RESUMEN
Gastric cancer (GC) is the third leading cause of cancer-associated mortality. In a previous study, we identified that α-enolase (ENO1) promoted cell migration in GC, but the underlying molecular mechanisms remain to be fully elucidated. In the present study, small interfering RNAs were identified to interfere with ENO1 expression. The cDNA expression profiling was performed using an Affymetrix mRNA array platform to identify genes that may be associated with ENO1 in human GC cell line MGC-803. The differentially expressed genes (DEGs) were identified using the reverse transcription-quantitative polymerase chain reaction, followed by a series of bioinformatic analyses. As a result, there were 448 DEGs, among which 183 (40.85%) were downregulated. The most significant functional terms for the DEGs were the nuclear lumen for cell components (P=2.83×10-4), transcription for biological processes (P=3.7×10-7) and transcription factor activity for molecular functions (P=1.16×104). In total, six significant pathways were enriched, including the most common cancer-associated forkhead box O signaling pathway (P=0.0077), microRNAs in cancer (P=0.0183) and the cAMP signaling pathway (P=0.0415). Furthermore, a network analysis identified three hub genes (HUWE1, PPP1CB and HSPA4), which were all involved in tumor metastasis. Taken together, the DEGs, significant pathways and hub genes identified in the present study shed some light on the molecular mechanisms of ENO1 involved in the pathogenesis of GC.
RESUMEN
Our preview studies showed TPI gene which encodes the Triosephosphate isomerase was overexpressed in human gastric cancer (GC) tissues. However, the potential molecular mechanisms how TPI influences the GC development is not clear. Here, we performed global gene expression profiling for TPI knockdown using microarrays in human GC cell line MGC-803 cells. The differentially expressed genes (DEGs) were identified using reverse transcription-quantitative polymerase chain reaction analysis. Then the DEGs were analyzed by an online software WebGestalt to perform the functional analysis, pathway analysis and network analysis. The protein-protein interaction (PPI) networks were visualized by Cytoscape and the module analysis was performed by ClusterONE. As a result, a total of 920 DEGs including 197 up- and 723 down-regulated genes were screened out. The DEGs were found to be significantly associated with the metabolic process, biological regulation, protein binding and ion binding. There were 11 significant pathways were enriched, and one of the most significant pathway was transcriptional misregulation in cancer (P<0.01), which contained common cancer-related genes, such as DUSP6, ETV5, IL6, PLAU, PPARG and HMGA2. Two PPI networks were constructed from BioGRID and TCGA_RNASeq_STAD, respectively. One network presented 25 genes with degree >10, and EGFR was the most "hub gene" with degree of 74. Four significant modules were identified and mainly enriched in protein domain of Histone and G-protein beta WD-40 repeat. Another network had 4 significant modules and they were associated with protein domain of MHC class I-like antigen recognition and Epidermal growth factor receptor ligand. In conclusion, DEGs and hub genes identified in the present study help us understand the molecular mechanisms of TPI in the carcinogenesis and progression of gastric cancer.
Asunto(s)
Redes Reguladoras de Genes/genética , Neoplasias Gástricas/genética , Triosa-Fosfato Isomerasa/genética , Línea Celular Tumoral , Regulación hacia Abajo/genética , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/genética , Técnicas de Silenciamiento del Gen/métodos , Humanos , Mapas de Interacción de Proteínas/genética , Transducción de Señal/genéticaRESUMEN
Triosephosphate isomerase (TPI) is highly expressed in many types of human tumors and is involved in migration and invasion of cancer cells. However, TPI clinicopathological significance and malignant function in gastric cancer (GC) have not been well defined. The present study aimed to examine TPI expression in GC tissue and its biological functions. Furthermore, we investigated its downstream genes by gene chip technology. Our results showed that TPI expression was higher in gastric cancer tissues than adjacent tissues, although no statistical differences were found between TPI expression and clinicopathological factors. TPI overexpression in human gastric carcinoma cell line BGC-823 enhanced cell proliferation, invasion and migration, but did not change cell cycle distribution, while TPI knockdown suppressed proliferation, invasion and migration, induced apoptosis and increased G2/M arrest of human gastric carcinoma cell line MGC-803. Since the cell division cycle associated 5 (CDCA5) was identified as the one with the most decreased expression after TPI knockdown, we investigated its role in MGC-803 cells. The results showed that CDCA5 knockdown also inhibited proliferation, migration, induced apoptosis and increased G2/M arrest similarly to TPI knockdown. CDCA5 overexpression promoted MGC-803 cell proliferation, clone formation and migration abilities. These results indicated that TPI expression level might affect GC cell behavior, suggesting that both TPI and CDCA5 might be considered as potential tumor markers related with GC development and might be potential new targets in GC treatment.
Asunto(s)
Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Triosa-Fosfato Isomerasa/metabolismo , Adulto , Anciano , Apoptosis/genética , Biomarcadores de Tumor/genética , Puntos de Control del Ciclo Celular/genética , División Celular/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Femenino , Puntos de Control de la Fase G2 del Ciclo Celular/genética , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología , Neoplasias Gástricas/patologíaRESUMEN
Triosephosphate isomerase (TPI) is highly expressed in many human cancers and is involved in migration and invasion of cancer cells. However, TPI clinicopathological significance and prognostic value in gastric cancer (GC) are not yet well defined. The aim of the present work was to evaluate TPI expression in GC tissue and its prognostic value in GC patients.TPI expression was analyzed in 92 primary GC tissues and 80 adjacent normal mucosa tissues from GC patients undergoing gastrectomy by immunohistochemical analysis of tissue microarrays (TMAs). Univariate and multivariate analyses were performed to investigate TPI prognostic significance in GC patients.Immunohistochemical staining score showed that TPI expression in cancer tissues was significantly higher than in adjacent normal mucosa (Pâ<â.001). Univariate analysis revealed that TPI expression, depth of invasion, lympho node metastasis, tumor node metastasis (TNM) stage, and tumor diameter were associated with negative prognostic predictors for overall survival in GC patients (Pâ<â.05). High TPI expression represented a significant predictor of shorter survival in GC patients with positive lymphatic metastasis (Pâ=â.022) and tumor diameter >5âcm (Pâ=â.018). Cox multivariate analysis identified TPI expression, TNM stage, and tumor diameter as independent prognostic factors in GC patients.TPI expression might be considered as a novel prognostic factor to evaluate GC patients' survival.
