship to DICER1 mRNA expression in gastric cancer.
ABSTRACT microRNAs (miRNAs) are small non-coding RNAs that regulate target gene expression. It is known that miRNA-107 (miR-107) promotes cancer invasion and metastasis. However, the relationship between clinicopathological factors and the prognostic significance of miR-107 for gastric cancer patients remains elusive. In this study, we evaluated the prognostic value of miR-107 using tissue samples from gastric cancer patients. Furthermore, the relationship between miR-107 and the mRNA levels of its target gene DICER1 was examined. The expression levels of miR-107 and DICER1 mRNA in tumor tissues and adjacent normal tissues of 161 gastric cancer patients were examined (TNM stage I, 29 patients; stage II, 31 patients; stage III, 51 patients and stage IV, 50 patients). miR-107 levels were measured by Taqman microRNA assays, and DICER1 mRNA levels were measured by the Taqman real-time RT-PCR method. In the analysis by real-time PCR-based miRNA arrays using pooled RNA samples from five gastric cancer patients, expression of miR-107, miR-21, miR-196a, miR-26b, miR-9, miR-142-3p, miR-30b, miR-150, miR-191 and miR-17 was found to be upregulation. The mean expression level of miR-107 was significantly higher in the tumor tissues compared to that of normal tissues. In the comparison of clinicopathological factors, miR-107 expression showed significant association with depth of tumor invasion, lymph node metastasis and stage. In Kaplan-Meier survival curve analysis, overall survival rates (OS) and disease-free survival rates (DFS) of patients with high miR-107 expression were significantly worse than those of patients with low miR-107 expression. In the Cox multivariate analysis, it was shown that miR-107 expression in gastric cancer tissues was an independent prognostic factor for OS and DFS. Significant inverse correlations were demonstrated between miR-107 and DICER1 mRNA. Our results indicate that miR-107 may be useful as an effective biomarker for prediction of a poor prognosis in gastric cancer patients.
- SourceAvailable from: PubMed Central[show abstract] [hide abstract]
ABSTRACT: microRNAs (miRNAs) are a group of small non-coding RNAs that are ~22 (18 to 25) nucleotides (nt) long and have been associated with a variety of diseases, including cancer. Increasing evidence indicates that miRNAs are essential in the development, diagnosis, treatment and prognosis of a variety of tumors. The utility of miRNAs as biomarkers for diagnosis and of target molecules for the treatment of cancers is increasingly being recognized. With the discovery of circulating miRNAs, a non-invasive approach for the diagnosis and treatment of cancer has been identified. This review summarizes the role of miRNAs in the development of different tumors, as well as a variety of other biological events. Moreover, this review focuses on analyzing the function and mechanism of gastric cancer-related miRNAs and investigates the importance of circulating miRNAs in gastric cancer, as well as their origin. Finally, this review lists a number of the problems that must be solved prior to miRNAs being used as reliable non-invasive tools for the diagnosis, treatment and prognosis of gastric cancer.Oncology letters 09/2013; 6(3):631-641. · 0.24 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: Commensal flora plays an important role in the development of the mucosal immune system and in maintaining intestinal homeostasis. However, the mechanisms involved in regulation of host-microbiota interaction are still not completely understood. In this study, we examined how microbiota and intestinal inflammatory conditions regulate host microRNA expression and observed lower microRNA-107 (miR-107) expression in the inflamed intestines of colitic mice, compared with that in normal control mice. miR-107 was predominantly reduced in epithelial cells and CD11c(+) myeloid cells including dendritic cells and macrophages in the inflamed intestines. We demonstrate that IL-6, IFN-γ and TNF-α downregulated, whereas TGF-β promoted, miR-107 expression. In addition, miR-107 expression was higher in the intestines of germ-free mice than in mice housed under specific pathogen-free conditions, and the presence of microbiota downregulated miR-107 expression in DCs and macrophages in a MyD88- and NF-κB-dependent manner. We determined that the ectopic expression of miR-107 specifically repressed the expression of IL-23p19, a key molecule in innate immune responses to commensal bacteria. We concluded that regulation of miR-107 by intestinal microbiota and pro-inflammatory cytokine serve as an important pathway for maintaining intestinal homeostasis.European Journal of Immunology 11/2013; · 4.97 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: MicroRNA-107 (miR-107) has been demonstrated to regulate proliferation and apoptosis in many types of cancers. Nevertheless, its biological function in gastric cancer remains largely unexplored. Here, we found that the expression level of miR-107 was increased in gastric cancer in comparison with the adjacent normal tissues. The enforced expression of miR-107 was able to promote cell proliferation in NCI-N87 and AGS cells, while miR-107 antisense oligonucleotides (antisense miR-107) blocked cell proliferation. At the molecular level, our results further revealed that expression of FOXO1 was negatively regulated by miR-107. Therefore, the data reported here demonstrate that miR-107 is an important regulator in gastric cancer, which will contribute to a better understanding of the important mis-regulated miRNAs in gastric cancer.FEBS letters 12/2013; · 3.54 Impact Factor