microRNA-501-5p promotes cell proliferation and migration in gastric cancer by downregulating LPAR1

In spite of the achievement in treatment, the gastric cancer (GC) mortality still remains high. MicroRNAs (miRNAs) are a group of small noncoding RNAs that play a crucial part in tumor progression. In this study, we explored the expression and function of microRNA-501-5p (miR-501-5p) in GC cell lines. Quantitative real-time polymerase chain reaction assay results suggested that miR-501-5p was significantly upregulated in GC tissues and cell lines. And, the Cell Counting Kit-8 colony formation and cell migration assay results showed that the downregulation of miR-501-5p decreased GC cell proliferation and migration. Besides that, we found that GC cell cycle was arrested in G2 phase and cell apoptosis rate was increased by silencing the expression of miR-501-5p in GC cell lines using the flow cytometry. We also found that miR-501-5p could directly target lysophosphatidic acid receptor 1 (LPAR1) and negatively regulate LPAR1 expression in GC cell lines by performing dual-luciferase reporter gene assay and Western blot analysis. And, LPAR1 was significantly downregulated in GC tissues and inversely correlated with miR-501-5p expression. Furthermore, LPAR1 downregulation promoted cell proliferation and migration, which were attenuated by cotransfection of miR-501-5p inhibitor in GC cells. In conclusion, miR-501-5p can promote GC cell proliferation and migration by targeting and downregulating LPAR1. miR-501-5p/LPAR1 may become a potential therapeutic target for GC treatment.     

The Downregulation of Truncated TrkB Receptors Modulated by MicroRNA-185 Activates Full-Length TrkB Signaling and Suppresses the Epileptiform Discharges in Cultured Hippocampal Neurons

Neurochemical Research - Epilepsy is a common neurological disorder characterised by occurrence of spontaneous recurrent epileptiform discharges (SREDs) in neurons. The cellular mechanisms that...     

Identification of microenvironment-related genes with prognostic value in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most common type of kidney tumor. Previous studies have shown that the interaction between tumor cells and microenvironment has an important impact on prognosis. Immune and stromal cells are two vital components of the tumor microenvironment. Our study aimed to better understand and explore the genes involved in immune/stromal cells on prognosis. We used the Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data algorithm to calculate immune/stromal scores. According to the scores, we divided ccRCC patients from The Cancer Genome Atlas database into low and high groups and identified the genes which were differentially expressed and significantly associated with prognosis. The result of functional enrichment analysis and protein-protein interaction networks indicated that these genes mainly were involved in extracellular matrix and regulation of cellular activities. Then another independent cohort from the International Cancer Genome Consortium database was used to validate these genes. Finally, we acquired a list of microenvironment-related genes that can predict prognosis for ccRCC patients.     

Toll-like receptor 4 contributes to uterine activation by upregulating pro-inflammatory cytokine and CAP expression via the NF-κB/P38MAPK signaling pathway during pregnancy

Evidence indicates that inflammatory response is significant during the physiological process of human parturition; however, the specific signaling pathway that triggers inflammation is undefined. Toll-like receptors (TLRs) are key upstream gatekeepers that control inflammatory activation before preterm delivery. Our previous study showed that TLR4 expression was significantly increased in human pregnancy tissue during preterm and term labor. Therefore, we explore whether TLR4 plays a role in term labor by initiating inflammatory responses, therefore promoting uterine activation. The results showed that expression of TLR4, interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α), CC chemokine ligand 2 (CCL-2), and uterine contraction-associated proteins (CAPs) was upregulated in the human and mice term labor (TL) group compared with the not-in-labor (TNL) group, and the TLR4 level positively correlated with CAP expression. In pregnant TLR4-knockout (TLR4^−/−) mice, gestation length was extended by 8 hr compared with the wild-type group, and the expression of IL-1β, IL-6, TNF-α, CCL-2, and CAPs was decreased in TLR4^−/− mice. Furthermore, nuclear factor-κB (NF-κB) and P38MAPK activation is involved in the initiation of labor but was inhibited in TLR4^−/− mice. In uterine smooth muscle cells, the expression of inflammatory cytokines and CAPs decreased when the NF-κB and P38MAPK pathway was inhibited. Our data suggest that TLR4 is a key factor in regulating the inflammatory response that drives uterine activation and delivery initiation via activating the NF-κB/P38MAPK pathway.     

Characterization of Basal and Morphine-Induced Uridine Release in the Striatum: An In Vivo Microdialysis Study in Mice

Uridine, a pyrimidine nucleoside, has been proposed to be a potential signaling molecule in the central nervous system. The understanding of uridine release in the brain is therefore of fundamental importance. The present study was performed to determine the characteristics of basal and morphine-induced uridine release in the striatum of freely moving mice by using the microdialysis technique. To ascertain whether extracellular uridine was derived from neuronal release, the following criteria were applied: sensitivity to (a) K⁺ depolarization, (b) Na⁺ channel blockade and (c) removal of extracellular Ca²⁺. Uridine levels were not greatly affected by infusion of tetrodotoxin (TTX) and were unaffected by either Ca²⁺-free medium or in the presence of EGTA (a calcium chelator), suggesting that basal extracellular uridine levels were maintained mainly by non-vesicular release mechanisms. In addition, both systemic and local application of morphine increased striatal uridine release. The morphine-induced release was reversed by naloxone pretreatment, but was unaffected by TTX or EGTA infusion. Moreover, co-administration of morphine and nitrobenzylthioinosine (NBTI, an inhibitor of nucleotide transporter) produced increases of uridine levels similar to that produced by NBTI or morphine alone, suggesting a nucleotide transporter mechanism involved. Taken together, these findings suggest that morphine produces a μ-opioid receptor-mediated uridine release via nucleoside transporters in a TTX- and calcium-independent manner.     

cDNA cloning,expression, and enzymatic activity of a novel endogenous cellulase from the beetle Batocera horsfieldi

In this study, we report a novel cellulase [β-1,4-endoglucanase (EGase), EC 3.2.1.4] cDNA (Bh-EGase II) belonging to the glycoside hydrolase family (GHF) 45 from the beetle Batocera horsfieldi. The Bh-EGase II gene spans 720 bp and consists of a single exon coding for 239 amino acid residues. Bh-EGase II showed 93.72% protein sequence identity to Ag-EGase II from the beetle Apriona germari. The GHF 45 catalytic site is conserved in Bh-EGase II. Bh-EGase II has three putative N-glycosylation sites at 56–58 (N–K–S), 99–101 (N–S–T), and 237–239 (N–Y–S), respectively. The cDNA encoding Bh-EGase II was expressed in baculovirus-infected insect BmN cells and Bombyx mori larvae. Recombinant Bh-EGase II from BmN cells and larval hemolymph had an enzymatic activity of approximately 928 U/mg. The enzymatic catalysis of recombinant Bh-EGase II showed the highest activity at 50 °C and pH 6.0.     

The Expression and Release of Hsp60 in 6-OHDA Induced In Vivo and In Vitro Models of Parkinson’s Disease

In Parkinson’s disease, dopaminergic neuron damage/death causes the release of soluble substances that are selectively toxic to neighboring/additional dopaminergic neurons through the activation of microglia. Hsp60 can be released from injured cells of central nervous system to activate microglia. However, its expression and role in Parkinson’s disease has not been well understood. Here, we performed a 6-OHDA treated Parkinson’s disease model in adult rats. Western blot analysis showed a time-course expression of Hsp60, which decreased gradually and then rose back. Immunofluorescence staining showed that Hsp60 was decreased in dopaminergic neuron, and most Hsp60 located on the surface of activated microglia. Furthermore, in cellular Parkinson’s disease model, Hsp60 was obviously detected in the culture supernatants after 6-OHDA treatment, and a concomitant decrease in cell extracts. Taken together, our results suggested that Hsp60 could be released extracellularly to activate microglia in Parkinson’s disease model.