ObjectiveTo explore the expressions of polo-like kinase 1(PLK1) and serine/threonine kinase 15 (STK15) mRNA and protein in colon cancer cells, and to explore the inhibitive effect of SBE13 and VX-680 for PLK1 protein and STK15 protein. MethodsOne kind of cervical cancer cells(Hela cells) and 3 kinds of colon cancer cells (HCT-116 cells, HT-29 cells, and CACO-2 cells) were selected for experiment. Expression levels of PLK1 mRNA, STK15 mRNA and its protein of 4 kinds of cells were detected by reverse transcription polymerase chain reaction(RT-PCR) and Western blot method respectively. Inhibitive effect of SBE13 and VX-680 were evaluated in vitro by methylthiazolyldiphenyl-tetrazolium bromide(MTT) assay in 4 kinds of cells, which divided into 5 groups, receiving Dulbecco's modification of Eagle's medium(DMEM), dimethylsulfoxide(DMSO), SBE13, VX-680, and SBE13+VX-680 respectively. ResultsCompared with Hela cells, expression levels of PLK1 mRNA, STK15 mRNA and its protein in HCT-116 cells,HT-29 cells, and CACO-2 cells were higher(P<0.05). ① Hela cells:Compared with DMEM group, the proliferative activity were not inhibited in SBE13 group, VX-680 group, and SBE13+VX-680 group(P>0.05). ② HCT-116 cells and HT-29 cells:Compared with DMEM group, the proliferative activity were inhibited in VX-680 group and SBE13+VX-680 group(P<0.05), but was not inhibited in SBE13 group(P>0.05). ③ CACO-2 cell:Compared with DMEM group, the proliferative activity were inhibited in SBE13 group, VX-680 group, and SBE13+VX-680 group(P<0.05). ConclusionsExpression levels of PLK1 mRNA, STK15 mRNA and its protein increase in HCT-116, HT-29, and CACO-2 cells compared with Hela cells. SBE13 and VX-680 can inhibit PLK1 and STK15 protein partly in colon cancer cell lines.
ObjectiveTo observe the influence of down-regulation of HtrA1 expression by small interfering RNA on light-injured human retinal pigment epithelium (RPE) cells. MethodsCultured human RPE cells(8th-12th generations)were exposed to the blue light at the intensity of (2000±500) Lux for 6 hours to establish the light injured model. Light injured cells were divided into HtrA1 siRNA group, negative control group and blank control group. HtrA1 siRNA group and negative control group were transfected with HtrA1 siRNA and control siRNA respectively. The proliferation of cells was assayed by CCK-8 method. Transwell test was used to detect the invasion ability of these three groups. Flow cytometry was used to detect the cell cycle and apoptosis. The expression of HtrA1 and vascular endothelial growth factor (VEGF)-A was detected by real time-polymerase chain reaction and Western blot respectively. ResultsThe mRNA and protein level of HtrA1 in the light injured cells increased significantly compared to that in normal RPE cells (t=17.62, 15.09; P<0.05). Compared with negative control group and blank control group, the knockdown of HtrA1 in HtrA1 siRNA group was associated with reduced cellular proliferation (t=6.37, 4.52), migration (t=9.56, 12.13), apoptosis (t=23.37, 29.08) and decreased mRNA (t=17.36, 11.32, 7.29, 4.05) and protein levels (t=12.02, 15.28, 4.98, 6.24) of HtrA1 and VEGF-A. Cells of HtrA1 siRNA group mainly remained in G0/G1 phase, the difference was statistically significant (t=6.24, 4.93; P<0.05). ConclusionKnockdown of HtrA1 gene may reduce the proliferation, migration capability and apoptosis of light-injured RPE cells, and decrease the expression of VEGF-A.
Objective To investigate the effects of exosomes from cultured human retinal pigment epithelium (ARPE-19) cells affected by oxidative stress on the proliferation and expression of vascular endothelial growth factor-A (VEGF-A) and Akt of ARPE-19 cells. Methods Culture ARPE-19 cells. The concentration of 2.5 μmol/L rotenone was selected to simulate oxidative stress and isolated ARPE-19-exosome. Exosomes were isolated by ExoQuick exosome precipitation solution. Transmission electron microscopy was used to identify the morphology of exosomes. Western blot was used to detect exosomes’ surface-specific maker protein CD63. ARPE-19 cells affected by oxidative stress were cultured with exosome as experimental group, normal ARPE-19 cells were cultured with exosome as control group. The cell proliferation was examined by methyl thiazolyl tetrazolium assay. Western blot and immunofluorescence assay were used to detect the expression levels of VEGF-A and Akt protein. Real-time quantitative polymerase chain reaction (RT-PCR) was used to detect the levels of VEGF-A mRNA and Akt mRNA. Results The diameter of normal ARPE-19-exosomes ranged from 50 to 150 nm. The isolated exosomes expressed CD63. AREP-19 cells were cultured with ARPE-19 (affected by rotenone)-exosome, the cell viability in experimental group was significantly reduced than in the control group. Green fluorescence was observed in the cytoplasm under fluorescence microscope. Compared with the control group, VEGF-A was up-regulated expressed and Akt was down-regulated expressed. Western blot results showed that, VEGF-A protein expression in the experimental group were higher than the control group. Akt protein expression in the experimental group were less than the control group. The difference was statically significant (t=3.822, 6.527;P＜0.05). RT-PCR results showed that VEGF-A mRNA expression levels was higher in the experimental group than the control group. Akt mRNA expression levels was lower in the experimental group than the control group. The difference was statically significant (t=8.805, −7.823;P＜0.05). Conclusions Exosomes from ARPE-19 cells affected by oxidative stress inhibit the proliferation of normal ARPE-19 cells, increase the expression of VEGF-A and reduce the expression of Akt.
ObjectiveTo summarize the biological function and molecular regulation mechanism of serine threonine tyrosine kinase 1 (STYK1) in tumor occurrence and development. MethodThe relevant literature about STYK1 and tumor progression in recent years was searched and reviewed. ResultsThe expression of STYK1 was up-regulated in a variety of tumors and was related to the prognosis. STYK1 might regulate the proliferation, apoptosis, migration, metastasis, aerobic glycolysis, drug resistance and other biological functions of tumor cells through MEK/ ERK, PI3K/AKT, JAK/STAT and their targeting proteins, and promote the malignant progress of tumors. Conclusion STYK1is expected to become a new target for the treatment of malignant tumors, but the molecular mechanism of its regulation of tumor progression and its upstream regulators need to be further explored.
Objective To analyze the metabolic characteristics of myocardial infarction (MI) using metabolomics to better understand its pathogenesis and to explore new therapeutic directions for MI. Methods Serum metabolites in ten acute MI mice and five sham-control mice were analyzed by UHPLC-QqQ/MS, and SPSS was used for statistical analysis. MetaboAnalyst 5.0 was used to analyze the metabolic pathways of the differential metabolites and build a metabolic network. Results One hundred and twenty-nine metabolites were detected by UHPLC-QqQ/MS. Significant serum metabolite differences were found between MI mice and normal controls. Fifty out of 129 metabolites in serum were associated with MI. In addition, the most important metabolic pathways were D-glutamate metabolism, alanine, aspartate and glutamate metabolism, glycine, serine and threonine metabolism, glyoxylate and dicarboxylate acid metabolism. ConclusionMetabolites in serine-related metabolic pathways reduce in serum in MI. We propose a new therapeutic direction for myocardial protection in MI.
Objective To observe the effect of high expression of polypyrimidine tract-binding protein-associated splicing factor (PSF) on low concentration of 4-hydroxynonenal (4-HNE) induced human retinal microvascular endothelial cells (HRMECs), and explore the possible mechanism. MethodsThe HRMECs cultured in vitro were divided into 4-HNE treated group, PSF overexpression group combined with 4-HNE group (PSF+4-HNE group), PSF overexpression+ML385 treatment combined with 4-HNE group (PSF+ML385+4-HNE group), and 4-HNE induced PSF overexpression group with LY294002 pretreatment (LY294002+4-HNE+PSF group). Cell culture medium containing 10 μmmol/L 4-HNE was added into 4-HNE treatment group, PSF+4-HNE group, PSF+ML385+4-HNE group for 12 hours to stimulate oxidative stress. 1.0 μg of pcDNA-PSF eukaryotic expression plasmid were transfected into PSF+4-HNE group and PSF+ML385+4-HNE group to achieve the overexpression of PSF. Also cells were pretreated with ML385 (5 μmol/L) for 48 hours in the PSF+ML385+4-HNE group, meanwhile within the LY294002+4-HNE+PSF group, after pretreatment with LY294002, cells were treated with plasmid transfection and 4-HNE induction. Transwell detects the migration ability of PSF to HRMECs. The effect of PSF on the lumen formation of HRMECs was detected by using Matrigel in vitro three-dimensional molding method. Flow cytometer was used to detect the effect of PSF overexpression on reactive oxygen (ROS) level in HRMECs. Protein immunoblotting was used to detect the relative expression of PSF, nuclear factor E2 related factor 2 (Nrf2), heme oxygenase-1 (HO-1) protein, and phosphoserine threonine protein kinase (pAkt) protein. The comparison between the two groups was performed using a t-test. ResultsThe number of live cells, migrating cells, and intact lumen formation in the 4-HNE treatment group and the PSF+4-HNE group were 1.70±0.06, 0.80±0.13, 24.00±0.58, 10.00±0.67, and 725.00±5.77, 318.7±12.13, respectively. There were significant differences in the number of live cells, migrating cells, and intact lumen formation between the two groups (t=12.311, 15.643, 17.346; P＜0.001). The results of flow cytometry showed that the ROS levels in the 4-HNE treatment group, PSF+4-HNE group, and PSF+ML385+4-HNE group were 816.70±16.67, 416.70±15.44, and 783.30±17.41, respectively. There were statistically significant differences between the two groups (t=16.311, 14.833, 18.442; P＜0.001). Western blot analysis showed that the relative expression levels of pAkt, Nrf2, and HO-1 proteins in HRMECs in the 4-HNE treatment group, PSF+4-HNE group and LY294002+4-HNE+PSF group were 0.08±0.01, 0.57±0.04, 0.35±0.09, 0.17±0.03, 1.10±0.06, 0.08±0.11 and 0.80±0.14, 2.50±0.07, 0.50±0.05, respectively. Compared with the PSF+4-HNE group, the relative expression of pAkt, Nrf2, and HO-1proteins in the LY294002+4-HNE+PSF group decreased significantly, with significant differences (t=17.342, 16.813, 18.794; P＜0.001). ConclusionPSF upregulates the expression of HO-1 by activating the phosphatidylinositol 3 kinase/Akt pathway and inhibits cell proliferation, migration, and lumen formation induced by low concentrations of 4-HNE.
HtrA serine peptidase 2 (HTRA2) is a serine protease existing in the mitochondrial gap. Among the four members of the human HtrA serine peptidase family, HTRA2 is the only protease with clear localization in the cell. It plays a dual role in the maintenance of mitochondrial homeostasis and the promotion of cell apoptosis. HTRA2 has been found to be associated with a variety of tumors. Meanwhile, the expression of HTRA2 can enhance the sensitivity of chemotherapy and radiotherapy, and can be used as a diagnostic and prognostic marker for malignant tumors and a target for combined therapy. This article reviews the structure, biological function and role of HTRA2 in malignant tumors, in order to provide clues and basis for early diagnosis and individualized treatment of tumor patients.