Amniotic fluid (AF) continuously exchanges molecules with the fetus, playing critical roles in fetal development especially via its complex components. Among these components, microRNAs are thought to be transferred between cells loaded in microvesicles. However, the functions of AF microRNAs remain unknown. To date, few studies have examined microRNAs in amniotic fluid. In this study, we employed miRCURY Locked Nucleotide Acid arrays to profile the dynamic expression of microRNAs in AF from mice on embryonic days E13, E15, and E17. At these times, 233 microRNAs were differentially expressed (p< 0.01), accounting for 23% of the total Mus musculus microRNAs. These differentially-expressed microRNAs were divided into two distinct groups based on their expression patterns. Gene ontology analysis showed that the intersectional target genes of these differentially-expressed microRNAs were mainly distributed in synapse, synaptosome, cell projection, and cytoskeleton. Pathway analysis revealed that the target genes of the two groups of microRNAs were synergistically enriched in axon guidance, focal adhesion, and MAPK signaling pathways. MicroRNA-mRNA network analysis and gene- mapping showed that these microRNAs synergistically regulated cell motility, cell proliferation and differentiation, and especially the axon guidance process. Cancer pathways associated with growth and proliferation were also enriched in AF. Taken together, the results of this study are the first to show the functions of microRNAs in AF during fetal development, providing novel insights into interpreting the roles of AF microRNAs in fetal development.

Transglutaminase 2 (TGM2) is a Ca²⁺‑dependent enzyme that is closely associated with cancer progression; however, the function of TGM2 in T‑cell lymphoma remains unclear. In the present study, TGM2 was identified as an upregulated gene by bioinformatics analysis of the microarray datasets GSE132550 and GSE143382 from the Gene Expression Omnibus database. The effects and mechanisms of TGM2 on T‑cell lymphoma cells were evaluated using the Cell Counting Kit‑8, colony formation assay, 5‑ethynyl‑2'‑deoxyuridine (EdU) assay, flow cytometry, reverse transcription‑quantitative polymerase chain reaction, western blotting and gene set enrichment analysis (GSEA). TGM2 expression was shown to be elevated in formalin‑fixed paraffin‑embedded skin biopsies from patients with T‑cell lymphoma relative to skin tissue from healthy cases. TGM2 expression was also increased in T‑cell lymphoma cell lines compared with that in CD4⁺ T cells. Transfection with TGM2 small interfering RNAs (siRNAs) decreased the number of EdU‑positive cells, and the viability and colony formation of T‑cell lymphoma cells. Furthermore, TGM2 siRNAs enhanced the apoptosis of T‑cell lymphoma cells potentially via cleavage of caspase‑3 and poly ADP‑ribose polymerase. GSEA identified the IL‑6/JAK/STAT3 pathway as a potential downstream signalling pathway of TGM2. Notably, the effects of TGM2 siRNAs on T‑cell lymphoma cells were attenuated by IL‑6 and accelerated by IL‑6/JAK/STAT3 inhibitor AG490. These findings indicated that TGM2 siRNAs inhibited the proliferation of T‑cell lymphoma cells by regulating the IL‑6/JAK/STAT3 signalling pathway; therefore, TGM2 may function as a potential therapeutic target for T‑cell lymphoma.

Adult neurogenesis is considered to contribute to a certain degree of plasticity for the brain. However, the effects of adult-born neurons on the brain are still largely unknown. Here, we specifically altered the expression of miR-30c in the subventricular zone (SVZ) and dentate gyrus (DG) by stereotaxic injection with their respective up-and down-regulated lentiviruses. Results showed an increased level of miR-30c enhanced adult neurogenesis by prompting cell-cycles of stem cells, whereas down-regulated miR-30c led to the opposite results. When these effects of miR-30c lasted for three months, we detected significant morphological changes in the olfactory bulb (OB) and lineage alteration in the hippocampus. Tests of olfactory sensitivity and associative and spatial memory showed that a certain amount of adult-born neurons are essential for the normal functions of the OB and hippocampus, but there also exist redundant newborn neurons that do not further improve the functioning of these areas. Our study revealed the interactions between miRNA, adult neurogenesis, brain morphology and function, and this provides a novel insight into understanding the role of newborn neurons in the adult brain.