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991.
AIM To explore the effect of andrographolide (AND) on the growth and apoptosis of acute lymphoblastic leukemia (ALL) cells. METHODS CCK-8 assay was used to assess the viability of human acute lymphoblastic leukemia CEM-C1 cells treated with AND for 12 h, 24 h and 48 h. The cell morphological changes were observed by Wright-Giemsa staining. The cell apoptosis was detected by flow cytometry with annexin V-FITC/propidium iodide (PI) staining, and the cell cycle was examined by flow cytometry with PI staining. The expression levels of apoptosis-related proteins were examined by Western blot. The mitochondrial membrane potential (MMP) of the cells was determined by JC-1 assay. RESULTS The results of CCK-8 assay indicated that AND inhibited the viability of CEM-C1 cells in a dose- and time-dependent manner. After administration of AND for 24 h, CEM-C1 cells shrank, the cytoplasm turned red and the cell numbers were significantly reduced. Incubation of AND for 24 h resulted in G2-phase arrest and apoptosis. Treatment with AND for 24 h increased the protein levels of cleaved caspase-3, cleaved caspase-7 and Bax, and down-regulated Bcl-2 in the CEM-C1 cells (P<0.05). The ratios of cleaved caspase-3/caspase-3, cleaved caspase-7/caspase-7 and Bax/Bcl-2 were elevated with the increase in the concentration of AND. Collapsed MMP in CEM-C1 cells was observed after AND administration for 24 h. Treatment with AND in vivo suppressed the growth of the xenograft tumor and increased the protein level of cleaved caspase-3. CONCLUSION Andrographolide exerts growth-inhibitory and apoptosis-inducing effects on ALL cells both in vitro and in vivo.  相似文献   
992.
AIM: To investigate the effects of microRNA-485-5p (miR-485-5p) on the viability, migration and invasion abilities of hepatocellular carcinoma cells and the underlying mechanism. METHODS: The expression levels of sex determining region Y-box 5 (SOX5) mRNA and miR-485-5p in the hepatocellular carcinoma Hep3B cells were detected by RT-qPCR with normal hepatocyte THLE-3 as control. Western blot was used to measure the expression levels of SOX5, proliferating cell nuclear antigen (PCNA), Ki67, cyclin D1 and matrix metalloproteinase-2 (MMP-2). The viability of Hep3B cells was measured by MTT assay. The migration and invasion abilities of the Hep3B cells were detected by Transwell assay. Dual-luciferase reporter assay system was applied to verify the relationship between miR-485-5p and SOX5. RESULTS: Compared with the control cells, the expression level of miR-485-5p was decreased in hepatocellular carcinoma cells Hep3B, Huh7 and HCCLM3 (P<0.05), while the expression of SOX5 at mRNA and protein levels were significantly increased (P<0.05). Over-expression of miR-485-5p inhibited the viability, migration and invasion of Hep3B cells. miR-485-5p targeted the 3′-UTR of SOX5 and negatively regulated the expression of SOX5. Knocking-down of SOX5 expression inhibited the viability, migration and invasion of Hep3B cells. Over-expression of SOX5 partially reversed the inhibitory effect of miR-485-5p over-expression on the viability, migration and invasion of Hep3B cells. CONCLUSION: miR-485-5p inhibits the viability, migration and invasion of Hep3B cells by targeting SOX5 gene. miR-485-5p is a potential molecular target for hepatocellular carcinoma.  相似文献   
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XU Yan  SHU Shi-yu 《园艺学报》2020,36(7):1170-1177
AIM To study the effects of HET0016 on the proliferation and migration of microglia stimulated by lipopolysaccharide (LPS). METHODS Primary microglia from neonatal SD rats were isolated, purified and cultured. CCK-8 assay was performed to detect the effect of HET0016 on the viability of microglia after treatment with LPS. The levels of 20-hydroxyeicosatetraenoic acid (20-HETE), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were measured by ELISA. The proportion of S phase was evaluated by flow cytometry. The cell migration ability was detected by Transwell assay and scratch wound healing assay. The protein expression of NF-κB p50 and p65 was determined by Western blot. RESULTS LPS induced the increases in the proliferation and migration of microglia and the release of inflammatory cytokines (P<0.05). Compared with LPS group, HET0016 inhibited the cell proliferation and migration (P<0.05), decreased the levels of TNF-α and IL-1β (P<0.05), and reduced the expression of NF-κB p50 and p65 (P<0.05). CONCLUSION HET0016 has inhibitory effects on the proliferation and migration of microglia induced by LPS, and reduces the release of inflammatory cytokines. The mechanism may be related to NF-κB signaling pathway.  相似文献   
996.
AIM To investigate the role, clinical implications and the underlying mechanisms of Rab11-family interacting protein 4 (Rab11-FIP4) in colorectal cancer (CRC). METHODS The expression levels of Rab11-FIP4 in CRC tissues and corresponding paracancerous tissues were compared by immunohistochemistry, Western blot and RT-qPCR. The above methods were also used to detect the expression levels of Rab11-FIP4 in CRC cells under normal environment and hypoxia. The patiens were divided into Rab11-FIP4 high expression group (n=61) and Rab11-FIP4 low expression group (n=39) according to the immunohistochemical staining score.The overall survival and recurrence time of the 2 groups were compared by Kaplan-Meier survival analysis. HCT116 and LoVo cells with stable over-expression of Rab11-FIP4 were constructed using a lentiviral system. The cytological characteristics effects of Rab11-FIP4 over-expression in CRC cells were examined by CCK-8 assay, clonogenic assay and the Transwell assay. The co-immunoprecipitation was used to detect the correlation between Rab11-FIP4 and insulin-like growth factor 1 receptor (IGF1R). Human phosphokinase array was performed to investigate the signaling pathhway affected by IGF1R in CRC cells with increased expression of Rab11-FIP4. The relationship between Rab11-FIP4 and hypoxia-inducible factor 1α (HIF-1α) was analyzed by tissue microarrays and dual-luciferase reporter assay. RESULTS Rab11-FIP4 expression was up-regulated in CRC tissues and high expression of Rab11-FIP4 was associated with poor prognosis of the patients with CRC (P<0.05). Over-expression of Rab11-FIP4 promoted the viability, migration and invasion of CRC cells (P<0.05). High expression of Rab11-FIP4 regulated ERK1/2 and AKT signaling pathway via IGF1R (P<0.05). Hypoxia promoted the activation of HIF-1α on the Rab11-FIP4 promoter, thereby up-regulating the expression of Rab11-FIP4 (P<0.05). CONCLUSION Rab11-FIP4 may act as an oncogene to regulate migration and invasion of colorectal cancer cells through IGF1R.  相似文献   
997.
The cell wall composition and structure of the maize stalk directly affects its digestibility and in turn its feed value.Previous studies of stem quality have focused mostly on common maize germplasm,and few studies have focused on high-oil cultivars with high grain and straw quality.Investigation of the genetic basis of cell wall composition and digestibility of maize stalk using high-oil maize is desirable for improving maize forage quality.In the present study,a high-oil inbred line(By804)was crossed as male parent with the maize inbred line B73 to construct a population of 188 recombinant inbred lines(RILs).The phenotypes of six cell-wall-related traits were recorded,and QTL analysis was performed with a genetic map constructed with SNP markers.All traits were significantly correlated with one another and showed high broad-sense heritability.Of 20 QTLs mapped,the QTL associated with each trait explained 10.0%–41.1%of phenotypic variation.Approximately half of the QTL each explained over 10%of the phenotypic variation.These results provide a theoretical basis for improving maize forage quality by marker-assisted selection.  相似文献   
998.
AIM: To investigate the mRNA and protein expression of apoptotic protease-activating factor 1 (Apaf-1) in papillary thyroid carcinoma (PTC) and its relationship with cell proliferation.METHODS: The methods of real-time PCR, Western blot and immunohistochemistry were used to detect the mRNA and protein expression of Apaf-1 in PTC and tumor-adjacent tissues. The relationship between Apaf-1 expression and clinicopathological characteristics was analyzed. The effect of Apaf-1 on cell proliferation was verified by down-regulating the expression of Apaf-1 in CGTHW-3 cells.RESULTS: The mRNA and protein expression levels of Apaf-1 in the PTC tissue were significantly lower than those in the tumor-adjacent tissue (P<0.05). Down-regulation of Apaf-1 expression enhanced the proliferation of CGTHW-3 cells (P<0.05).CONCLUSION: The expression of Apaf-1 is low in PTC, and inhibition of its expression enhances the proliferation of CGTHW-3 cells. Apaf-1 may play a tumor suppressor role in PTC.  相似文献   
999.
AIM: To explore the influence of long non-coding RNA HOTAIR on the proliferation and apoptosis of acute lymphoblastic leukemia cells via the regulation of glucocorticoid receptor (GR).METHODS: The expression le-vels of HOTAIR and GR mRNA in human bone marrow stromal cell line HS-5 and human acute lymphoblastic leukemia cell lines MOLT-4, CCRF-CEM and CEM-C1 were examined by RT-qPCR. HOTAIR was knocked down by siRNA in acute lymphoblastic leukemia cells. CCK-8 assay was used to assess the cell viability, and the effect of si-HOTAIR on the proli-feration of CEM-C1 cells was evaluated by BrdU method. The effect of si-HOTAIR on apoptosis of CEM-C1 cells was examined by Hoechst 33342 staining and Caspase-Glo® 3/7 assay. Western blot was utilized to examine the protein level of GR.RESULTS: The expression level of HOTAIR in acute lymphoblastic leukemia cells was significantly increased as compared with normal human bone marrow stromal cells (P<0.01). The viability and proliferation of acute lymphoblastic cells was inhibited, the apoptosis was induced, and the anti-proliferation effect of dexamethasone on CEM-C1 cells was enhanced after knockdown of HOTAIR expression (P<0.01). The expression of GR was up-regulated at both mRNA and protein levels (P<0.01).CONCLUSION: Long non-coding RNA HOTAIR may modulate the viability, proliferation and apoptosis of acute lymphoblastic leukemia cells via a GR regulatory way.  相似文献   
1000.
AIM:To explore the effects of neuraminidase 3 (NEU3) on the viability, invasion and apoptosis of human prostate cancer DU145 cells and the molecular mechanism. METHODS:The human prostate cancer DU145 cells were divided into blank control group and treatment group. The cells in treatment group were treated with either neuraminidase inhibitor DANA, or NEU3 small interfering RNA (siRNA) to knock down the expression of NEU3. The cell viability was measured by CCK-8 assay. The cell invasion ability was detected by Transwell assay. The effects of the treatments on the mRNA level of Bcl-2 were detected by qPCR. The effects of the treatments on the protein levels of matrix metalloproteinase 2 (MMP2) and apoptotic inhibitory protein Bcl-2 were determined by Western blot. Apoptosis of the cells was analyzed by flow cytometry. RESULTS:The protein level of NEU3 and the apoptotic rate in DANA group were not significantly different from those in blank control group. The viability of DANA-treated DU145 cells was increased, and the invasion ability, MMP2 protein level, and Bcl-2 mRNA and protein levels were all decreased in these cells, compared with blank control group. On the other hand, the levels of NEU3 protein and Bcl-2 mRNA and protein in NEU3 siRNA group were significantly decreased compared with blank control group, while the viability and apoptotic rate of the cells with NEU3 siRNA transfection were increased (P<0.05). However, the protein expression of MMP2 and the invasion ability of the cells were not significantly changed after NEU3 siRNA treatment. CONCLUSION:The inhibition of NEU3 in enzyme activity and expression decreases the viability, and enhances the apoptosis of human prostate cancer DU145 cells. However, it has no obvious effect on the invasion ability of DU145 cells.  相似文献   
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