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The authors' previous study demonstrated that miR‑128 may exert an inhibitory effect on the osteogenic differentiation of bone marrow‑derived mesenchymal stem cells (BM‑MSCs), but its downstream mechanisms remain to be elucidated. The aim of the present study was to investigate the microRNA (miRNA/miR) and mRNA profiles of differentiated and undifferentiated BM‑MSCs and explore new downstream targets for miR‑128. The sequencing datasets of GSE107279 (miRNA) and GSE112318 (mRNA) were downloaded from the Gene Expression Omnibus database. The differentially expressed miRNAs (DEMs) and genes (DEGs) were identified using the DESeq2 method. The target genes of DEMs were predicted by the miRwalk 2.0 database. The hub target genes of miR‑128 were screened by constructing the protein‑protein interaction (PPI) network and module analysis. The expression levels of miR‑128 and crucial target genes were validated by reverse transcription‑quantitative (RT‑q) PCR before or after transfection of miR‑128 mimics to BM‑MSCs. The miRNA expression profile analysis identified miR‑128 as one of the significantly downregulated DEMs (total 338) in differentiated BM‑MSCs compared with the undifferentiated control. A total of 103 predicted target genes of miR‑128‑3p were overlapped with upregulated DEGs. By calculating the topological properties of each protein in the PPI network, 6 upregulated genes (KIT, NTRK2, YWHAB, GAB1, AXIN1 and RUNX1; fold change was the highest for NTRK2) were considered to be hub genes. Of these, 4 were enriched in module 4 (RUNX1, KIT, GAB1 and AXIN1; RUNX1 was particularly crucial as it can interact with the others), while one was enriched in module 7 (YWHAB). The expression levels of miR‑128 and these 6 target genes during the osteogenic differentiation were experimentally confirmed by RT‑qPCR. In addition, the expression levels of these 6 genes were significantly reversed after transfection of miR‑128‑3p mimics into rat BM‑MSCs compared with the miR‑control group. These findings indicated that miR‑128‑3p may inhibit the osteoblast differentiation of BM‑MSCs by downregulation of these 6 genes, particularly RUNX1, YWHAB and NTRK2.

Aedes mosquitoes can transmit dengue and several other severe vector-borne viral diseases, thereby influencing millions of people worldwide. Insects primarily control and clear the viral infections via their innate immune systems. Mitogen-Activated Protein Kinases (MAPKs) and antimicrobial peptides (AMPs) are both evolutionarily conserved components of the innate immune systems. In this study, we investigated the role of MAPKs in Aedes mosquitoes following DENV infection by using genetic and pharmacological approaches. We demonstrated that knockdown of ERK, but not of JNK or p38, significantly enhances the viral replication in Aedes mosquito cells. The Ras/ERK signaling is activated in both the cells and midguts of Aedes mosquitoes following DENV infection, and thus plays a role in restricting the viral infection, as both genetic and pharmacological activation of the Ras/ERK pathway significantly decreases the viral titers. In contrast, inhibition of the Ras/ERK pathway enhances DENV infection. In addition, we identified a signaling crosstalk between the Ras/ERK pathway and DENV-induced AMPs in which defensin C participates in restricting DENV infection in Aedes mosquitoes. Our results reveal that the Ras/ERK signaling pathway couples AMPs to mediate the resistance of Aedes mosquitoes to DENV infection, which provides a new insight into understanding the crosstalk between MAPKs and AMPs in the innate immunity of mosquito vectors during the viral infection., Author summary Aedes mosquitoes are the vectors that can transmit dengue fever and several other severe vector-borne viral diseases in the human population. Insects control and clear viral infections via their innate immune systems. Studies of the genes and molecules in mosquitos that control pathogen infection may provide insights into finding novel targets for controlling the transmission of mosquito-borne diseases. In this study, we used genetic and pharmacological approaches to investigate the role of MAPKs in Aedes mosquitoes following DENV2 infection in vitro and in vivo. Activation of the Ras/ERK pathway via insulin treatment and overexpression of Ras significantly decreased the DENV titers, whereas inhibition of the Ras/ERK pathway by either U0126 treatment or by Ras knockdown enhanced DENV infection. We demonstrated that the Ras/ERK signaling couples AMPs to mediate the resistance of Aedes mosquitoes to DENV infection, which reveals a novel antiviral mechanism regulated by multiple innate immune components in mosquitoes.

Gastric cancer is a leading cause of cancer worldwide. Our previous studies showed that aberrant activation of JAK/STAT3 signaling confer epigenetically silences STAT3 target genes in gastric cancer. To further investigate the clinical significance of this phenomenon, we performed Illumina 850K methylation microarray analysis in AGS gastric cancer cells, and cells depleted of STAT3. Integrative computational analysis identified SPG20 as a putative STAT3 epigenetic target, showing promoter hypomethylation in STAT3-depleted AGS cells. Bisulphite pyrosequencing and qRT-PCR confirmed that SPG20 is epigenetically silenced by promoter hypermethylation in a panel of gastric cancer cell lines including AGS cells, but not in immortalized gastric epithelial GES cells. Expression of SPG20 could be restored by the treatment with a DNMT inhibitor, further suggesting that SPG20 is epigenetically silenced by promoter methylation. Clinically, a progressive increase in SPG20 methylation was observed in tissues samples from gastritis (n = 34), to intestinal metaplasia (IM, n = 33), to gastric cancer (n = 53). Importantly, SPG20 methylation could be detected in cell-free DNA isolated from serum samples of gastritis, IM and gastric cancer patients, having a progressive similar to tissues. Taken together, SPG20, a potential STAT3 target, is frequently methylated in gastric cancer, representing a novel noninvasive biomarker for early detection of this deadly disease.

Regional metastasis is an important prognostic factor for patients with head and neck squamous cell carcinoma (HNSCC). Neuromedin U (Nmu) is a secreted neuropeptide, named due to its potent uterine contraction‑inducing activity. The aim of the present study was to analyze the significance of Nmu in the regional metastasis of HNSCC. The characteristics of 240 patients recruited from the Department of Otolaryngology Head and Neck Surgery, Renmin Hospital of Wuhan University (Wuhan, China) were summarized retrospectively. The positive rate of neck dissection was analyzed according to the material. The expression levels of Nmu in human tumor samples were analyzed using immunohistochemistry. Subsequently, the expression of Nmu was investigated using a tissue microassay to analyze the association between Nmu protein expression and Tumor Node Metastasis (TNM) status. The positive rate of neck dissection was 51.4% in the study sample. The expression levels of Nmu in primary tumors with regional metastasis were higher, compared with those without metastasis. There was increased protein expression of Nmu in the advanced tumor tissues. The data obtained in the present study demonstrated that the expression of Nmu was correlated with regional metastasis and TNM status. Overexpression of Nmu may be involved in the process of regional metastasis of HNSCC, and may serve as a novel and valuable biomarker for predicting regional metastasis in patients with HNSCC.

We hypothesized that bmo-miR-275 has a potential regulatory function regarding the expression of sericin gene 2 (BmSer-2). First, we examined the expression of bmo-miR-275 and its target gene BmSer-2 in seven different tissues from 5th instar day-3 silkworm larvae. The results showed that they were both specifically expressed in the middle silk gland, implying that spatio-temporal conditions are required for bmo-miR-275 to regulate the expression of BmSer-2. To test this hypothesis, we constructed a pri-bmo-miR-275 expressing plasmid pcDNA3.0 [ie1-egfp-pri-bmo-miR-275-SV40] and BmSer-2-3´UTR recombinant reporter plasmids pGL3.0 [A3-luc-Ser-2-3′ UTR-SV40]. Finally, BmN cells were harvested and luciferase activity was detected. Results showed that luciferase activity was reduced significantly (P

The potential prognostic value of GATA binding protein 3 (GATA3) in breast cancer has recently increased, although the evidence is inconclusive. This meta-analysis of 10 articles involving 5,080 breast cancer patients explored the prognostic and clinicopathological value of GATA3 in breast cancer. Time to tumor progression (TTP) and overall survival (OS) were primary endpoints. Pooled hazard ratio (HR), pooled risk ratio (RR), and 95% confidence interval (CI) were calculated to evaluate the association between GATA3, prognosis, and clinicopathological parameters. High GATA3 expression predicts breast cancer, with a HR (HR = 0.671; 95% CI = 0.475-0.947; P = 0.023) of TTP, but is not associated with OS (HR = 0.889; 95% CI = 0.789-1.001; P = 0.052). GATA3 overexpression is associated with positive ER (RR = 3.155; 95% CI = 1.680-5.923; P = 0.000), positive PR (RR = 3.949; 95% CI = 1.567-9.954, P = 0.004), lower nuclear grade (RR = 0.435; 95% CI = 0.369-0.514; P = 0.000), and smaller tumor size (RR = 0.816; 95% CI = 0.709-0.940; P = 0.005). High GATA3 expression may predict TTP in breast cancer, and such patients may show better clinicopathological features.

Tanshinone IIA, one of the most pharmacologically bioactive phytochemicals isolated from Salvia miltiorrhiza Bunge, possesses several biological activities such as anti-inflammation, anti-cancer, neuroprotection and hypolipidemic activities. In this study, we aim to investigate the hypocholesterolemic effect of tanshinone IIA in hepatic cells. We demonstrated that tanshinone IIA significantly increased the amount of low-density lipoprotein receptor (LDLR) and LDL uptake activity in HepG2 cells at the post-transcriptional regulation. We further demonstrated that tanshinone IIA inhibited the expression of proprotein convertase subtilisin/kexin type 9 (PCSK9) mRNA and mature protein, which may lead to an increase the cell-surface LDLR in hepatic cells. We further identified a regulatory DNA element involved in the tanshinone IIA-mediated PCSK9 down-regulation, which is located between the -411 and -336 positions of the PCSK9 promoter. Moreover, we found that tanshinone IIA markedly increased the nuclear forkhead box O3a (FoxO3a) level, enhanced FoxO3a/PCSK9 promoter complexes formation and decreased the PCSK9 promoter binding capacity of hepatocyte nuclear factor 1α (HNF-1α), resulting in suppression of PCSK9 gene expression. Finally, we found that the statin-induced PCSK9 overexpression was attenuated and the LDLR activity was elevated in a synergic manner by combination of tanshinone IIA treatment in HepG2 cells. Overall, our results reveal that the tanshinone IIA modulates LDLR level and activity via down-regulation of PCSK9 expression in hepatic cells. Our current findings provide a molecular basis of tanshinone IIA to develop PCSK9 inhibitors for cholesterol management.