MicroRNA-21 (miR-21) is considered to play a key role in many cellular processes, affecting tumorigenesis by inhibiting target gene expression. However, its role in diffuse large B-cell lymphoma (DLBCL) is still unclear, and there are no in depth studies on relationship between miR-21 and cellular phenotype. This study was aimed to investigated the expression and role of miR-21 in the regulation of cell biological behavior in DLBCL. The expressions of miR-21 in three DLBCL cell lines were detected by real-time quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The possible roles of miR-21 in the biological and behavioral properties of DLBCL were explored by transfection of anti-miR-21 for miR-21 knockdown. In addition, PDCD4 and PTEN were assessed by luciferase reporter assay, qRT-PCR and Western blot. The results revealed that miR-21 expression was significantly upregulated in activated B-cell-like DLBCL cells as compared to germinal centre-like DLBCL cells. The inhibition of miR-21 could induce suppression of proliferation and invasion, as well as increase apoptosis in DLBCL. Moreover, knockdown of miR-21 increased the expressions of PDCD4 and PTEN at the protein level but not at the mRNA level. It is concluded the miR-21 can regulate proliferation, invasion, and apoptosis, so it has a potential therapeutic application in DLBCL.
Apoptosis ; Cell Line, Tumor ; Cell Transformation, Neoplastic ; Gene Expression Regulation, Neoplastic ; Humans ; Lymphoma, Large B-Cell, Diffuse ; genetics ; pathology ; MicroRNAs ; genetics ; PTEN Phosphohydrolase ; Real-Time Polymerase Chain Reaction ; Transfection ; Up-Regulation

Objective: To understand the viral etiology of a clustered case of human infection outbreak in the middle school of Huai’an city. Methods: Nasopharyngeal swab samples from patients were collected and rapidly detected by Real-time RT-PCR and the target virus isolated in cells. Furthermore, HA1 segments of target virus were amplified by RT-PCR and sequenced. The genetic and phylogenetic analysis based on HA1 genes was computed. Results: Influenza A(H1N1)pdm09 viral nucleic acid in 11 nasopharyngeal swab samples from patients in the outbreak were positive. Compared to the vaccine strains A/California/07/2009, the Huai’an isolates, nucleotide identity was 97.7%-98.1%, and amino acid identity was 96.6%-97.4%. Phylogenetic analysis of HA1 segment sequences indicated that the Huai’an strains from the outbreak were related closely to the viruses isolated in the year of 2014. Sequence analysis indicated that the Huai’an isolates had no amino acid substitution in the receptor binding sites and glycosylation sites, while in the Ca1 of antigenic determinant of HA1 the Huai’an isolates had an amino acid substitution of S for T at 220. Conclusions The pathogen of the clustered case of human infection was Influenza A(H1N1)pdm09 virus. Though the Huai’an isolates had one animo acid substitution in the Ca1 of antigenic determinant, the antigenicity characteristic remained unchanged.