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The bicistronic microRNA (miRNA) locus miR-144/451 is highly expressed during erythrocyte development, although its physiological roles are poorly understood. We show that miR-144/451 ablation in mice causes mild erythrocyte instability and increased susceptibility to damage after exposure to oxidant drugs. This phenotype is deeply conserved, as miR-451 depletion synergizes with oxidant stress to cause profound anemia in zebrafish embryos. At least some protective activities of miR-451 stem from its ability to directly suppress production of 14-3-3ζ phospho-serine/threonine-binding protein that inhibits nuclear accumulation of transcription factor FoxO3, a positive regulator of erythroid anti-oxidant genes. Thus, in miR-144/451^/^ erythroblasts, 14-3-3ζ accumulates, causing partial relocalization of FoxO3 from nucleus to cytoplasm with dampening of its transcriptional program, including anti-oxidant-encoding genes Cat and Gpx1. Supporting this mechanism, overexpression of 14-3-3ζ in erythroid cells and fibroblasts inhibits nuclear localization and activity of FoxO3. Moreover, shRNA suppression of 14-3-3ζ protects miR-144/451^/^ erythrocytes against peroxide-induced destruction, and restores catalase activity. Our findings define a novel miRNA-regulated pathway that protects erythrocytes against oxidant stress, and, more generally, illustrate how a miRNA can influence gene expression by altering the activity of a key transcription factor. [ABSTRACT FROM AUTHOR]

The cell migration capability of A549 and SK-MES-1 cells was determined using a cell scratch test. (C) Representative images and (D) statistical analysis are presented. [Corrigedum] miR-185 inhibits non-small cell lung cancer cell proliferation and invasion through targeting of SOX9 and regulation of Wnt signaling A549 and SK-MES-1 cells were transfected with miR-185 mimics or miR-185 inhibitor to achieve ectopic miR-185 expression or miR-185 inhibition. [Extracted from the article]

SRY-box 9 (SOX9) is an important transcription factor required for development, which has additionally been reported to be an independent prognostic indicator for the survival of patients with non-small cell lung cancer (NSCLC). Accumulating evidence has indicated that dysregulation of microRNAs (miRNAs/miRs) may contribute to the initiation and progression of cancer. SOX9 may be regulated by a number of miRNAs in different types of cancer, including in NSCLC. The present study sought to identify novel candidate miRNAs associated with SOX9 in NSCLC using online tools, and investigated the detailed functions of miR-185, which suppressed SOX9 mRNA expression most strongly out of the candidate miRNAs. It was observed that ectopic miR-185 expression significantly suppressed NSCLC cell proliferation, invasion and migration. Using luciferase reporter gene and RNA immunoprecipitation assays, SOX9 was confirmed to be a direct target of miR-185. In addition, the downstream Wnt signaling-associated factors β-catenin and c-Myc proto-oncogene protein (Myc) were demonstrated to be inhibited by miR-185 overexpression. SOX9, β-catenin and c-Myc mRNA expression was significantly upregulated in NSCLC tissues, and was inversely correlated with miR-185 expression. The results of the present study demonstrated that rescuing miR-185 expression in NSCLC, thereby inhibiting SOX9 expression and the downstream Wnt signaling, and leading to the suppression of NSCLC cell proliferation, invasion and migration, may be a promising strategy for the treatment of NSCLC. [ABSTRACT FROM AUTHOR]