Effect of serum amyloid A on invasion,migration and MAPK signaling pathway in osteosarcoma cells

AIM: To investigate the effect of silencing of serum amyloid A (SAA) on the viability, apoptosis, migration and mitogen-activated protein kinase (MAPK) signaling pathway in osteosarcoma U2OS cells. METHODS: Small interfering RNA (siRNA) targeting SAA was transfected into U2OS cells to silence the expression of SAA gene. The U2OS cells were divided into blank control group, negative control group, and experimental group. The cells in negative control group and experimental group were transfected into negative control siRNA and SAA-siRNA, respectively. The cells in blank control group were without any treatment. The viability of the cells was measured by MTT assay and the apoptotic rate was analyzed by flow cytometry with Annexin V-FITC/PI double staining. The migration and invasion abilities of the cells were detected by Transwell chamber assay. The protein levels of SAA, phosphorylated p38 MAPK (p-p38 MAPK) and phosphorylated c-Jun N-terminal kinase (p-JNK) in the cells were determined by Western blot. RESULTS: The protein expression of SAA in SAA-siRNA group was significantly lower than that in blank control group (P<0.05). Compared with blank control group, the cell viability in SAA-siRNA group was significantly decreased (P<0.05), the apoptotic rate was significantly increased (P<0.05), and the invasion and migration abilities were significantly decreased (P<0.05). The protein levels of p-p38 MAPK and p-JNK in SAA-siRNA group were significantly lower than those in blank control group (P<0.05), and no significant difference of total JNK and p38 protein levels was observed. CONCLUSION: Silencing of SAA expression inhibits the viability of osteosarcoma cells, induces apoptosis and decreases the migration of osteosarcoma cells, which may be related to the activation of MAPK signaling pathway.     

Effects of andrographolide on invasion and apoptosis of ovarian cancer SKOV-3 cells

AIM:To investigate the effects of andrographolide on the invasion and apoptosis of ovarian cancer cell line SKOV-3,and to explore the possible mechanisms.METHODS:SKOV-3 cells were treated with different concentrations (0,5,10,20 or 40 μmol/L) of andrographolide for different time (12,24,36 or 48 h),and then the cell viability was determined by CCK-8 assay.The cell invasion ability was analyzed by Transwell assay and cell apoptosis was detected by TUNEL staining.The protein levels of p-PI3K,p-Akt and p-mTOR were examined by Western blot.RESULTS:The results of CCK-8 assay revealed that andrographolide inhibited the growth of SKOV-3 cells in a dose-and time-dependent manner.Treatment with andrographolide at 20 μmol/L for 36 h significantly decreased the invasion ability of SKOV-3 cells,while increased cell apoptosis.In addition,the protein levels of p-PI3K,p-Akt and p-mTOR were reduced after andrographolide treatment.CONCLUSION:Andrographolide inhibits the growth and invasion of ovarian cancer SKOV-3 cells by suppression of PI3K/Akt/mTOR signaling pathway.     

Effect of andrographolide on oral squamous cell carcinogenesis

AIM：To study the effect of andrographolide (Andro) on oral squamous cell carcinogenesis. METHODS：Chemical-induced hamster buccal pouch cancer model was used. The tumor cell proliferation, apoptosis and microvessel density (MVD) were detected by immunohistochemical staining. RESULTS：Compared with control group, the tumor volume, MVD and tumor cell proliferation in Andro group were significantly decreased. The cell apoptotic cell number in Andro group was higher than that in control group. Caspase-3 was also activated in Andro group. CONCLUSION:Andro inhibits tumor growth by suppressing proliferation, decreasing MVD and promoting apoptosis in the hamster buccal pouch. Furthermore, Andro promotes tumor cell apoptosis through caspase-3 pathway.     

S100A6 promotes proliferation and migration of human osteosarcoma cell line 143B through PI3K/Akt signaling pathway

AIM: To investigate the effect of PI3K/Akt signaling pathway on S100A6-induced proliferation and migration of human osteosarcoma cell line 143B. METHODS: Recombinant human S100A6 protein (rhS100A6) was prepared. The 143B cells were treated with rhS100A6 in the presence or absence of PI3K inhibitor (LY294002 or wortmannin) exposure. The final concentrations of rhS100A6, LY294002 and wortmannin were 30 mg/L, 10 μmol/L and 0.5 μmol/L, respectively. The expression levels of total Akt (t-Akt) and phosphorylated Akt (p-Akt) in the 143B cells were analyzed by Western blotting. The cell proliferation and migration were determined by MTT and Transwell assays. RESULTS: rhS100A6 protein was successfully prepared, and significantly increased the proliferation and migration of 143B cells (P<005). rhS100A6 up-regulated the phosphorylation of Akt in 143B cells (P<005). Compared with rhS100A6 group, the level of p-Akt in 143B cells and the proliferation and migration of the cells were decreased in combined treatment group of rhS100A6 with LY294002 or wortmannin (P<005), where the proliferation rate at different time points dropped from 10.3% to 69.7% (P<005), and the migration rate dropped from 34.9% to 47.7% (P<005). CONCLUSION: To some extent, S100A6 promotes proliferation and migration of human ostersarcoma cell line 143B through PI3K/Akt signaling pathway.     

Molecular mechanisms of Belinostat inhibiting viability of osteosarcoma cells

AIM: To observe the effect of histone deacetylase inhibitor (HDACi) Belinostat on the viability of osteosarcoma cells and to study the underlying mechanism. METHODS: Osteosarcoma cell lines SAOS-2 and U2OS were incubated with Belinostat at different concentrations in vitro. The viability of the cells was measured by MTT assay. The activity of caspase-3/-7 and the DNA fragmentation were detected by fluorescence probe and ELISA, respectively. Western blot was used to detect the levels of histone acetylation, expression of PTEN, caspase-3, Bcl-xL and Akt, and phosphorylation of glycogen synthetase kinase 3β (GSK-3β) and Akt. Finally, the cells were incubated with Belinostat and doxorubicin at different concentrations, and then the combination index (CI) was calculated by MTT. RESULTS: Belinostat at 0.5, 1, 2.5 and 5 μmol/L inhibited the viability of U2OS cells and SAOS-2 cells in a dose-dependent manner, induced DNA fragmentation, enhanced caspase-3/-7 activity, and promoted the activation of caspase-3. At the same time, in the SAOS-2 cells, the expression of Bcl-xL was reduced, and the acetylation of histones H3 and H4 was increased. The results of Western blot showed that phosphorylation levels of Akt and GSK-3β in U2OS cells and SAOS-2 cells were decreased significantly after treatment with Belinostat (P<0.05). MTT results showed that combination of Belinostat and doxorubicin further reduced the viability of U2OS and SAOS-2 cells (CI<1). CONCLUSION: Belinostat inhibits the viability of osteosarcoma cells treated with doxorubicin, and the mechanism may be related to the inhibition of Akt signaling pathway.     

Effect of CFTR on viability and apoptosis of acute leukemia cells and its related mechanisms

AIM: To investigate the expression of cystic fibrosis transmembrane conductance regulator (CFTR) in acute myeloid leukemia (AML) and its effect on the biological function of human erythroleukemia cell line TF1, and to explore the underlying mechanism. METHODS: The abundance of CFTR in the bone marrow mononuclear cells of patients with AML was measured by real-time PCR. After TF1 cells were incubated with CFTR specific inhibitor CFTRinh-172, cell viability, cell cycle distribution and cell apoptosis were analyzed by CCK-8 assay and flow cytometry. The Wnt signaling pathway-related proteins were determined by Western blot. RESULTS: CFTR was highly expressed in both patients with AML and leukemia cell lines. After incubated with CFTRinh172, the viability of TF1 cells was decreased, the proportion of the cells in G₀/G₁ phase was increased, while that in S phase declined (P<0.05). Furthermore, the cells treated with CFTRinh-172 exhibited higher apoptotic rate, accompanied with lower protein expression of β-catenin, c-Myc and cyclin D1 (P<0.05). CONCLUSION: CFTR expression is dramatically increased in AML. Inhibition of CFTR restrains the growth and promotes the apoptosis of TF1 cells via classical Wnt signaling pathway.     

Growth-inhibitory and apoptosis-inducing effects of andrographolide on acute lymphoblastic leukemia cells

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.     

Effect of Wnt/β-catenin signaling pathway regulated by HDAC1 on apoptosis of breast cancer cells

AIM: To study the effect of histone deacetylase 1 (HDAC1) on the apoptosis of breast cancer cells.METHODS: The expression of HDAC1 at mRNA and protein levels in normal mammary epithelial cell line MCF-10A and breast cancer cell lines BT549, MCF-7 and MDA-MB-231 was measured by RT-qPCR and Western blot. HDAC1 siRNA was transfected into MDA-MB-231 cells, and then RT-qPCR and Western blot were used to determine the expression level of HDAC1. The cell viability was measured by MTT assay, and apoptosis was analyzed by flow cytometry. The protein levels of β-catenin, c-Myc, cyclin D1 and cleaved caspase-3 were determined by Western blot. Breast cancer cells with HDAC1 knockdown were treated with Wnt/β-catenin signaling pathway activator, and then the cell viability and apoptosis were measured.RESULTS: The expression of HDAC1 at mRNA and protein levels in BT549, MCF-7 and MDA-MB-231 cells was significantly higher than that in normal mammary epithelial cell line MCF-10A, and the highest expression level of HDAC1 was observed in MDA-MB-231 cells (P<0.05). HDAC1 siRNA reduced the expression of HDAC1 at mRNA and protein levels in the breast cancer cells. The viability of MDA-MB-231 cells was decreased after knockdown of HDAC1 expression, the apoptotic rate was increased, the protein level of cleaved caspase-3 in the cells was elevated, and the protein levels of β-catenin, c-Myc and cyclin D1 were decreased (P<0.05). Wnt/β-catenin signaling pathway activator reversed HDAC1 knockdown-induced apoptosis and decrease in viability of MDA-MB-231 cells, and reduced the protein level of cleaved caspase-3.CONCLUSION: Knockdown of HDAC1 expression induces apoptosis of breast cancer cells by inhibiting the activation of Wnt/β-catenin signaling pathway.     

Effect of EZH2 regulating Wnt/β-catenin signaling pathway on apoptosis of brain glioma cells

AIM: To investigate the effect of enhancer of zeste homolog 2 (EZH2) regulating Wnt/β-catenin signaling pathway on the apoptosis of brain glioma cell lines. METHODS: The expression level of EZH2 in glioma cell lines U87, H4 and U251 and normal human astrocytes (NHA) was detected by RT-qPCR and Western blot. The EZH2 siRNA and siRNA control were transfected into the H4 cells. The cell viability was measured by MTT assay. The apoptosis was analyzed by flow cytometry. Caspase-3 activity was detected by spectrophotometry. The expression levels of the key protein β-catenin of the Wnt/β-catenin signaling pathway and the downstream target molecule c-Myc were determined by Western blot. After the H4 cells transfected with EZH2 siRNA were treated with an activator of Wnt/β-catenin signaling pathway, the apoptosis rate was measured by flow cytometry, and the expression of β-catenin and c-Myc was determined by Western blot. RESULTS: The mRNA and protein expression levels of EZH2 in the glioma cell lines U87, H4 and U251 were significantly higher than those in NHA (P<0.05). The expression of EZH2 at mRNA and protein levels in the H4 cells was higher than that in U87 cells and U251 cells (P<0.05). EZH2 siRNA obviously inhibited the expression of EZH2 at mRNA and protein levels in the H4 cells. Knockdown of EZH2 expression decreased the viability of H4 cells, the apoptotic rate was significantly increased, and the activity of caspase-3 was significantly increased in the cells (P<0.05). Knockdown of EZH2 expression also inhibited the expression of β-catenin and c-Myc. The activator of Wnt/β-catenin signaling pathway reduced the apoptosis rate of H4 cells induced by down-regulation of EZH2, and reduced the activity of caspase-3 in the cells. CONCLUSION: EZH2 is over-expressed in glioma cells. Down-regulation of EZH2 expression induces apoptosis of glioma cells by inhibiting the activation of Wnt/β-catenin signaling pathway.     

Effect of ixazomib on apoptosis and NF-κB signaling pathway in pancreatic cancer cells

AIM:To investigate the effects of ixazomib on the apoptosis and NF-κB signaling pathway in pancreatic cancer cells. METHODS:Human pancreatic cancer cell lines CFPAC-1 and PANC-1 were cultured, and the cells were treated with ixazomib at 0, 10, 20, 30 and 40 nmol/L for 12, 18, 24 and 48 h. The expression of NF-κB p65, IκB kinase (IKK), Bax and caspase-3 in the cells at mRNA and protein levels was determined by RT-qPCR and Western blot. The cell viability was measured by CCK-8 assay. The apoptosis was analyzed by flow cytometry. RESULTS:Treatment with ixazomib at 10~40 nmol/L inhibited the viability of PANC-1 cells and CFPAC-1 cells, and the inhibitory rate was increased significantly with the increases in the concentration and time (P<0.05). Compared with the control cells, treatment with ixazomib significantly increased the apoptotic rates of PANC-1 cells and CFPAC-1 cells in a dose- dependent manner (P<0.05), and significantly decreased the mRNA expression levels of NF-κB p65 and IKK in the PANC-1 cells and CFPAC-1 cells (P<0.05), while the mRNA expression levels of apoptotic factors Bax and caspase-3 in the PANC-1 cells and CFPAC-1 cells were significantly increased (P<0.05). The results of Western blot showed that treatment with ixazomib significantly decreased the protein levels of NF-κB p65 and IKK in the PANC-1 cells and CFPAC-1 cells (P<0.05), which was consistent with the results of mRNA expression. The protein levels of apoptosis factors Bax and caspase-3 in the CFPAC-1 cells were significantly increased (P<0.05), and the protein level of caspase-3 in the PANC-1 cells was increased significantly (P<0.05). However, Bax protein did not increase significantly in 10 nmol/L ixazomib group. CONCLUSION:Ixazomib, a proteasome inhibitor, inhibits the viability of pancreatic cancer cells and promotes apoptosis by inhibiting the activation of NF-κB signaling pathway in a time- and dose-dependent manner.     

Nisin induces apoptosis of human osteosarcoma MG63 cells via oxidative stress

AIM To investigate the effect of nisin on apoptosis of human osteosarcoma MG63 cells and its related oxidative stress mechanism. METHODS The MG63 cells were cultured in the medium containing different concentrations of nisin with or without antioxidant N-acetyl-L-cysteine （NAC）. The cell viability was measured by CCK-8 assay. Apoptosis was analyzed by flow cytometry with annexin-V/PI staining. The production of intracellular reactive oxygen species （ROS） was detected by redox-sensitive dye 2',7'-dichlorofluorescein diacetate （DCFH-DA）. The 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl benzimidazolyl carbocyanine iodide （JC-1） was used to detect the changes of mitochondrial membrane potential （MMP）. The protein levels of apoptosis-associated molecules Bax, Bcl-2 and cleaved caspase-3 were determined by Western blot. RESULTS Nisin decreased the viability of MG63 cells and promoted the apoptosis in a dose-dependent manner. It also up-regulated the protein level of cleaved caspase-3, increased the protein expression ratio of Bax/Bcl-2, triggered a large amount of intracellular ROS generation and reduced the MMP （P<0.05）. Moreover, antioxidant NAC significantly inhibited nisin-induced apoptosis of MG63 cells, down-regulated the protein level of cleaved caspase-3, decreased Bax/Bcl-2 ratio, reduced intracellular ROS level, and restored the MMP （P<0.05）. CONCLUSION Nisin may promote oxidative stress in human osteosarcoma cells, activate mitochondrial apoptosis pathway, and eventually induce apoptosis.     

Protective effect of paeoniflorin on nerve cells in APP/PS1 mice and its mechanism

AIM: To investigate the therapeutic and preventive effects of paeoniflorin (PF) on APP/PS1 mice, and to explore the possible mechanism. METHODS: Fifteen male 5-month-old APP/PS1 non-dominant mice were chosen as normal control group, 15 male 5-month-old APP/PS1 double transgenic mice were used as model group, and 15 male 5-month-old APP/PS1 double transgenic mice treated with 5 mg/kg PF by intraperitoneal injection were allocated in administation group. The learning and memory ability of the mice in each group was detected by Morris water maze. The apoptosis was assessed by TUNEL fluorescence staining. The protein expression of PI3K, Akt, p-PI3K, p-Akt, caspase-3, caspase-9, Bcl-2 and Bax in cerebral cortex and hippocampus was detected by Western Blot. The protein expression levels and distribution of caspase-3 and caspase-9 were detected by immunohistochemistry. RESULTS: (1) Compared with normal control group, the learning and memory ability declined in APP/PS1 model group. Compared with APP/PS1 model group, PF obviously improve the ability of learning and memory in mice. (2) Compared with normal control group, the apoptosis of nerve cells in APP/PS1 model group significantly increased and distributed in wider areas, while that in PF group was reduced (P<0.05). (3) Compared with APP/PS1 model group, PF could significantly lower pro-apoptotic factors, caspase-3, caspase-9 and Bax (P<0.05), and increase the expression of anti-apoptotic factors, p-PI3K, p-Akt and Bcl-2 (P<0.05). CONCLUSION: PF can up-regulate the expression of Bcl-2 and down-regulate the expression levels of caspase-9, caspase-3 and Bax via the activation of PI3K/Akt pathway, thereby inhibiting the nerve cell apoptosis and protecting the nerve cells, so as to treat neurodegenerative diseases.     

Tanshinone ⅡA induces apoptosis via JNK signaling pathway in human osteosarcoma HOS cells

AIM: To explore the effect of tanshinone ⅡA on human osteosarcoma HOS cells and the underlying mechanism.METHODS: The cell viability and the appropriate dose of tanshinone ⅡA were determined by CCK-8 assay. Colony formation assay and Transwell assay were used to investigate the proliferation and migration abilities of the HOS cells treated with tanshinone ⅡA. The apoptosis of the HOS cells was monitored by Hoechst 33258 staining, transmission electron microscopy and flow cytometry. The protein levels of apoptosis-related molecules and JNK signaling-associated proteins were determined by Western blot. Meanwhile, a JNK inhibitor was added for confirming the relationship between the pathway and apoptosis mentioned above.RESULTS: Tanshinone ⅡA inhibited both HOS cell proliferation and migration in a dose-and time-dependent manner. Exposure of the HOS cells to tanshinone ⅡA resulted in the activation of apoptosis. Tanshinone ⅡA treatment increased the protein levels of cleaved caspase-3, Bax and JNK signaling-associated proteins, and decreased the protein level of Bcl-2, which were reversed by JNK inhibitor SP600125. Moreover, the result of CCK-8 assay revealed that tanshinone ⅡA-induced cell death was alleviated by JNK inhibitor.CONCLUSION: Tanshinone ⅡA induces cell growth inhibition and the activation of apoptosis via JNK signaling pathway in human osteosarcoma HOS cells.     

Long non-coding RNA TTTY15 expression in osteosarcoma and its effect on viability and invasion ability of osteosarcoma cells

AIM:To observe the expression of long noncoding RNA TTTY15 in osteosarcoma tissues and cell lines and to explore its effect on the viability and invasion ability of osteosarcoma cell lines. METHODS:qPCR was used to detect the expression of TTTY15 in 11 cases of osteosarcoma and its adjacent tissues. The mRNA levels of TTTY15 in osteosarcoma cell lines (143B, Saos2, MG-63, U2OS and HOS) and human osteoblast cell line hFOB1.19 were also tested. TTTY15 was down-regulated after transfected with small interfering RNA in MG-63 cells, the cell line with the highest level of TTTY15. The effect of TTTY15 knockdown on the viability of MG-63 cells was measured by CCK-8 assay. The cell cycle distribution was analyzed by flow cytometry. The effect of TTTY15 knockdown on the cell invasion ability was detected by Transwell assay. The levels of miR-216b-5p and FOXM1 mRNA were detected by qPCR, and the changes of the related proteins were determined by Western blot. RESULTS:Compared with the adjacent tissues, the expression of TTTY15 increased in the osteosarcoma tissues (P<0.01). Compared with the human osteoblast cell line, the expression of TTTY15 increased in the osteosarcoma cell lines (P<0.05), and the level of TTTY15 in the MG-63 cells was the highest (P<0.01). After knockdown of TTTY15 expression in the MG-63 cells, the cell viability was decreased (P<0.05), cell cycle progression was inhibited (P<0.01), and the cell invasion ability was decreased (P<0.01). The expression of miR-216b-5p was increased (P<0.01) and the expression of FOXM1 mRNA was decreased (P<0.01). The protein expression of FOXM1, CDK4, cyclin D1, MMP-2 and N-cadherin was decreased, while the protein expression of E-cadherin was increased (P<0.05). CONCLUSION:The expression of TTTY15 is increased in the osteosarcoma tissues and cell lines. The low expression of TTTY15 inhibits the cell viability and invasion ability of osteosarcoma cells. The possible mechanism is that the knockdown of TTTY15 expression results in the increase in miR-216b-5p expression and the down-regulation of FOXM1 expression.     

Effect of metformin combined with paclitaxel on apoptosis and AMPK signaling in human breast cancer cells

AIM:To investigate the effect of metformin combined with paclitaxel on the viability and apoptosis of breast cancer cell line MCF-7 and its possible mechanism. METHODS:MCF-7 cells were treated with metformin at different concentrations (2, 5, 10, 20, 40 and 80 mmol/L) and in vitro cultured. The viability of MCF-7 cells was measured by MTT assay. Metformin at 2 mmol/L or paclitaxel at 2.4 mg/L alone or in combination was used to treat the cells, and compound C, an inhibitor of adenosine monophosphate-activated protein kinase (AMPK) signaling transduction pathway, was also used. The cells were divided into control group, metformin group, paclitaxel group, combination group, and combination +compound C group. The apoptosis of the cells was analyzed by flow cytometry. The expression of Bax, Bcl-2 and caspase-3 at mRNA and protein levels was determined by RT-qPCR and Western blot. The protein levels of AMPK and P21 were examined by Western blot. RESULTS:Metformin at different concentrations (2, 5, 10, 20, 40 and 80 mmol/L) significantly inhibited the cell viability in a concentration-dependent manner (P<0.05). Compared with control group, treatment with metformin at 2 mmol/L or paclitaxel at 2.4 mg/L alone or in combination significantly inhibited the cell viability, induced apoptosis (P<0.05), decreased the level of Bcl-2 (P<0.05), increased the levels of Bax and caspase-3 (P<0.05), and promoted the protein expression of AMPK and P21 (P<0.05). The effects of metformin and paclitaxel in combination were better than those of single drug treatment, while AMPK inhibitor weaken these effects. CONCLUSION:Metformin combined with paclitaxel inhibits the viability and induces the apoptosis of breast cancer MCF-7 cells by activating AMPK signaling pathway and regulating apoptosis signaling pathway.     

Effects of BCL6B on proliferation and migration of human colorectal carcinoma LoVo cells and its potential mechanism

AIM: To detect the endogenous expression of B-cell leukemia/lymphoma 6 member B (BCL6B) in FHC and LoVo cells, and to investigate the effects of BCL6B on proliferation and migration of LoVo cells for further exploring the underlying mechanism. METHODS: The endogenous expression of BCL6B in the FHC and LoVo cells was detected by RT-PCR and Western blot. The methods of MTT assay, colony formation assay, wound healing assay and Transwell chamber experiment were employed to examine the biological functions of BCL6B in the LoVo cells. The mRNA and protein levels of BCL6B, cyclin D1 and matrix metalloproteinase-9 (MMP-9) were determined by RT-PCR and Western blot, respectively. The level of phosphorylated protein kinase B (p-AKT) was detected by Western blot. RESULTS: BCL6B expression was notably repressed in the LoVo cells as compared with the FHC cells, which were significantly increased by transfection with pcDNA3.1-BCL6B. The abilities of proliferation and migration of the LoVo cells at 72 h were inhibited by 28.33%(P<0.01) and 36.11%(P<0.05) in BCL6B group. The mRNA levels of cyclin D1 and MMP-9 in the cells of BCL6B group were decreased by 39.90%(P<0.01) and 77.36% (P<0.05), and the protein levels of cyclin D1, MMP-9 and p-AKT were reduced by 44.00%(P<0.05), 47.06%(P<0.01) and 32.88% (P<0.05), respectively. CONCLUSION: BCL6B inhibits proliferation and migration of the LoVo cells, and the PI3K/AKT signaling pathway is involved in this process.     

Crosstalk between Wnt/β-catenin and NF-κB signaling #br# pathways during wound healing

Both Wnt/β-catenin and NF-κB signaling pathways are conserved pathways that regulate a variety of biological processes throughout the development and adult lifetime of mammals. Recent findings suggest that the 2 signaling pathways can cross-regulate each other. Several studies show that there are both positive and negative regulations between the 2 pathways. Some major components are involved in the cross-regulation of the 2 pathways such as Wnt proteins, DKK1, E-cadherin, GSK-3β, IKKs/IκB and so on. By reviewing the literature, we conjecture that the crosstalk between the 2 pathways regulate the wound healing process by intervening in the inflammation, fibroblast and angiogenesis, but the concrete mechanism is still unknown.     

Protective effect of curcumin on MRL/lpr mice with lupus nephritis and its mechanism

AIM To observe the effect of curcumin （Cur） on lupus nephritis （LN） and its possible mechanism. METHODS Thirty 10-week-old MRL/lpr lupus mice were randomly divided into MRL/lpr group, Cur-L and Cur-H group with 10 mice in each group, and C57BL/6 mice （n=10） served as normal control （NC） group. The mice in Cur-L group and Cur-H group were given intragastric administration of Cur at 100 and 200 mg·kg^-1·d^-1 for 12 weeks, respectively, and the same volume of normal saline was given to the mice in NC group and MRL/lpr group. The urine protein was detected, and the morphological changes of the renal tissue were observed by HE staining after treatment. The levels of serum creatinine （SCr）, blood urea nitrogen （BUN） and serum anti-double-stranded DNA （dsDNA）, and interleukin-1β （IL-1β）, IL-6 and tumor necrosis factor-α （TNF-α） levels in serum and renal tissues were detected. The protein levels of p-IκB, NF-κB, NLRP3 and caspase-1 in the renal tissues were determined by Western blot. RESULTS Compared with MRL/lpr group, the content of urine protein in Cur groups was significantly reduced, and the renal injury was relieved. The SCr, BUN, serum anti-dsDNA, and the serum and renal levels of IL-1, IL-6 and TNF-α were all significantly reduced, and the protein levels of p-IκB, NF-κB, NLRP and caspase-1 in the renal tissue were significantly decreased （P<0.05）. CONCLUSION Cur has a certain protective effect on the kidney of MRL/lpr mice, and its mechanism may be related to the inhibition of NF-κB and NLRP3 signaling pathways.     

Effect of lentinan on apoptosis and PI3K/AKT signaling pathway in leukemic HL-60 cells in vitro

AIM:To study of the regulatory effect of lentinan on human leukemic HL-60 cell apoptosis and its effect on PI3K/AKT signaling pathway in HL-60 cells in vitro.METHODS:Lentinan at concentrations of 0 mg/L, 15 mg/L, 30 mg/L and 45 mg/L was applied to HL-60 cells cultured to the logarithmic phase in vitro, and the inhibitory effect of lentinan on the viability of HL-60 cells was measured by MTT assay after 24 h, 48 h and 72 h. The apoptosis induced by lentinan was analyzed by flow cytometry. The protein levels of cleaved PARP, cleaved caspase-9, cleaved caspase-3, cleaved caspase-8, cytochrome C, PI3K, AKT and p-AKT were determined by Western blot. After treatment with PI3K inhibitor LY294002 at 5 mg/L for 72 h, the apoptosis of HL-60 cells was analyzed by flow cytometry. RESULTS:The viability of HL-60 cells was inhibited after treatment with lentinan at concentrations of 15 mg/L, 30 mg/L and 45 mg/L for 24 h, 48 h and 72 h in concentration-dependent and time-dependent manners (P<0.05). The apoptosis of HL-60 cells was promoted after treatment with lentinan (15 mg/L, 30 mg/L and 45 mg/L) for 72 h in a concentration-dependent manner (P<0.05). The protein levels of cleaved PARP, cleaved caspase-9, cleaved caspase-3 and cytoplasmic cytochrome C in the HL-60 cells induced by 30 mg/L lentinan were increased significantly with the increase in the treatment time (P<0.05), but caspase-8 did not show any change. The protein levels of PI3K, AKT and p-AKT were decreased obviously with the increase in the lentinan concentration (P<0.05). Treatment of HL-60 cells with LY294002, a PI3K pathway inhibitor, produced apoptosis-inducing effect similar to lentinan (P<0.05). CONCLUSION:Lentinan induces HL-60 cell apoptosis by inhibiting PI3K/AKT signaling pathway.