Effects of polo-like kinase (PLK1) on proliferation, migration and invasion capacities of gastric cancer cells through epithelial-mesenchymal transition (EMT) were investigated. Small-interfering ribonucleic acid (siRNA) with targeted interference in PLK1 gene was designed and transfected into gastric cancer MGC-803 cells via Lipofectamine to inhibit the expression of PLK1 gene in MGC-803 cells. The proliferation of MGC-803 cells was detected via methyl thiazolyl tetrazolium (MTT) assay. The mRNA and protein expression of PLK1 and EMT-related marker (E-cadherin) was detected via real-time polymerase chain reaction and western blot analysis, respectively. The effects of interference in PLK1 gene on migration and invasion of MGC-803 cells were studied via wound healing assay and Transwell chamber assay, respectively. Results of MTT assay showed that compared with that in control group, the cell proliferation in PLK1 siRNA group was significantly inhibited (p<0.01). Compared with those in control group, the mRNA and protein expression of PLK1 in PLK1 siRNA group was significantly decreased (p<0.01), but the mRNA and protein expression of E-cadherin was obviously upregulated (p<0.01). Results of wound healing assay and invasion assay showed that the capacity of migration and invasion of MGC-803 cells in PLK1 siRNA group was significantly inhibited compared with those in control group (p<0.01). In conclusion, PLK1 enhances the proliferation, migration and invasion of gastric cancer MGC-803 cells through affecting EMT.
Deguelin is a naturally occurring rotenoid with marked chemopreventive and antitumor activity. Cisplatin, characterized by damaging DNA, is widely used in the chemotherapy of malignancies, including gastric cancer. The present study investigated whether synergistic effects exist between the combination of deguelin and cisplatin, and the possible mechanism in vitro. The interactive effects of deguelin in combination with various concentrations of cisplatin were evaluated in the human gastric cancer MGC-803 cell line. The inhibition of cell proliferation was determined by 3-(4,5)-dimethylthiazol(-2-yl)-2,5-diphenyltetrazolium bromide assay and the mechanisms underlying the effects were further evaluated by western blot analysis. The results revealed that the combined treatment of deguelin and cisplatin exhibited a marked inhibition of MGC-803 cell proliferation when compared with that of the single therapies in vitro. In addition, isobologram analysis revealed that this combined treatment showed a synergistic effect. These observations may have promising therapeutic value for gastric cancer and thus warrant further investigation.
Objectives
Available literature documents that ischemic stroke can disrupt the morphology and function of mitochondria and that the latter in other disease models can be preserved by neuropilin-1 (NRP-1) via oxidative stress suppression. However, whether NRP-1 can repair mitochondrial structure and promote functional recovery after cerebral ischemia is still unknown. This study tackled this very issue and explored the underlying mechanism.
Methods
Adeno-associated viral (AAV)-NRP-1 was stereotaxically inoculated into the cortex and ipsilateral striatum posterior of adult male Sprague-Dawley (SD) rats before a 90-min transient middle cerebral artery occlusion (tMCAO) and subsequent reperfusion. Lentivirus (LV)-NRP-1 was transfected into rat primary cortical neuronal cultures before a 2-h oxygen-glucose deprivation and reoxygenation (OGD/R) injury to neurons. The expression and function of NRP-1 and its specific protective mechanism were investigated by Western Blot, immunofluorescence staining, flow cytometry, magnetic resonance imaging, transmission electron microscopy, etc. The binding was detected by molecular docking and molecular dynamics simulation.
Results
Both in vitro and in vivo models of cerebral ischemia/reperfusion (I/R) injury presented a sharp increase in NRP-1 expression. The expression of AAV-NRP-1 markedly ameliorated the cerebral I/R-induced damage to the motor function and restored the mitochondrial morphology. The expression of LV-NRP-1 alleviated mitochondrial oxidative stress and bioenergetic deficits. AAV-NRP-1 and LV-NRP-1 treatments increased the wingless integration (Wnt)-associated signals and β-catenin nuclear localization. The protective effects of NRP-1 were reversed by the administration of XAV-939.
Conclusions
NRP-1 can produce neuroprotective effects against I/R injury to the brain by activating the Wnt/β-catenin signaling pathway and promoting mitochondrial structural repair and functional recovery, which may serve as a promising candidate target in treating ischemic stroke.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.