Long Intergenic Non-Protein Coding RNA 1089 Suppresses Cell Proliferation and Metastasis in Gastric Cancer by Regulating miRNA-27a-3p/Epithelial-Mesenchymal Transition (EMT) Axis

Role of non-coding RNAs as new therapeutic targets in regulating the EMT and apoptosis in metastatic gastric and colorectal cancers

Colorectal cancer (CRC) and gastric cancer (GC), are the two most common cancers of the gastrointestinal tract, and are serious health concerns worldwide. The discovery of more effective biomarkers for early diagnosis, and improved patient prognosis is important. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), can regulate cellular processes such as apoptosis and the epithelial-mesenchymal transition (EMT) leading to progression and resistance of GC and CRC tumors. Moreover these pathways (apoptosis and EMT) may serve as therapeutic targets, to prevent metastasis, and to overcome drug resistance. A subgroup of ncRNAs is common to both GC and CRC tumors, suggesting that they might be used as biomarkers or therapeutic targets. In this review, we highlight some ncRNAs that can regulate EMT and apoptosis as two opposite mechanisms in cancer progression and metastasis in GC and CRC. A better understanding of the biological role of ncRNAs could open up new avenues for the development of personalized treatment plans for GC and CRC patients.

MicroRNA profiles in five pairs of early gastric cancer tissues and adjacent non-cancerous tissues

Approximately half of the world's gastric cancer cases and deaths occur in China. In addition, the incidence and mortality rates of gastric cancer in Gansu province in China are much higher than the average nationwide levels. The present study investigated microRNA (miRNA/miR) profiles in early gastric cancer (EGC) without specific symptoms. miRNA expression levels in five pairs of EGC tissues and adjacent non-cancerous mucosa tissues of patients from Gansu province in China were analyzed using a miRNA microarray. A total of 47 differentially expressed miRNAs (DEMs) were identified. Subsequently, mRNA expression profiles of three pairs of cancer tissues and adjacent non-cancerous tissues from 3 Asian patients with stage I or stage II gastric cancer (stage I/II; American Joint Committee on Cancer classification, Eighth Edition) were obtained from The Cancer Genome Atlas database, and differentially expressed genes (DEGs) were identified. The target genes of DEMs were filtered from the DEGs using the miRDB database and a miRNA-gene network was constructed. The functions of DEMs were evaluated using the tool for annotations of human miRNAs database, and via Gene Ontology analysis, Kyoto Encyclopedia of Genes and Genomes analysis and Gene Set Enrichment Analysis of the target genes. Finally, survival analyses of DEMs, which were in the miRNA-gene network, was performed. The results suggested that a number of miRNAs, including hsa-let-7a-5p, hsa-miR-27a-3p, hsa-miR-126-5p and hsa-miR-424-5p, may serve critical roles in EGC. The present study could provide a basis for the identification of EGC screening biomarkers. Furthermore, the present study may provide a basis for the exploration of the cause of the high incidence of gastric cancer in Gansu province from the perspective of miRNAs.

LncRNA-LINC01089 inhibits lung adenocarcinoma cell proliferation and promotes apoptosis via sponging miR-543

LINC01089, a newly discovered long non-coding RNA (lncRNA), has been reported to inhibit the progression of various types of cancers. This study aimed to characterize LINC01089 in the pathogenesis of lung adenocarcinoma (LUAD). LINC01089 expression in LUAD tissues or/and cells and its association with the overall survival of LUAD patients was analyzed in The Cancer Genome Atlas (TCGA)-LUAD database, by qRT-PCR or by Kaplan-Meier's curve. Databases of StarBase, LncBase, and DEmiRNA were used to predict and confirm the interaction between LINC01089 and potential LINC01089-targeted microRNAs (miRNAs). The expressions of these miRNAs in LUAD tissues or/and cells were determined by qRT-PCR, and dual-luciferase reporter assay was performed to validate lncRNA-miRNA interaction. The expressions of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax) and Cleaved caspase-3 in LUAD cells were analyzed by Western blot. LINC01089 improved overall survival of LUAD patients and was low-expressed in LUAD. Upregulating LINC01089 expression reduced LUAD cell viability, inhibited colony formation, enhanced apoptosis, accompanied by downregulated Bcl-2 and miR-543 and upregulated Bax and Cleaved caspase-3. MiR-543 was determined as a target gene of LINC01089, and was high-expressed in LUAD tissues. Upregulating miR-543 expression induced the opposite effects to LINC01089 upregulation on these cellular biological behaviors and the expressions of Bcl-2, Bax and Cleaved caspase-3. Moreover, the effects of miR-543 upregulation and LINC01089 upregulation were mutually counteracted by each other. LINC01089 inhibited lung adenocarcinoma cell proliferation and promoted apoptosis via sponging miR-543.

Effective Prediction of Prostate Cancer Recurrence through the IQGAP1 Network

IQGAP1 expression was analyzed in: (1) primary prostate cancer, (2) xenografts produced from LNCaP, DU145, and PC3 cells, 3) tumor of PTEN-/- and TRAMP mice, and (3) castration resistant PC (CRPC) produced by LNCaP xenografts and PTEN-/- mice. IQGAP1 downregulations occurred in CRPC and advanced PCs. The downregulations were associated with rapid PC recurrence in the TCGA PanCancer (n = 492, p = 0.01) and MSKCC (n = 140, p = 4 × 10-6) cohorts. Differentially expressed genes (n = 598) relative to IQGAP1 downregulation were identified with enrichment in chemotaxis, cytokine signaling, and others along with reductions in immune responses. A novel 27-gene signature (Sig27gene) was constructed from these DEGs through random division of the TCGA cohort into a Training and Testing population. The panel was validated using an independent MSKCC cohort. Sig27gene robustly predicts PC recurrence at (hazard ratio) HR 2.72 and p < 2 × 10-16 in two independent PC cohorts. The prediction remains significant after adjusting for multiple clinical features. The novel and robust nature of Sig27gene underlie its great translational potential as a prognostic biomarker to predict PC relapse risk in patients with primary PC.