miR-16 Inhibits Extracellular Signal-Regulated Kinases (ERK) Mitogen-Activated Protein Kinases (MAPK) Signaling to Affect Epithelial-Mesenchymal Transition (EMT) and Invasion of Glioma Cells

Abnormal MEK1 expression is associated with tumor cell EMT, invasion and metastasis. Decreased miR-16 level is associated with glioma. Bioinformatics analysis showed a relationship between miR-16 and MEK1. This study assessed whether miR-16 regulates MEK1 expression and affects glioma cell EMT and invasion. The tumor tissues and adjacent glioma tissues were collected to measure miR-16 and MEK1 mRNA. The dual luciferase assay validated the relation of miR-16 with MEK1. U251 cells were cultured and assigned into NC group and mimic group, followed by analysis of cell biological behaviors, and MEK1, p-ERK1/2, E-cadherin, N-Cadherin expression. Compared with adjacent tissues, miR-16 expression was significantly decreased and MEK1 was elevated in glioma tissues. Compared with HEB, miR-16 in glioma U251 and SHG44 cells was decreased and MEK1 was increased. Dual luciferase reporter gene experiments confirmed the relation of miR-16 with MEK1. Transfection of miR-16 mimic significantly down-regulated MEK1, p-ERK1/2 and N-cadherin in U251 cells, upregulated E-cadherin, inhibited cell proliferation, promoted apoptosis, and attenuated EMT and invasion of glioma cells. In conclusion, decreased miR-16 expression and increased MEK1 expression is related to glioma pathogenesis. Overexpression of miR-16 can inhibit MEK1 expression, ERK/MAPK signaling, glioma cell proliferation, promote apoptosis, and attenuate EMT and invasion.

Platelet-Derived Growth Factor-BB Inhibits Intervertebral Disc Degeneration via Suppressing Pyroptosis and Activating the MAPK Signaling Pathway

Platelet-derived growth factor-BB (PDGF-BB) is a cytokine involved in tissue repair and tumor progression. It has been found to have expression differences between normal and degenerative intervertebral discs. However, it is not clear whether PDGF-BB has a protective effect on intervertebral disc degeneration (IDD). In this experiment, we treated nucleus pulposus cells (NPCs) with IL-1β to simulate an inflammatory environment and found that the extracellular matrix (ECM) anabolic function of NPCs in an inflammatory state was inhibited. Moreover, the induction of IL-1β also enhanced the expression of NLRP3 and the cleavage of caspase-1 and IL-1β, which activated the pyroptosis of NPCs. In this study, we studied the effect of PDGF-BB on IL-1β-treated NPCs and found that PDGF-BB not only significantly promotes the ECM anabolism of NPCs, but also inhibits the occurrence of pyroptosis and the production of pyroptosis products of NPCs. Consistent with this, when we used imatinib to block the PDGF-BB receptor, the above-mentioned protective effect disappeared. In addition, we found that PDGF-BB can also promote the ECM anabolism of NPCs by regulating the ERK, JNK, PI3K/AKT signaling pathways, but not the P38 signaling pathway. In vivo studies, mice that blocked PDGF-BB receptors showed more severe histological manifestations of intervertebral disc degeneration. In summary, our results indicate that PDGF-BB participates in inhibiting the occurrence and development of IDD by inhibiting pyroptosis and regulating the MAPK signaling pathway.

Characteristic Features of the Transcriptome in a Rat Strain with Audiogenic Epilepsy

Audiogenic epilepsy (AE), developing in rodent strains in response to sound, is widely used as the model of generalized convulsive epilepsy, while the molecular mechanisms determining AE are currently poorly understood. The brain region that is crucial for AE development isthe inferior and superior colliculi (IC, SC). We compared IC-SC gene expression profiles in rats with different AE susceptibility using transcriptome analysis.The transcriptomes were obtained from the IC-SC of Wistar rats (with no AE), Krushinsky-Molodkina (KM) strain rats (100% AE susceptible), and ”0” strain rats (with no AE) selected from F2 KM x Wistar hybrids for AE absence. KM gene expression displayed characteristic differences inboth of the strains that were not susceptible to AE. There was increased expression of a number of genes responsible for positive regulation of the MAPK signaling cascade, as well as of genes responsible for the production of interferon and several other cytokines. An increase in the expression levels of theTTR gene was found in KM rats, as well as significantly lower expression of the Msh3 gene (involved in post-replicative DNA repair systems). AE was also describedin the 101/HY mouse strain with a mutation in the locus controlling DNA repair. The DNA repair system defects could be the primary factor leading to the accumulation of mutations, which, in turn, promote AE. Keywords: udiogenic seizure, KM strain, transcriptome, TTR gene, Msh3 gene, DNA repair

An Integrative Analysis of Transcriptomics and Proteomics Reveals Novel Insights into the Response in the Midgut of Spodoptera frugiperda Larvae to Vip3Aa

The insecticidal Vip3 proteins, secreted by Bacillus thuringiensis (Bt) during its vegetative growth phase, are currently used in Bt crops to control insect pests, and are genetically distinct from known insecticidal Cry proteins. Compared with Cry toxins, the mechanisms of Vip3 toxins are still poorly understood. Here, the responses of Spodoptera frugiperda larvae after Vip3Aa challenge are characterized. Using an integrative analysis of transcriptomics and proteomics, we found that Vip3Aa has enormous implications for various pathways. The downregulated genes and proteins were mainly enriched in metabolic pathways, including the insect hormone synthesis pathway, whereas the upregulated genes and proteins were mainly involved in the caspase-mediated apoptosis pathway, along with the MAPK signaling and endocytosis pathways. Moreover, we also identified some important candidate genes involved in apoptosis and MAPKs. The present study shows that exposure of S. frugiperda larvae to Vip3Aa activates apoptosis pathways, leading to cell death. The results will promote our understanding of the host response process to the Vip3Aa, and help us to better understand the mode of action of Vip3A toxins.

Identification and Validation of DEPDC1B as an Independent Early Diagnostic and Prognostic Biomarker in Liver Hepatocellular Carcinoma

Liver hepatocellular carcinoma (LIHC) is one of the most lethal tumors worldwide, and while its detailed mechanism of occurrence remains unclear, an early diagnosis of LIHC could significantly improve the 5-years survival of LIHC patients. It is therefore imperative to explore novel molecular markers for the early diagnosis and to develop efficient therapies for LIHC patients. Currently, DEPDC1B has been reported to participate in the regulation of cell mitosis, transcription, and tumorigenesis. To explore the valuable diagnostic and prognostic markers for LIHC and further elucidate the mechanisms underlying DEPDC1B-related LIHC, numerous databases, such as Oncomine, Gene Expression Profiling Interactive Analysis (GEPIA), UALCAN, Kaplan-Meier plotter, and The Cancer Genome Atlas (TCGA) were employed to determine the association between the expression of DEPDC1B and prognosis in LIHC patients. Generally, the DEPDC1B mRNA level was highly expressed in LIHC tissues, compared with that in normal tissues (p < 0.01). High DEPDC1B expression was associated with poor overall survival (OS) in LIHC patients, especially in stage II, IV, and grade I, II, III patients (all p < 0.05). The univariate and multivariate Cox regression analysis showed that DEPDC1B was an independent risk factor for OS among LIHC patients (HR = 1.3, 95% CI: 1.08–1.6, p = 0.007). In addition, the protein expression of DEPDC1B was validated using Human Protein Atlas database. Furthermore, the expression of DEPDC1B was confirmed by quantitative real-time polymerase chain reaction (qRT-PCR) assay using five pairs of matched LIHC tissues and their adjacent noncancerous tissues. The KEGG pathway analysis indicated that high expression of DEPDC1B may be associated with several signaling pathways, such as MAPK signaling, the regulation of actin cytoskeleton, p53 signaling, and the Wnt signaling pathways. Furthermore, high DEPDC1B expression may be significantly associated with various cancers. Conclusively, DEPDC1B may be an independent risk factor for OS among LIHC cancer patients and may be used as an early diagnostic marker in patients with LIHC.

JAC1 Targets YY1-Mediated JWA/p38 MAPK Signaling to Inhibit Proliferation and Induce Apoptosis in TNBC

Background:Triple negative breast cancer (TNBC)is a type of breast cancer with poor prognosis, and still has no adequate therapeutic target and ideal medicine.The public database and the relative studies have shown that low expression of JWA is closely related to the poor overall survival in many cancers including breast cancer. However, the precise biological functions and behind mechanisms of JWA in TNBC are still unclear.Methods:Both TCGA and GEO databases were used to confirm the relationship between expression levels of JWA and overall survival inTNBC cases.JAC1, an agonisticsmall compound of JWA gene, was used in TNBC modelsin vitro and in vivo. The routine cellular and molecular assays include CCK-8, colony formation, EdUincorporation, the flow cytometry, Western blot, immunohistochemistry,immune-fluorescence microscopy and reporter gene assays were conducted in this study.Results:Low expression of JWA was associated with poor prognosis in TNBC patients. JAC1 treatment inhibited TNBCcells proliferation and promoted apoptosis in vitro and in vivo. JAC1 specifically combined and targeted YY1toeliminate its transcriptional inhibition on JWA gene.At the same time, JAC1promoted ubiquitination and degradation of YY1. The rescued JWA induced G1 phase arrest and apoptosis in TNBC cellsthrough the p38 MAPK signaling pathway. In addition, JAC1 disrupted the interaction between YY1 and HSF1, and suppressed the oncogenic role of HSF1 in TNBC throughp-Aktsignaling pathway.Conclusions:We discovered for the first time that JAC1 is a YY1 targeting compoundand maybe a potential therapeutic agent for TNBC.