Effects of BCL2 transfection on the cell cycle and proliferation of human GES-1 cells.

We investigated the effects of BCL2 transfection on the cell cycle and proliferation of GES-1 cells. A pcDNA3-BCL2 plasmid was used to transfect GES-1 cell line human gastric epithelial cells. Clones were obtained by G418 screening. BCL2-positive cells were identified by fluorescence immunohistochemistry. The pcDNA3-BCL2 vectors carrying the NeoR gene were transfected into GES-1 cells, while the empty plasmid was transfected into the same cells as controls. BCL2-positive clones were screened by neomycin 418 (G418). Flow cytometry was used to detect the cell cycle. Hematoxylin and eosin (H&E) staining revealed morphological changes, and the effects of BCL2 transfection on cell proliferation were analyzed by cell counting and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The plasmid pcDNA3-BCL2 was identified by restriction enzyme digestion. Different degrees of BCL2 gene expression were detected in all seven clones. BCL2 was expressed mainly in the cytoplasm and the nuclear membrane. There were significantly more S-phase cells in the transfection group than in the controls. The morphology did not change after H&E staining. Cell growth was faster than in the controls after transfection for 6 days. At 24, 48, and 72 h after transfection, the A values were 4.15 ± 0.31, 5.98 ± 0.56, and 8.94 ± 0.79; those of the controls were 3.01 ± 0.20, 4.76 ± 0.52, and 7.69 ± 0.84; there was a significant difference between the two groups (P < 0.05). BCL2 transfection increased GES-1 cells in the S phase; the GES-1 cells were stable and BCL2 expression was high, which promoted cell proliferation.

Integrated miRNA-mRNA analysis of Epstein-Barr virus-positive nasopharyngeal carcinoma.

This study aims to identify the crucial miRNAs in Epstein-Barr virus-positive nasopharyngeal carcinoma (NPC) and their target genes. Gene expression profile data (GSE12452) that included 31 NPC and 10 normal nasopharyngeal tissue specimens were downloaded. Differentially expressed genes (DEGs) were identified using significance analysis of microarrays. The underlying function of DEGs was predicted via Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses. The miRNA sequencing dataset GSE14738 was also downloaded, and expression levels of miRNA were calculated by the number of reads mapped to each miRNA. The selected miRNAs were integrated into the miRecords database to obtain their target genes. Target genes associated with DEGs were used to construct the interaction network via Cytoscape. A total of 1437 DEGs between NPC and control were identified, most of which were enriched in cell cycle and extracellular matrix-receptor interaction signaling pathways. Furthermore, 112 miRNAs were considered upregulated in NPC samples. A total of 2228 relationships between 39 miRNAs and 1247 target genes were obtained, of which 182 relationships between 32 miRNAs and 97 target genes were chosen to construct an interaction network. The interactions between DEGs and the let-7 or miR-29 families appeared strongest in this network, where CDC25A, COL3A1, and COL1A1 were regulated by several let-7 family members, while COL4A1 and COL5A2 were regulated by several miR-29 family members. The let-7 and miR-29 families may be related to the development of NPC by regulating the genes involved in cell cycle and ECM-receptor interaction.