Analysis of lncRNA-Associated ceRNA Network Reveals Potential lncRNA Biomarkers in Human Colon Adenocarcinoma.

Long non-coding RNAs (lncRNAs) acting as competing endogenous RNAs (ceRNAs) play significant roles in the development of tumors, but the functions of specific lncRNAs and lncRNA-related ceRNA networks have not been fully elucidated for colon adenocarcinoma (COAD). In this study, we aimed to clarify the lncRNA-microRNA (miRNA)-mRNA ceRNA network and potential lncRNA biomarkers in COAD. We extracted data from The Cancer Genome Atlas (TCGA) and identified COAD-specific mRNAs, miRNAs, and lncRNAs. The biological processes in Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) were analyzed for COAD-specific mRNAs. We then constructed a ceRNA network of COAD-specific mRNAs, miRNAs and lncRNAs and analyzed the correlation between expression patterns and clinical features of the lncRNAs involved. After identifying potential mRNA targets of 4 lncRNAs related to overall survival (OS), we conducted stepwise analysis of these targets through GO and KEGG. Using tissue samples from our own patients, we also verified certain analytical results using quantitative real-time PCR (qRT-PCR). Data from 521 samples (480 tumor tissue and 41 adjacent non-tumor tissue samples) were extracted from TCGA. A total of 258 specific lncRNAs, 206 specific miRNAs, and 1467 specific mRNAs were identified (absolute log2 [fold change] > 2, false discovery rate < 0.01). Analysis of KEGG revealed that specific mRNAs were enriched in cancer-related pathways. The ceRNA network was constructed with 64 lncRNAs, 18 miRNAs, and 42 mRNAs. Among these lncRNAs involved in the network, 3 lncRNAs (LINC00355, HULC, and IGF2-AS) were confirmed to be associated with certain clinical features and 4 lncRNAs (HOTAIR, LINC00355, KCNQ1OT1, and TSSC1-IT1) were found to be negatively linked to OS (log-rank p < 0.05). KEGG showed that the potential mRNA targets of these 4 lncRNAs may be concentrated in the MAPK pathway. Certain results were validated by qRT-PCR. This study providing novel insights into the lncRNA-miRNA-mRNA ceRNA network and reveals potential lncRNA biomarkers in COAD.

Zhang Z ，Qian W ，Wang S ，Ji D ，Wang Q ，Li J ，Peng W ，Gu J ，Hu T ，Ji B ，Zhang Y ，Wang S ，Sun Y ... -  《-》

Integrated analysis of long non-coding RNA‑associated ceRNA network reveals potential lncRNA biomarkers in human lung adenocarcinoma.

Sui J ，Li YH ，Zhang YQ ，Li CY ，Shen X ，Yao WZ ，Peng H ，Hong WW ，Yin LH ，Pu YP ，Liang GY ... -  《-》

A Competing Endogenous RNA Network Reveals Novel Potential lncRNA, miRNA, and mRNA Biomarkers in the Prognosis of Human Colon Adenocarcinoma.

Accumulating evidence indicated that long noncoding RNAs (lncRNAs) have a wide range of biological functions and may play significant roles in tumorigenesis and progression. However, the understanding of its functions and related competitive endogenous RNAs (ceRNAs) networks is much less than that of protein-coding genes, particularly in colon adenocarcinoma. We comprehensively analyzed the sequencing data of protein-coding and noncoding RNAs in colon adenocarcinoma patients from The Cancer Genome Atlas (TCGA) database. Next, we constructed colon adenocarcinoma-specific ceRNA network and evaluated the effect of these RNAs on overall survival (OS) for colon adenocarcinoma patients. Totally, 1138 differentially expressed lncRNAs (DElncRNAs), 245 microRNAs (DEmiRNAs), and 2081 mRNAs (DEmRNAs) were identified using a threshold of |log2FoldChange| >2.0 and adjusted P-value < 0.01. Subsequently, a colon adenocarcinoma-specific ceRNA network was successfully established with133 DElncRNAs, 29 DEmiRNAs, and 55 DEmRNAs. Among ceRNA network, seven DElncRNAs (AL590483.1, AP004609.1, ARHGEF26-AS1, HOX transcript antisense RNA (HOTAIR), ITCH-IT1, KCNQ1OT1, and LINC00491), four DEmiRNAs (hsa-mir-143, hsa-mir-183, hsa-mir-216a, and hsa-mir-424), and six DEmRNAs (FJX1, TPM2, ULBP2, PDCD4, PLAU, and SERPINE1) significantly correlated with OS (all P-value < 0.05). Notably, several interactions were highlighted in the ceRNA network, such as "KCNQ1OT1-hsa-mir-183-PDCD4", "KCNQ1OT1-hsa-mir-424-TPM2", "HOTAIR-hsa-mir-143-SERPINE1", and "ARHGEF26-AS1-hsa-mir-143-SERPINE1". These findings reveal several molecules might be novel important prognostic factors and potential treatment targets for colon adenocarcinoma. In addition, these observations contribute to a more comprehensive understanding of lncRNA-related ceRNA network and provide novel strategies for subsequent functional studies of lncRNAs in colon adenocarcinoma.

Wang WJ ，Li HT ，Yu JP ，Han XP ，Xu ZP ，Li YM ，Jiao ZY ，Liu HB ... -  《-》

Comprehensive Analysis of Differentially Expressed Profiles of lncRNAs/mRNAs and miRNAs with Associated ceRNA Networks in Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) is a subtype of highly malignant breast cancer with poor prognosis. Growing evidence indicates that Long noncoding RNAs (lncRNAs) play important regulatory roles in the development and progression of a variety of cancers including breast cancer. However, the underlying mechanisms remain largely unknown. Here, we compared the expression profiles of mRNAs, lncRNAs and miRNAs between 111 TNBC tissues and 104 non-cancerous tissues utilizing RNA-Seq Data from The Cancer Genome Atlas (TCGA). Gene Ontology and KEGG pathway enrichment analyses were executed to investigate the principal functions of the significantly dysregulated mRNAs. Moreover, Kaplan-Meier survival analyses were performed to determine the effects of differentially expressed lncRNAs/mRNAs/miRNAs on overall survival. Subsequently, we constructed a competing endogenous RNA (ceRNA) network, which included 66 dysregulated lncRNAs, 24 miRNAs and 55 mRNAs. The four dysregulated lncRNAs, three aberrantly expressed miRNAs and four mRNAs were confirmed in the ceRNA network by qRT-PCR in 30 pairs of samples, respectively. A total of 1441 lncRNAs, 114 miRNA and 2501 mRNAs were found to be differentially expressed in TNBC tissues compared with controls. 109 lncRNAs and 124 mRNAs might serve as prognostic signature for patients with TNBC according to the survival analysis. Functional analysis revealed that 19 mRNAs in the ceRNA network were enriched in 17 cancer-related pathways. Taken together, we identified novel lncRNAs/miRNAs which may serve as potential biomarkers to predict the survival and therapeutic targets for TNBC patients based on a large-scale sample. More importantly, we constructed the ceRNA network of TNBC, which provides valuable information to further explore the molecular mechanism underlying tumorigenesis and development of TNBC.

Yang R ，Xing L ，Wang M ，Chi H ，Zhang L ，Chen J ... -  《-》

Integration analysis of long non-coding RNA (lncRNA) role in tumorigenesis of colon adenocarcinoma.

Poursheikhani A ，Abbaszadegan MR ，Nokhandani N ，Kerachian MA ... -  《BMC Medical Genomics》