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ObjectiveTo investigate the effects of hydroxycamptothecin liposomes （LHCPT） on myocardial fibrosis in rats with heart failure by regulating the sphingosine kinase 1 （SphK1）/sphingosine-1-phosphate （S1P） signaling pathway. MethodsSD rats were divided into control group， model group， hydroxycamptothecin （HCPT） group， LHCPT group， captopril group， and LHCPT+K6PC-5 （SphK1 activator） group， with 12 rats in each group. The heart failure rat models in all groups except the control group were established by intraperitoneal injection of doxorubicin and then the corresponding drugs were given once a day. After four weeks， we applied color Doppler ultrasound to detect left ventricular end systolic diameter （LVESD）， left ventricular end diastolic diameter （LVEDD）， and left ventricular ejection fraction （LVEF） in rats； HE and Masson staining for myocardial pathological damage and myocardial fibrosis in rats， respectively； ELISA method for the levels of tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6） in rat myocardial tissues； qRT-PCR for the expression of transforming growth factor-β1 （TGF-β1）， type I collagen （Collagen I）， and type Ⅲ collagen （Collagen Ⅲ） in rat myocardial tissues； Western blot for the expression of SphK1 and S1P proteins in rat myocardial tissues. ResultsCompared with the control group， the model group showed severe myocardial pathological damage and myocardial fibrosis， increased LVESD， LVEDD， levels of TNF-α and IL-6， expression of TGF-β1， Collagen I， Collagen Ⅲ， SphK1， S1P and decreased LVEF （P<0.05）. Compared with the model group， the HCPT group， LHCPT group and captopril group showed alleviated myocardial pathological damage and myocardial fibrosis， decreased LVESD， LVEDD， levels of TNF-α and IL-6， expression of TGF-β1， Collagen I， Collagen Ⅲ， SphK1， S1P and increased LVEF （P<0.05）. Compared with the LHCPT group， the LHCPT+K6PC-5 group showed aggravated myocardial pathological damage and myocardial fibrosis， increased LVESD， LVEDD， levels of TNF-α and IL-6， expression of TGF-β1， Collagen I， Collagen Ⅲ， SphK1， S1P and decreased LVEF （P<0.05）. ConclusionLHCPT may inhibit myocardial fibrosis in heart failure rats by inhibiting the SphK1/S1P signaling pathway.
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OBJECTIVE@#To elucidate the renoprotective effect of resveratrol (RSV) on sphingosine kinase 1 (SphK1) signaling pathway and expression of its downstream molecules including activator protein 1 (AP-1) and transformation growth factor-β1 (TGF-β1) in lipopolysaccharide (LPS)-induced glomerular mesangial cells (GMCs).@*METHODS@#The rat GMCs line (HBZY-1) were cultured and randomly divided into 5 groups, including control, LPS (100 ng/mL), and 5, 10, 20 µmol/L RSV-treated groups. In addition, SphK1 inhibitor (SK-II) was used as positive control. GMCs were pretreated with RSV for 2 h and treated with LPS for another 24 h. GMCs proliferation was determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay. The proteins expression of SphK1, p-c-Jun and TGF-β1 in GMCs were detected by Western blot, and DNA-binding activity of AP-1 was performed by electrophoretic mobility shift assay (EMSA). The binding activity between RSV and SphK1 protein was detected by AutoDock Vina and visualized by Discovery Studio 2016.@*RESULTS@#LPS could obviously stimulate GMCs proliferation, elevate SphK1, p-c-Jun and TGF-β1 expression levels and increase the DNA-binding activity of AP-1 (P<0.05 or P<0.01), whereas these effects were significantly blocked by RSV pretreatment. It was also suggested that the effect of RSV was similar to SK-II (P>0.05). Moreover, RSV exhibited good binding affinity towards SphK1, with docking scores of -8.1 kcal/moL and formed hydrogen bonds with ASP-178 and LEU-268 in SphK1.@*CONCLUSION@#RSV inhibited LPS-induced GMCs proliferation and TGF-β1 expression, which may be independent of its hypoglycemic effect on preventing the development of mesangial cell fibrosis and closely related to the direct inhibition of SphK1 pathway.
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Animals , Rats , Lipopolysaccharides/pharmacology , Mesangial Cells , Resveratrol/pharmacology , Transcription Factor AP-1 , Transforming Growth Factor beta1 , Intercellular Signaling Peptides and Proteins , Cell Proliferation , DNA , Cells, CulturedABSTRACT
@#Sphingosine kinase 1 (SphK1) is an important protein that regulates the lipid microenvironment of cell membranes, and plays an important role in the dynamic equilibrium of ceramide, sphingosine and sphingosine-1-phosphate.The overexpression of SphK1 is closely related to the occurrence, development and migration of tumors as well as the generation of drug resistance.SphK1 inhibitors can induce apoptosis of various tumor cells and reverse drug resistance, which has a good prospect for drug development.In this article, the structural biology of SphK1, the structural types and structure-activity relationships of SphK1 inhibitors are reviewed.
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Objective To investigate the therapeutic effect of SPK1 gene transfected adipose derived mesenchymal stem cells(ADMSC)on experimental autoimmune encephalomyelitis mice and the effect on T helper cell 17(Th17)/regulatory T(Treg) cells balance. Methods EAE was induced by myelin oligodendrocyte glycoprotein 35-55 in mice.Totally 44 mice were randomly divided into four groups:normal control group(NC group),model group(EAE group),ADMSC group,and ADMSC-SPK1 group.Forty days after injection,the pathological changes of brain and spinal cord,Th17/Treg-related inflammatory markers in brain tissue,expressions of interleukin-17A(IL-17A)and forkhead box protein p3(Foxp3)in brain and spinal cord tissue,and flow cytometric results of spleen immune cells were detected. Results Forty days after the injection,serious inflammatory cell infiltration and demyelination occurred in the brain and spinal cord of EAE group,whereas demyelination and axonal injury were improved in ADMSC group and ADMSC-SPK1 group.Compared with EAE group,the ADMSC group and ADMSC-SPK1 group had significantly improved levels of IL-17A(
Subject(s)
Animals , Mice , Adipose Tissue/cytology , Cytokines , Encephalomyelitis, Autoimmune, Experimental/therapy , Interleukin-17 , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/cytology , Mice, Inbred C57BL , Phosphotransferases (Alcohol Group Acceptor)/genetics , T-Lymphocytes, Regulatory/cytology , Th17 Cells/cytology , TransfectionABSTRACT
Objective: To evaluate the inhibitory role of a novel oncolytic adenovirus (OA), GP73-SphK1sR-Ad5, on the growth of hepatocellular carcinoma (HCC). Methods: GP73-SphK1sR-Ad5 was constructed by integrating Golgi protein 73 (GP73) promoter and sphingosine kinase 1 (SphK1)-short hairpin RNA (shRNA) into adenovirus serotype 5 (Ad5), and transfecting into HCC Huh7 cells and normal human liver HL-7702 cells. The expression of SphK1 and adenovirus early region 1 (E1A) was detected by quantitative real-time PCR (qRT-PCR) and western blot, respectively. Cell viability was detected by methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay, and apoptotic rate was determined by flow cytometry. An Huh7 xenograft model was established in mice injected intratumorally with GP73-SphK1sR-Ad5. Twenty days after injection, the tumor volume and weight, and the survival time of the mice were recorded. The histopathological changes in tumor tissues were observed by hematoxylin-eosin (HE) staining and transmission electron microscopy (TEM). Results: Transfection of GP73-SphK1sR-Ad5 significantly upregulated E1A and downregulated SphK1 in Huh7 cells, but not in HL7702 cells. GP73-SphK1sR-Ad5 transfection significantly decreased the viability and increased the apoptotic rate of Huh7 cells, but had no effect on HL7702 cells. Intratumoral injection of GP73-SphK1sR-Ad5 into the Huh7 xenograft mouse model significantly decreased tumor volume and weight, and prolonged survival time. It also significantly decreased the tumor infiltration area and blood vessel density, and increased the percentages of cells with nucleus deformation and cells with condensed chromatin in tumor tissues. Conclusions: GP73-SphK1sR-Ad5 serves as a novel OA and can inhibit HCC progression with high specificity and efficacy.
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Objective To investigate the effect of moxifloxacin(MXF)on inflammatory reaction of mice abdominal peritoneal macrophage induced by LPS.Methods The level of TLR4、SPHK1 and NF-κB mRNA was determined by realtime-PCR;The relative levels of TLR4、SPHK1 and NF-κB were determined by Western blot.TNF-αand IL-1 se-creted by macrophages were detected by ELISA.Results At low and medium concentration(8,16 mg/L)of the MXF have inhibitory effect on the increasing of TLR 4,SPHK1,NF-κB expression level and cell supernatant of TNF-αand IL-1 in LPS stimulation of mice peritoneal macrophages.High concentration(64 mg/L)of the MXF promoted the role of inflammation.Conclusions The MXF of low and medium concentrations can inhibit the inflammatory response in LPS stimulation of mice peritoneal macrophages,and high concentration of the MXF showed contrary effects.
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@#[Abstract] Objective: To investigate the effect of sphingosine kinase 1 (SphK1) knockdown on the proliferation and migration of colon cancer RKO cells induced by mesenchymal stem cells (MSCs). Methods: RKO cells were treated with MSCs conditioned medium (MSC-CM) or control medium (Control-CM), respectively. Cell proliferation was detected by CCK-8 assay. Cell migration ability was tested by Transwell chamber assay. The proteins expression of Ki-67, MMP-2/9, CD44 and CD133 was detected by Western blotting. Then, the expression of SphK1 in RKO cells was suppressed by targeted gene lentivirus shRNA vector transfection. The effects of SphK1 knockdown on the proliferation, migration and protein expressions of Ki-67, MMP-2/9, CD44 and CD133 of RKO cells induced by MSC-CM were observed. Results: The RKO cells proliferation was promoted by MSC-CM in a time-dependent manner; moreover (P<0.05), the migration ability of cells was significantly enhanced after being treated with MSC-CM(P<0.01). In addition, MSC-CM significantly increased the protein expressions of Ki-67, MMP-2/9, CD44 and CD133(all P<0.05 or P<0.01). Lentiviral ShRNA vector transfection could significantly inhibit the expression of SphK1. Down-regulation of SphK1 significantly inhibited the proliferation, migration and protein expressions of Ki-67, MMP-2/9, CD44 and CD133 of RKO cells induced by MSC-CM(all P<0.05 or P<0.01). Conclusion: MSC-CM promotes the proliferation and migration of colon cancer RKO cells. Down-regulation of SphK1 reverses the cell proliferation and migration induced by MSC-CM via inhibiting the expression of MMP-2/9, CD44 and CD133.
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AIM: To observe the effects of miR-542-5p on the proliferation of rat small intestine crypt epithe-lial IEC-6 cells induced by sphingosine-1-phosphate (S1P).METHODS: Two IEC-6 cell lines (SphK1-IEC-C1 and SphK1-IEC-C2) were established, which expressed sphingosine kinase-1 (SphK1) stably.Radioactive tracer was used to detect SphK1 activity and S1P secretion.The cell proliferation was observed by cell counting and described by drawing growth curve, and the cell cycle analysis was carried out by flow cytometry.The level of miR-542-5p was evaluated by RT-qPCR.RESULTS: Compared with control vector cells without SphK1 cDNA, both SphK1-IEC-C1 and SphK1-IEC-C2 cell lines showed that Sphk1 was elevated, both intracellular and extracellular S1P increased dramatically, the rate of cell growth was faster, the percentage of the cells in S phase increased, and miR-542-5p expression decreased.S1P (0.5~10 μmol/L) led to the decrease in miR-542-5p expression.On the contrary, SphK1 silencing resulted in the increase in miR-542-5p expression in the IEC-6 cells.The miR-542-5p was elevated in SphK1-IEC-C1 cells and SphK1-IEC-C2 cells, which caused the decrease in the percentage of the cells in S phase.The cell growth rate in the above-mentioned 2 cell lines decreased compared with negative control group.CONCLUSION: In IEC-6 cells, S1P promotes proliferation by inhibiting miR-542-5p expression, which induces the cell cycle transferring from G1 phase to S phase.
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Objective To investigate the impact of sphingosine kinase 1 (SPK1) modified adipose tissue-derived stromal cells(ADSC)on tissue engineered bone osteogenesis.Methods ADSC cells isolated from SD rat fat cells were divided into CON group and SPK1 group,and then the cells were respectively infected with 10 MOI CON and SPK1 lentivirus for 48 h.The infection efficiency was confirmed by using flow cytometry.Alizarin red and oil red O was used to stain the cells 14 days after ADSC infection,and osteogenic and adipogenic ability was evaluated by detecting A595nm and A490 nm.In the meantime,the activity change of alkaline phosphatase(ALP)was detected.The SD rat femoral defect model was created,and then after combining ADSC with β-TCP,the tissue engineered bone was pressed to the defect site.The repairment of bone defect was detected by X-ray in 4,6 weeks.After infection of CON and SPK1 virus,bone morphogenetic protein(BMP7)expression in ADSC of these two groups was detected.Results The infection efficiency of CON and SPK1 lentivirus was 94.4％ vs.94.9％ respectively by flow cytometry.The SPK1 protein expression level in CON group and SPK1 group was (0.73±0.10) vs.(1.29±0.17)(P＜0.05).The A value of CON and SPK1 group at 595 nm was (0.20±0.02) vs.(0.41±0.01) (P＜0.05),respectively.The A value of CON and SPK1 group at 490 nm was (0.72±0.01) vs.(0.51±0.02)(P＜0.05),respectively.The expression level of ALP in CON and SPK1 group was (1.42±-0.09) vs.(2.68±0.09) (P＜0.01),respectively.In the repairment of bone defect,high density tissue at rat bone defect was significantly larger in SPK1 group than in CON group in 4 weeks,and in 6 weeks,bone defect of SPK1 group was healed,but CON group still had defect.The expression level of BMP7 in CON and SPK1 group was (1.13±0.16) vs.(4.46±0.23)(P＜0.05),respectively,48 h after infection.Conclusion SPK1 modified ADSC has an enhanced osteogenesis ability in vitro and in vivo,which was related to the activation of BMP7.
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Aim To investigate the effect of sphingo-sine kinase 1 (SphK1 )on unilateral ureteral obstruc-tion(UUO)-induced tubulointerstitial fibrosis and ex-plore the possible mechanism.Methods The CD-1 mice were randomly divided into four groups:sham-op-eration group(Sham),PF-543 treatment control group (Sham +PF-543),model group(UUO)and PF-543 treatment group(UUO +PF-543).On 1 ,3,7 and 1 4 d after operation,eight mice were selected randomly from each group and sacrificed.The protein expressions of SphK1 ,mature TGF-β1 ,FN,ColⅠ,LC3,Beclin1 ,Atg5 and Atg1 2 were observed by Western blot.The histo-logical changes were examined by Masson′s trichrome stain.Immunhistochemistry was performed to measure the levels of expression of SphK1 ,FN and Col Ⅰ. Transmission electron microscope was used to observe the autophagic body.Results SphK1 expression and autophagy were both upregulated in a mouse model of kidney fibrosis induced by UUO. Meanwhile, in-creased mature TGF-β1 and deposition of extracellular matrix(ECM)were observed in tubulointerstitial areas compared with sham-operated mice.After intraperito-neal injection with the SphK1 specific inhibitor PF-543 in UUO mice,enhanced expression of SphK1 and acti-vated autophagy were significantly abrogated.Howev-er,aggravation of renal fibrosis was detected when SphK1 inhibitor PF-543 was applied to suppress SphK1 expression in UUO mice.Conclusion SphK1 activa-tion is renoprotective through the induction of autoph-agy in the pathogenesis of kidney fibrosis.
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Objective To examine the role of SPHK-1/S1P and NFκB p65 signal pathway in non-small cell lung cancer (NSCLC)drug-resistant cells.Methods The drug-resistant cell line of lung cancer H460/DDP was constructed and its biological characteristics were identified successfully.The expression of SPHK-l was tested by RT-PCR and Western blot methods.S1 P and some proteins related to NFκB pathway were studied by Western blot. Results The drug-resistant lung cancer cell line H460/DDP was constructed and its drug-resistant ability was evaluated (IC50H460/DDP = 50.62μg/mL, RIH460/DDP = 2.95 ). Cisplatin at a concentration of 10 - 80 μg/mL significantly decreased cell death of drug-resistant cell line (P<0 .01 ).Western blot assay analysis showed that overexpressions of SPHK-l,S1 P and NFκB p65 were significantly higher in drug-resistant cell line than in their parent cell line H460 (P=0.0415,P=0.0465,P=0.0218).RT-PCR method revealed that SPHK-1 mRNA was overexpressed in drug-resistant cell line compared with that in their parent cell line H460 (P<0.05).More NFκB p65 protein in cell nucleus was expressed in drug-resistant cells than in parent cells.Conclusion SPHK-1/S1P and NFκB p65 signal pathway may play an improtant role in the drug-resistant H460 cell line in non-small cell lung cancer.
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[ ABSTRACT] AIM:To investigate the effects of sphingosine kinase l ( SphK1) and focal adhesion kinase ( FAK) on the epithelial-mesenchymal transition ( EMT) of human colon cancer HCT 116 cells.METHODS:Human colon cancer HCT116 cells were divided into 3 groups.N, N-dimethylsphingosine (DMS) was used to suppress the activity of SphK1. PF573228 was used to suppress the activation of FAK .The cells treated with equal volume of culture medium severed as control group.The cell viability was measured by MTT assay .The protein expression of SphK1, FAK and the EMT relative protein E-cadherin, N-cadherin, vimentin and matrix metalloproteinase (MMP) 2 was analyzed by Western blot.The mR-NA expression of SphK1, sphingosine-1-phosphate (S1P), FAK, E-cadherin and vimentin was detected by real-time PCR. The ability of tumor cell migration was measured by wound-healing assay.RESULTS:The cell viability of HCT116 cells was suppressed by DMS and PF 573228 in dose and time dependent manners .DMS significantly suppressed the expression of SphK1, FAK, N-cadherin, vimentin and MMP2, meanwhile enhanced the expression of E-cadherin.PF573228 reduced the expression of FAK , SphK1, N-cadherin, vimentin and MMP2, meanwhile increased the expression of E-cadherin (P<0.01).In addition, the migration ability of HCT116 cells was significantly decreased by treating with DMS and PF573228 (P<0.01).Compared with control group , the mRNA expression of FAK, SphK1, S1P and vimentin was de-creased, while the expression of E-cadherin was increased significantly in PF573228 group and DMS group (P<0.05). CONCLUSION:SphK1 and FAK signaling pathways may play an important role in the occurrence of EMT in the colon cancer HCT116 cells.
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BACKGROUND: The ojective of the following study is to investigate the role of sphingosine kinase 1 (Sphk1) in the malignant transformation of breast epithelial cells and breast cancer progression and its mechanism. MATERIALS AND METHODS: Immunohistochemistry was performed to detect Sphk1 and E‑cadherin (E‑cad) in resected breast samples. Sphk1 was transfected in normal human breast epithelial cell line (MCF‑10A) by Lentivirus and silenced in breast cancer cell line (MCF‑7) using small interfering ribonucleic acid. The effect of tumor necrosis factor alpha (TNF‑α) and/or N, N‑dimethylsphingosine (DMS) on the Sphk1 and E‑cad expression, MCF‑10A cell proliferation and invasion was investigated. Real time‑polymerase chain reaction and western‑blot was used to detect messenger ribonucleic acid and protein. Cell counting kit‑8 and transwell were used to measure cell proliferation and invasion. RESULTS: Sphk1 was positive expression in 114 breast tumors (75.50%) but negative in fibroadenomas. The expression of E‑cad and Sphk1 were negatively correlated and E‑cad (−)/Sphk1 (+) carriers showed higher ratio of axillary lymph node metastasis than E‑cad (+)/Sphk1 (−) carriers. Overexpression of Sphk1 in MCF‑10A reduced E‑cad expression and improved cell proliferation and invasion, but knockdown of Sphk1 in MCF‑7 decreased cell proliferation and invasion. TNF‑α increased Sphk1 expression, enhanced the ability of Sphk1 in decreasing E‑cad expression, which could be blocked by DMS. TNF‑α promoted MCF‑10A cell proliferation and invasion.CONCLUSION: Sphk1 plays an important role in the malignant transformation of breast epithelial cells and modulates breast cancer metastasis through the regulation of E‑cad expression. TNF‑α can up‑regulate Sphk1 expression and reduce E‑cad expression through Sphk1, which can be blocked by DMS. TNF‑α/Sphk1/E‑cad pathway may be a newly discovered pathway and plays an important role in tumorigenesis and metastasis.
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Objective To investigate expression level of sphingosine kinase 1 (SPHK1) and nuclear factor-κB (NF-κB) in non-small cell lung cancer (NSCLC) and their relationships with invasion, metastasis and prognosis of NSCLC. Meth-ods Ninety-three NSCLC specimens and paraneoplastic normal lung tissue from conventional surgery were confirmed by histology. Expression of SPHK1 and NF-κB were detected by Immunohistochemistry on paraffin sections. Primary antibody were Rabbit Anti-Human SPHK1 and Rabbit Anti-Human NF-κB p65, which were incubated 1 hour in water bath. The secondary antibody was HRP-Polymer anti Mouse IgG, which was incubated 20 minutes in water bath. Results SPHK1 ex-pression was positive in 96.8% (90/93) of NSCLC specimen which is higher than in paraneoplastic normal lung tissue in which the positive rate is 18.3%(17/93);NF-κB expression was positive in 89.2%(83/93) NSCLC which is higher than the in paraneoplastic normal lung tissue in which the positive rate is 12.9%(12/93). The expression of SPHK1 and NF-κB in NSCLC was positively correlated (r=0.464, P＜0.01). TThe expression levels of SPHK1 and NF-κB p65 in NSCLC patients with were positively related to TNM staging and lymph node metastasis. SPHK1 expression and NF-κB p65 expression lev-el were higher in the deads than in survivals. There was no statistical significance in different expression intensity of SPHK 1 and NF-κB p65 in patients with NSCLC who had differences in gender, age, tumor size, tumor location, histological type. Survival analysis showed that survival time of patients of NSCLC with high expression of SPHK1 was shorter than those in the group with low SPHK1 expression, and the difference was statistically significant (χ2=14.025, P ＜ 0.01). Conclusion In the process of NSCLC invasion and metastasis,SPHK1 may play an important role through NF-κB, and it can predict prognosis of NSCLC patient. Moreover, it will become a potential target for NSCLC target.
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Objective To investigate the effects of sphingosine kinase 1 (SphK1 ) inhibitor N, N-dimethylsphingosine (DMS)combined with 5-fluorouracil (5-FU)on the proliferation and apoptosis of gastric cancer MGC-803 cells and to explore the possible mechanisms involved.Methods MGC-803 cells were cultured in vitro.The effects of DMS and 5-FU on cell proliferation,apoptosis,and cell cycle distribution of MGC-803 cells were detected by MTT assay and flow cytometer (FCM),respectively.The expressions of SphK1 ,TS,DPD,NF-κB p65 and Bcl-2 proteins were detected by Western blot.Results Different concentrations of DMS or 5-FU alone or in combination could obviously inhibit the proliferation of MGC-803 cells in a dose-dependent and time-dependent manners (P0.05).As compared with the cells without drug treatment,DMS or 5-FU alone could obviously increase the apoptosis rate of MGC-803 cells (P<0.05);the apoptosis rate in the combination group was significantly higher than that in the single-drug groups (P<0.05).The expression levels of SphK1,NF-κB p65 and bcl-2 proteins were down-regulated with the treatment of DMS alone or in combination,whereas those of TS and DPD were not affected.Conclusion DMS can inhibit the proliferation and induce apoptosis of gastric cancer MGC-803 cells in vitro.It shows a good synergetic effect in combination with 5-FU,probably by down-regulating the expressions of SphK1,NF-κB p65 and Bcl-2 proteins.
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Objective To investigate the expression of sphingosine kinase 1(SphK1)and NF-κB in colon carcinoma tissues and their correlation with clinicopathologic features.Methods Sixty-six paraffinembedded colon carcinoma samples and 66 fresh colon carcinoma samples were tested using immunohistochemistry,RT-PCR and Western blot,respectively.Results In 66 fresh colon carcinoma samples,the positive rate of SphK1 and NF-κB mRNA expression were 84.85％(56/66)and 74.24％(49/66),while the positive rate of SphK1 and NF-κB protein detected by Western blot were 78.79％(52/66)and 69.70％(46/66).The positive rates were higher than those in the adjacent tissues[mRNA:63.64％(42/66),48.49％(32/66);protein:57.58％(38/66),45.45％(30/66)]and the normal mucosa [mRNA:42.42％(28/66),25.76％(17/66); protein:36.36％(24/66),24.24％(16/66)],with statistical significances(all P values ＜ 0.05).The mean expressive levels of SphK1 and NF-kB mRNA and protein in colon carcinoma were both significantly higher than those in the adjacent tissues and the normal mucosa(mRNA:0.55±0.06 vs0.35 ±0.05 vs0.25±0.05,0.75 ±0.06 vs0.43±0.05 vs0.30±0.04 ; protein:0.77 ± 0.05 vs 0.38 ± 0.06 vs 0.12 ± 0.03,0.45 ± 0.08 vs 0.23 ± 0.05 vs 0.13 ± 0.03 ;all P values ＜ 0.05).There was a close correlation between SphK1 and NF-kB expression levels (r =0.459,P =0.036).The results of immunohistochemistry were similar to those of RT-PCR and Western blot.Overexpression of SphK1 and NF-κB in colon carcinoma was related with depth of invasion,distant and lymph node metastasis and Dukes'stages(all P values ＜0.05).The expression of SphK1 was also related with differentiation(P ＜ 0.05).Conclusions Overexpression of SphK1 and NF-κB may be involved in the pathogenesis and progression of colon carcinoma.Moreover,SphK1 and NF-κB may be correlated with the invasion and metastasis of colon carcinoma.
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Objective To investigate the roles of sphingosine kinasel (SPK1) in apoptosis,invasiveness and multidrug resistance of human hepatocellular carcinoma cell line BEL-FU.Methods BEL-FU cells were infected with adenovirus carrying SPK1wT gene and SPK1siRNA (Ad-H1-SPK1) gene.Their effects on biological characteristics of BEL-FU cells were evaluated by MTT,cellular SPK enzyme activity assay,Transwell Migration Technology and Western-blot,respectively.Results AdSPK1wT significantly increased SPK activity but SPK1siRNA(Ad-H1-SPK1) decreased SPK activity.Over expression of SPK1 suppressed the apoptosis induced by DMS(Dimethyl sphingosine,DMS) and enhanced migration of BEL-FU cells.The cells infected with SPK1 siRNA( Ad-H1-SPK1)significantly increased the apoptosis induced by DMS and inhibited the migration of human hepatocellular carcinoma cells.The expression of multidrug resistance-related protein (MRP1) of cells infected with SPK1siRNA (Ad-H1-SPK1) was suppressed significantly compared with the control group,while the expression of MRP1 infected with Ad- SPK1wT was enhanced.Conclusion SPK1 activity is closely associated with apoptosis、migration and multidrug resistance of human hepatocellular carcinoma cells,therefore,it may serve as a new target for HCC treatment.