Down-regulation of histone deacetylase 7 reduces biological activities of retinal microvascular endothelial cells under high glucose condition and related mechanism

AIM:To investigate the expression and effect of histone deacetylase 7(HDAC7)in human retinal microvascular endothelial cells(HRMECs)under high glucose condition and related mechanism,and the expression of HDAC7 in the retinal tissue in diabetic rats.METHODS:The expression of HDAC7 in HRMECs under high glucose and the retinal tissue from normal or diabetic rats were detected with immunohistochemistry and Western blot.LV-shHDAC7 HRMECs were used to study the effect of HDAC7 on cell activities.Cell count kit-8(CCK-8),5-ethynyl2’-deoxyuridine(EdU),flow cytometry,scratch test,Transwell test and tube formation assay were used to examine the ability of cell proliferation,migration,and angiogenesis.Finally,a preliminary exploration of its mechanism was performed by Western blot.RESULTS:The expression of HDAC7 was both upregulated in retinal tissues of diabetic rats and high glucosetreated HRMECs.Down-regulation of HDAC7 expression significantly reduced the ability of proliferation,migration,and tube formation,and reversed the high glucose-induced high expression of CDK1/Cyclin B1 and vascular endothelial growth factor in high glucose-treated HRMECs.CONCLUSION:High glucose can up-regulate the expression of HDAC7 in HRMECs.Down-regulation of HDAC7 can inhibit HRMECs activities.HDAC7 is proposed to be involved in pathogenesis of diabetic retinopathy and a therapeutic target.

Study on regulating mechanisms of oxocrebanine obtained from Stephania hainanensis H.S.Lo et Y.Tsoong on microtubule sites and tubulin in human breast cancer MCF-7 cells

Objective:To determine the destructive ability of oxocrebanine,an anti-breast cancer active compound obtained from Stephania hainanensis H.S.Lo et Y.Tsoong,on microtubule network,and investigate the effect of oxocrebanine on microtubule network homeostasis at both molecular and cellular levels.Methods:the EBI site competition method and molecular docking method were used to determine the occupation of the microtubule site of oxocrebanine.Western Blot was used to detect the effect of oxocrebanine on microtubule-associated proteins including STAT3,PAK1,CAMK4,and PKA.Results:The results of EBI site competition assay showed that the binding of EBI toβ-Tubulin covalent fusions produced adducts that appeared in regions of lower molecular weight thanβ-tubulin(ctrl 2).Molecular docking results showed that oxocrebanine could occupy the colchicine site of microtubule proteins.As revealed by Western Blot,the expression of STAT3 protein was decreased after MCF-7 cells have been treated with low,medium,and high concentration of oxocrebanine or the positive drug taxol for 48 h(P<0.01).The expression levels of PAK1 and Camk4 proteins aslo showed significant reductions(P<0.05,or P<0.01).Oxocrebanine also decreased the PKA protein in MCF-7 cells compared to the control group(P<0.01).Conclusions:Oxocrebanine,a ligand that binds at the colchicine site of tubulin,perturbs tubulin polymerization and causes mitosis in MCF-7 cells,thus leading to MCF-7 cell death.Oxocrebanine may promote microtubule dynamics through stathmin by inhibiting the expression levels of STAT3,PAK1,Camk4,and PKA proteins in MCF-7 cells.Oxocrebanine interfers with spindle formation,and ultimately causes mitotic catastrophe in MCF-7 cells.

非剥脱点阵激光联合侧柏叶酊对斑秃小鼠IL-7/IL-7Rα信号通路和Tregs细胞亚群的影响

目的:研究1565 nm非剥脱点阵激光联合侧柏叶酊(Platycladus orientalis tincture,POT)对斑秃(Alopecia areata,AA)小鼠治疗作用以及对白细胞介素7(Interleukin 7,IL-7)/白细胞介素7受体α(Interleukin-7 receptorα,IL-7Rα)信号通路和调节性T细胞(Regulatory T cells,Tregs)亚群的影响。方法:将50只成年雄性C3H/HeJ小鼠随机分为对照组(C组),模型组[M组,环磷酰胺(Cyclophosphamide,CTX)诱导AA模型],M+1565 nm组(1565 nm非剥脱点阵激光治疗AA),M+POT组(POT治疗AA)、M+1565 nm+POT组(1565 nm非剥脱点阵激光联合POT治疗AA),每组10只。流式细胞术检测C组和M组皮损组织中Tregs细胞亚群的比例和所有组血液中单个核细胞中Tregs细胞亚群的比例。Western blot法检测各组小鼠皮损组织中IL-7和IL-7Rα的表达。结果:与C组比,M组皮肤组织IL-7和IL-7Rα的表达均明显增加,而且Tregs细胞比例明显减少(P<0.05)。与M组比,M+1565 nm组和M+POT组IL-7的表达均降低(P<0.05)。与M组比,M+1565 nm+POT组IL-7和IL-7Rα的表达均降低,且Tregs细胞比例都显著增加(P<0.05)。结论:1565 nm非剥脱点阵激光联合POT治疗可以抑制斑秃小鼠IL-7/IL-7Rα信号并减少Tregs细胞的比例。

DHCR7基因在胃癌中的表达及其与免疫相关基因的关系

目的探究7-脱氢胆固醇还原酶(DHCR7)基因在胃癌中的表达及其与免疫相关基因的关系。方法使用UALCAN、TIMER数据库分析DHCR7基因在不同类型肿瘤中的表达情况。使用GEPIA、TCGA、GEO数据库分析DHCR7基因在胃癌中的表达。Kaplan-Meier Plotter数据库分析DHCR7基因表达与胃癌患者预后的相关性。通过cBioPortal数据库找出与DHCR7共表达的基因,并展示这些基因中相关系数比较高的基因。对胃癌中与DHCR7表达正负相关的基因进行基因本体分析(GO)和京都基因与基因组百科全书(KEGG)分析,首先分析DHCR7基因与CD8^(+)T细胞以及招募CD8^(+)T细胞相关趋化因子的相关性;其次分析DHCR7基因与免疫激活相关基因的相关性;最后分析DHCR7表达与胃癌患者临床病理学特征的关联。结果DHCR7基因在大多数肿瘤类型中均有高表达趋势。DHCR7基因在胃癌中的表达高于正常胃黏膜。Kaplan-Meier Plotter数据库中201790-s-at芯片结果显示高表达DHCR7组患者生存期较短。与DHCR7负相关基因的GO、KEGG通路富集分析主要富集在免疫相关功能和信号通路上,DHCR7与CD8^(+)T细胞、招募CD8^(+)T细胞相关的趋化因子以及免疫激活基因都具有负相关性。DHCR7高表达与胃癌患者年龄呈正相关。结论DHCR7在胃癌组织中呈高表达,高表达DHCR7患者预后不良,DHCR7基因能够影响胃癌免疫微环境,有望成为胃癌免疫治疗的新靶点。

雷公藤内酯醇通过调控miR-142-3p/HSP70通路抑制人乳腺癌MCF-7细胞增殖、侵袭和迁移

目的:探究雷公藤内酯醇(TP)通过miR-142-3p/HSP70信号通路对人乳腺癌MCF-7细胞恶性生物学行为的影响。方法:常规培养MCF-7细胞,将其分为6组:对照组、TP组、miR-142-3p inhibitor组、TP+inhibitor组、miR-142-3p mimic组和TP+mimic组,用转染试剂将相应的核酸或质粒转染MCF-7细胞。qPCR法、EdU细胞增殖实验、Transwell小室实验、细胞划痕实验、WB法分别检测转染后各组MCF-7细胞中miR-142-3p和HSP70 mRNA的表达,MCF-7细胞的增殖、侵袭、迁移能力和HSP70蛋白表达水平。结果:TP或miR-142-3p过表达能显著促进MCF-7细胞中miR-142-3p和HSP70的表达,敲减miR-142-3p则可明显抑制MCF-7细胞中miR-142-3p和HSP70的表达,TP可逆转由敲减miR-142-3p对MCF-7细胞中miR-142-3p和HSP70表达的影响;TP、过表达miR-142-3p均可明显抑制MCF-7细胞的增殖、迁移和侵袭能力(均P<0.05),敲减miR-142-3p则均可促进MCF-7细胞的增殖、迁移和侵袭能力(均P<0.05),TP可逆转由敲减miR-142-3p对MCF-7细胞恶性生物学行为的影响(均P<0.05)。结论:TP可通过调控miR-142-3p/HSP70信号通路,进而抑制MCF-7细胞的增殖、侵袭和迁移能力。

USP7-MDM2-p53信号轴对子宫内膜癌细胞增殖、凋亡和细胞周期的影响

目的:探讨泛素特异性蛋白酶7(USP7)调节Mdm2 p53结合蛋白同源物(MDM2)-p53轴对子宫内膜癌细胞增殖、凋亡和细胞周期的影响。方法:Western blot检测人子宫内膜癌组织、癌旁组织、人子宫内膜上皮细胞hEEC及人子宫内膜癌细胞系Ishikawa、HEC-1-A、KLE中USP7蛋白表达。将Ishikawa细胞分为NC组、P22077(USP7抑制剂)组、pcDNA组、pcDNA-MDM2组、P22077+pcDNA组、P22077+pcDNA-MDM2组,CCK-8法和克隆形成实验检测Ishikawa细胞增殖;流式细胞术检测Ishikawa细胞凋亡与细胞周期变化;Western blot检测Ishikawa细胞中USP7、细胞周期蛋白D1(CyclinD1)、周期素依赖性激酶2(CDK2)、Bcl-2相关X蛋白(Bax)、MDM2、p53蛋白表达。以RG7388(MDM2抑制剂)或PFT-α(p53抑制剂)与20μmol/L P22077共处理Ishikawa细胞48 h以验证USP7-MDM2-p53信号轴上下游关系。结果:USP7蛋白在子宫内膜癌组织和细胞中高表达,且Ishikawa细胞中USP7蛋白表达量最高,因此,选择Ishikawa细胞为研究对象。与NC组比较,P22077组Ishikawa细胞OD 450值、克隆形成率、S期和G 2/M期细胞数、USP7、CyclinD1、CDK2、MDM2蛋白表达降低,细胞凋亡率、G_(0)/G_(1)期细胞数、p53、Bax蛋白表达升高(P<0.05);与NC组、pcDNA组比较,pcDNA-MDM2组Ishikawa细胞OD 450值、克隆形成率、S期和G 2/M期细胞数、USP7、CyclinD1、CDK2、MDM2蛋白表达升高,细胞凋亡率、G_(0)/G_(1)期细胞数、p53、Bax蛋白表达降低(P<0.05);与P22077组、P22077+pcDNA组比较,P22077+pcDNA-MDM2组Ishikawa细胞OD 450值、克隆形成率、S期和G 2/M期细胞数、USP7、CyclinD1、CDK2、MDM2蛋白表达升高,细胞凋亡率、G_(0)/G_(1)期细胞数、p53、Bax蛋白表达降低(P<0.05)。p53为USP7-MDM2通路下游分子。结论:抑制USP7表达可能通过下调MDM2来激活p53进而抑制Ishikawa细胞增殖、促进细胞凋亡及周期停滞。

Neuroprotective effects of neural stem cells pretreated with neuregulin1β on PC12 cells exposed to oxygen-glucose deprivation/reoxygenation

Studies on ischemia/reperfusion(I/R)injury suggest that exogenous neural stem cells(NSCs)are ideal candidates for stem cell therapy reperfusion injury.However,NSCs are difficult to obtain owing to ethical limitations.In addition,the survival,differentiation,and proliferation rates of transplanted exogenous NSCs are low,which limit their clinical application.Our previous study showed that neuregulin1β(NRG1β)alleviated cerebral I/R injury in rats.In this study,we aimed to induce human umbilical cord mesenchymal stem cells into NSCs and investigate the improvement effect and mechanism of NSCs pretreated with 10 nM NRG1βon PC12 cells injured by oxygen-glucose deprivation/reoxygenation(OGD/R).Our results found that 5 and 10 nM NRG1βpromoted the generation and proliferation of NSCs.Co-culture of NSCs and PC12 cells under condition of OGD/R showed that pretreatment of NSCs with NRG1βimproved the level of reactive oxygen species,malondialdehyde,glutathione,superoxide dismutase,nicotinamide adenine dinucleotide phosphate,and nuclear factor erythroid 2-related factor 2(Nrf2)and mitochondrial damage in injured PC12 cells;these indexes are related to ferroptosis.Research has reported that p53 and solute carrier family 7 member 11(SLC7A11)play vital roles in ferroptosis caused by cerebral I/R injury.Our data show that the expression of p53 was increased and the level of glutathione peroxidase 4(GPX4)was decreased after RNA interference-mediated knockdown of SLC7A11 in PC12 cells,but this change was alleviated after co-culturing NSCs with damaged PC12 cells.These findings suggest that NSCs pretreated with NRG1βexhibited neuroprotective effects on PC12 cells subjected to OGD/R through influencing the level of ferroptosis regulated by p53/SLC7A11/GPX4 pathway.

Hesperidin as a preventive resistance agent in MCF-7 breast cancer cells line resistance to doxorubicin

Objective:To evaluate of hesperidin to overcome resistance of doxorubicin in MCF-7 resistant doxorubicin cells(MCF-7/Dox)in cytotoxicity apoptosis and P-glycoprotein(Pgp)expression in combination with doxorubicin.Methods:The cytotoxic properties.50%inhibition concentration(IC_(50))and its combination with doxorubicin in MCF-7 cell lines resistant to doxorubicin(MCF-7/Dox)cells were determined using MTT assay.Apoptosis induction was examined by double staining assay using ethidium bromide-acridine orange.Immunocytochemistry assay was performed to determine the level and localization of Pgp.Results:Single treatment of hesperidin showed cytotoxic activity on MCF-7/Dox cells with IC_(50)value of 11μmol/L.Thus,combination treatment from hesperidin and doxorubicin showed addictive and antagonist effect(CI>1.0).Hesperidin did not increase the apoptotic induction,but decreased the Pgp expressions level when combined with doxorubicin in low concentration.Conclusions:Hesperidin has cytotoxic effect on MCF-7/Dox cells with IC_(50)of 11μmol/L.Hesperidin did not increased the apoptotic induction combined with doxorubicin.Cochemotherapy application of doxorubicin and hesperidin on MCF-7/Dox cells showed synergism effect through inhibition of Pgp expression.

Triterpenoid of avocado (Persea americana) seed and its cytotoxic activity toward breast MCF-7 and liver HepG2 cancer cells

Objective:To determine the structure of triterpenoid isolated from avocado seeds and the cytotoxic effect on MCF-7 and Hep G2 cells.Methods:The powder sample was macerated with ethanol,followed with separation of the extract by column chromatography.The target compound was monitored on thin layer chromatography plate and reagent Lieberman–Buchard.The isolated compound was characterized by spectral analysis,mainly ultraviolet,infrared,and liquid chromatographymass spectroscopy and their spectroscopic data with those reported in literature were compared.In vitro cytotoxic activity was investigated against Vero,MCF-7,and Hep G2 cell lines using MTT assay.Results:A triterpenoid compound was isolated from ethanol extract.The extracts,fraction(F3),and the isolated compound showed a significant cytotoxic activity against all investigated cell lines.MTT assay showed that the triterpenoid isolate inhibited cell proliferation of MCF-7 and Hep G2 cell line with the IC50 values of 62 mg/m L and 12 mg/m L,respectively,and was safe to normal cells.Conclusions:The results of the present study reveal that triterpenoid from avocado seeds have the potential for further development as anticancer agents.

Fucoidan Induces G_1 Phase Arrest and Apoptosis through Caspases-dependent Pathway and ROS Induction in Human Breast Cancer MCF-7 Cells

Fucoidan is an active component of seaweed, which inhibits proliferation and induces apoptosis of several tumor cells while the detailed mechanisms underlying this process are still not clear. In this study, the effect of Fucoidan on the proliferation and apoptosis of human breast cancer MCF-7 cells and the molecular mechanism of Fucoidan action were investigated. Viable cell number of MCF-7 cells was decreased by Fucoidan treatment in a dose-dependent manner as measured by MTT assay. Fucoidan treatment resulted in G1 phase arrest of MCF-7 cells as revealed by flow cytometry, which was associated with the decrease in the gene expression of cyclin D 1 and CDK-4. Annexin V/PI staining results showed that the number of apoptotic cells was associated with regulation of cytochrome C, cas- pase-8, Bax and Bcl-2 at transcriptional and translational levels. Both morphologic observation and Hoechst 33258 assay results confirmed the pro-apoptotic effect of Fucoidan. Meanwhile, the ROS pro- duction was also increased by Fucoidan treatment, which suggested that Fucoidan induced oxidative damage in MCF-7 cells. The results of present study demonstrated that Fucoidan could induce GI phase arrest and apoptosis in MCF-7 cells through regulating the cell cycle and apoptosis-related genes or proteins expression, and ROS generation is also involved in these processes.

8-bromo-7-methoxychrysin inhibits properties of liver cancer stem cells via downregulation of β-catenin

AIM:To evaluate whether 8-bromo-7-methoxychrysin(BrMC),a synthetic analogue of chrysin,inhibits the properties of cancer stem cells derived from the human liver cancer MHCC97 cell line and to determine the potential mechanisms.METHODS:CD133+cells were sorted from the MHCC97 cell line by magnetic activated cell sorting,and amplified in stem cell-conditioned medium to obtain the enriched CD133+sphere forming cells(SFCs).The stem cell properties of CD133+SFCs were validated by the tumorsphere formation assay in vitro and the xenograft nude mouse model in vivo,and termed liver cancer stem cells(LCSCs).The effects of BrMC on LCSCs in vitro were evaluated by MTT assay,tumorsphere formation assay and transwell chamber assay.The effects of BrMC on LCSCs in vivo were determined using a primary and secondary xenograft model in Balb/c-nu mice.Expressions of the stem cell markers,epithelialmesenchymal transition(EMT)markers andβ-catenin protein were analyzed by western blotting or immunohistochemical analysis.RESULTS:CD133+SFCs exhibited stem-like cell properties of tumorsphere formation and tumorigenesis capacity in contrast to the parental MHCC97 cells.We found that BrMC preferentially inhibited proliferation and self-renewal of LCSCs(P<0.05).Furthermore,BrMC significantly suppressed EMT and invasion of LCSCs.Moreover,BrMC could efficaciously eliminate LCSCs in vivo.Interestingly,we showed that BrMC decreased the expression ofβ-catenin in LCSCs.Silencing ofβ-catenin by small interfering RNA could synergize the inhibition of self-renewal of LCSCs induced by BrMC,while Wnt3a treatment antagonized the inhibitory effects of BrMC.CONCLUSION:BrMC can inhibit the functions and characteristics of LCSCs derived from the liver cancer MHCC97 cell line through downregulation ofβ-catenin expression.

Dietary Daidzein Enhances Antiapoptotic Effect of 17β-Estradiol (E_2) on Breast Cancer MCF-7 Cells

Objective： To investigate whether dietary daidzein interact with endogenous 17β-Estradiol （E2） to give rise to additive or inhibitory effects on proliferation and apoptosis in breast cancer cells. Methods： Cell cycle distribution and apoptosis induction were analyzed by using flow cytometry when breast cancer cell lines MCF-7 were cotreated with daidzein （1, 5 μmol/L） and E2 （0.1-10 nmol/L） for 5 days. Whether daidzein could alter E2-modulated mRNA expression of estrogen receptor alpha （ERα）, estrogen receptor beta （ERI3） and ERβ-estrogen response element （ERE） dependent transcription was investigated by RT-PCR and luciferase induction assays. The effects of daidzein on E2-modulated expression of proapoptotic p53, bax and antiapoptotic bcl-2 at both mRNA and protein levels were also investigated by RT-PCR and Western blot. Results： Daidzein enhanced the antiapoptotic effect in an Ea dose-dependent manner, but had no effect on E2-induced proliferation. Daidzein antagonized E2-induced ERβ mRNA expression and ERβ-ERE dependent transcription. In addition, daidzein only antagonized E2-upregulated expression of p53 and bax, but had no effect on E2-upregulated expression of bcl-2. Conclusion： Daidzein enhances the antiapoptotic effect of E2 on breast cancer cells by inhibiting E2-mediated p53-bax proapoptotic pathway. These results suggest that dietary daidzein may enhance deleterious effect of endogenous E2 in hormone-dependent breast cancer.

Cox7a2 mediates steroidogenesis in TM3 mouse Leydig cells

Aim： To investigate the regulatory function of Cox7a2 on steroidogenesis and the mechanism involved in TM3 mouse Leydig cells. Methods： The cDNA of Cox7a2 was cloned from TM3 mouse Leydig cells. It was subcloned to pDsRed- Express-N 1 and transfected back into TM3 mouse Leydig cells for Cox7a2 overexpression by transient gene transfection. Steroidogenesis affected by overexpressed Cox7a2 was studied by ELISA. To elicit the mechanism of this effect, expression of steroidogenic acute regulatory （STAR） protein and reactive oxygen species （ROS） were examined by Western blot and fluorometer, respectively. Results： The cDNA of Cox7a2 （249 bp） was cloned from Leydig cells and confirmed by DNA sequencing. After constructed pDsRed-Express-N1-Cox7a2 was transfected back into TM3 mouse Leydig cells, Cox7a2 inhibited not only luteinizing hormone （LH）-induced secretion of testosterone but also the expression of StAR protein. At the same time, Cox7a2 increased the activity of ROS in TM3 mouse Leydig cells. Conclusion： Cox7a2 inhibited LH-induced StAR protein expression, and consequent testosterone production, at least in part, by increasing ROS activity in TM3 mouse Leydig cells.

Roles of Smad3 and Smad7 in rat pancreatic stellate cells activated by transforming growth factor-beta 1

BACKGROUND: Pancreatic stellate cells (PSCs) play a major role in promoting pancreatic fibrosis. Transforming growth factor beta 1 (TGF-beta 1) is a critical mediator of this process. This study aimed to determine the expression of the Smad3 and Smad7 genes in the process of PSC activation, and explore the mechanisms of chronic pancreatitis. METHODS: The expressions of Smad3 and Smad7 in PSCs before and after TGF-beta 1 treatment were detected by reverse transcription-polymerase chain reaction and Western blotting analysis. Smad3 expression was detected in PSCs after treatment with 5 ng/ml of TGF-beta 1 for 24 hours. RESULTS: Smad7 expression was decreased in TGF-beta 1 -activated PSCs (P<0.05) in a dose-dependent manner. When TGF-beta 1 concentration reached 10 ng/ml, the expression of p-Smad3, Smad3, and Smad7 was inhibited (P<0.05). CONCLUSIONS: TGF-beta 1 promotes the expression of Smad3 and inhibits the expression of Smad7 during the activation of PSCs. In contrast, high-dose TGF-beta 1 downregulates the expression of Smad3 in completely activated PSCs.

Semaphorin 7A promotes human vascular smooth muscle cell proliferation and migration through theβ-catenin signaling pathway

Background:Vascular smooth muscle cells(VSMCs)undergo a conversion from a contractile phenotype to a proliferative synthetic phenotype,contributing to the pathogenesis of cardiovascular diseases.Semaphorin 7A(SEMA7A)is a glycosylphosphatidylinositol-anchored membrane protein that plays an important role in vascular homeostasis by regulating endothelial cell behaviors.However,the expression and role of SEMA7A in VSMCs remain unclear.Methods:In this study,we screened for VSMC-regulating genes in publicly available datasets and analyzed the expression of SEMA7A in human coronary artery smooth muscle cells(hCASMCs)treated with platelet-derived growth factor-BB(PDGF-BB).The effects of SEMA7A overexpression and knockdown on hCASMC proliferation and migration were examined.The signaling pathways involved in the action of SEMA7A in hCASMCs were determined.Results:Bioinformatic analysis showed that SEMA7A was significantly dysregulated in VSMCs treated with oxidized low-density lipoprotein or overexpressing progerin,a pro-atherogenic gene.The PDGF-BB stimulation led to a concentration-and time-dependent induction of SEMA7A.Depletion of SEMA7A attenuated PDGF-BB-induced hCASMC proliferation and migration.Conversely,overexpression of SEMA7A enhanced hCASMC proliferation and migration.Mechanistically,SEMA7A stimulated the activation of theβ-catenin pathway and upregulated c-Myc,CCND1,and MMP7.Knockdown ofβ-catenin impaired SEMA7A-induced hCASMC proliferation and migration.Conclusions:SEMA7A triggers phenotype switching in VSMCs through theβ-catenin signaling pathway and may serve as a potential therapeutic target for cardiovascular diseases.

EFFECT OF CIS-9, TRANS-11-CONJUGATED LINOLEIC ACID ON CELL CYCLE OF MAMMARY ADENOCARCINOMA CELLS(MCF-7)

Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B1, D1, p16ink4a and p21cip/waf1 of MCF-7 cells at various c9,t11-CLA concentrations (25μM, 50μM, 100μM and 200μM), at 24h and 48h. 96% ethand was used as negative control. Results: The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9,t11-CLA. After treatment with various doses of c9,t11-CLA mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively. Inhibitory effect of c9,t11-CLA on DNA synthesis (except for 25μM, 24h) was demonstrated by significantly less incorporation of 3H-TdR than the negative control (P<0.05 and P<0.01). To further investigate the influence of the cell cycle progression, we found that c9,t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that incubation with different concentration of c9,t11-CLA at various times significantly decreased the expression of PCNA, Cyclin A, B1, D1 in MCF-7 cells compared to the negative control (P<0.01), whereas the expression of p16ink4a and p21cip/waf1, cyclin-dependent kinases inhibitors (CDKI), were increased. Conclusions: The cell growth and proliferation of MCF-7 cells is inhibited by c9,t11-CLA via blocking cell cycle, accompanying reduced expression of cyclin A, B1, D1 and enhanced expression of CDKI (p16ink4a and p21cip/waf1).

基于网络药理学探讨山奈酚-7-O-新橘皮糖苷抗前列腺癌的作用机制

目的 探讨山奈酚-7-O-新橘皮糖苷(kaempferol-7-O-neohesperidoside, K7ON)抗前列腺癌细胞(prostate cancer, PCa)的作用及潜在分子机制。方法 采用CCK-8法检测K7ON对PCa细胞PC3、DU145、C4-2和LNCap增殖的影响;应用细胞划痕实验检测K7ON对DU145细胞迁移能力的影响;SuperPred等数据库获取K7ON和PCa的靶点;从Venny在线平台获取K7ON与PCa的共同靶点,应用String和Cytoscape构建蛋白相互作用(protein-protein interaction, PPI)网络;通过DAVID数据库进行GO和KEGG功能富集分析,构建“药物-靶点-疾病-通路”网络模型。通过流式细胞术检测K7ON对PCa细胞周期的影响;采用Western blot法检测周期相关蛋白Skp2、p27和p21蛋白的表达;应用Sybyl X2.0将Skp2与K7ON进行分子对接。结果 K7ON可显著抑制PCa细胞的增殖和迁移能力。筛选出药物与疾病的交集靶点共34个,其中Skp2、p27等是K7ON治疗PCa的关键靶点,进一步的GO和KEGG功能功能富集表明其机制主要与细胞周期相关。流式细胞术结果表明,K7ON处理可使DU145细胞周期阻滞在S期。与对照组相比,Skp2蛋白表达水平明显下调,p27和p21的蛋白表达水平上调。分子对接结果显示K7ON与受体Skp2具有较好的结合能力。结论 K7ON可抑制PCa细胞的增殖和迁移,使细胞周期阻滞在S期,其机制可能与调控Skp2-p27/p21信号通路相关。

Dodecylamine Derivative of Hydroxocobalamin Acts as a Potent Inhibitor of Cobalamin-Dependent Methionine Synthase in Mammalian Cultured COS-7 Cells

We evaluated whether the dodecylamine derivative of hydroxocobalamin acts as a potent inhibitor of cobalamin-dependent enzymes in an African green monkey kidney cell, COS-7. When the dodecylamine derivative (1.0 μmol/L) did not show any cytotoxicity in the cultured cells, the derivative could not affect methylmalonyl-CoA mutase (holo-enzyme) activity, but significantly inhibit methionine synthase (holo-enzyme) activity in the cell homogenates of COS-7 grown in 1.0 μmol/L hydroxocobalamin-supplemented medium. An immunoblot analysis indicated that the dodecylamine derivative could not decrease the protein level of methionine synthase, but significantly inhibit the enzyme activity.

Contralateral C7 transfer combined with acellular nerve allografts seeded with differentiated adipose stem cells for repairing upper brachial plexus injury in rats

Nerve grafting has always been necessary when the contralateral C7 nerve root is transferred to treat brachial plexus injury. Acellular nerve allograft is a promising alternative for the treatment of nerve defects, and results were improved by grafts laden with differentiated adipose stem cells. However, use of these tissue-engineered nerve grafts has not been reported for the treatment of brachial plexus injury. The aim of the present study was to evaluate the outcome of acellular nerve allografts seeded with differentiated adipose stem cells to improve nerve regeneration in a rat model in which the contralateral C7 nerve was transferred to repair an upper brachial plexus injury. Differentiated adipose stem cells were obtained from Sprague-Dawley rats and transdifferentiated into a Schwann cell-like phenotype. Acellular nerve allografts were prepared from 15-mm bilateral sections of rat sciatic nerves. Rats were randomly divided into three groups: acellular nerve allograft, acellular nerve allograft + differentiated adipose stem cells, and autograft. The upper brachial plexus injury model was established by traction applied away from the intervertebral foramen with micro-hemostat forceps. Acellular nerve allografts with or without seeded cells were used to bridge the gap between the contralateral C7 nerve root and C5–6 nerve. Histological staining, electrophysiology, and neurological function tests were used to evaluate the effect of nerve repair 16 weeks after surgery. Results showed that the onset of discernible functional recovery occurred earlier in the autograft group first, followed by the acellular nerve allograft + differentiated adipose stem cells group, and then the acellular nerve allograft group;moreover, there was a significant difference between autograft and acellular nerve allograft groups. Compared with the acellular nerve allograft group, compound muscle action potential, motor conduction velocity, positivity for neurofilament and S100, diameter of regenerating axons, myelin sheath thickness, and density of myelinated fibers were remarkably increased in autograft and acellular nerve allograft + differentiated adipose stem cells groups. These findings confirm that acellular nerve allografts seeded with differentiated adipose stem cells effectively promoted nerve repair after brachial plexus injuries, and the effect was better than that of acellular nerve repair alone. This study was approved by the Animal Ethics Committee of the First Affiliated Hospital of Sun Yat-sen University of China(approval No. 2016-150) in June 2016.

GB7 acetate,a galbulimima alkaloid from Galbulimima belgraveana,possesses anticancer effects in colorectal cancer cells

GB7 acetate is a galbulimima alkaloid obtained from Galbulimima belgraveana.However,information regarding its structure,biological activities,and related mechanisms is not entirely available.A series of spectroscopic analyses,structural degradation,interconversion,and crystallography were performed to identify the structure of GB7 acetate.The MTT assay was applied to measure cell proliferation on human colorectal cancer HCT 116 cells.The expressions of the related proteins were measured by Western blotting.Transmission electron microscopy(TEM),acridine orange(AO)and monodansylcadaverine(MDC)staining were used to detect the presence of autophagic vesicles and autolysosomes.A transwell assay was performed to demonstrate metastatic capabilities.Oxygen consumption rate(OCR)and extracellular acidification rate(ECAR)assays were performed to determine the mitochondrial oxidative phosphorylation(OXPHOS)and glycolysis activity of HCT 116 cells.The data showed that GB7 acetate suppressed the proliferation and colony-forming ability of HCT 116 cells.Pretreatment with GB7 acetate significantly induced the formation of autophagic vesicles and autolysosomes.GB7 acetate upregulated the expressions of LC3 and Thr172 phosphorylated adenosine 5'-monophosphate(AMP)-activated protein kinase a(p-AMPKa),which are key elements of autophagy.In addition,GB7 acetate suppressed the metastatic capabilities of HCT 116 cells.Additionally,the production of matrix metallo-proteinase-2(MMP-2)and MMP-9 was reduced,whereas the expression of E-cadherin(E-cad)was upregulated.Furthermore,GB7 acetate significantly reduced mitochondrial OXPHOS and glycolysis.In conclusion,the structure of the novel Galbulimima alkaloid GB7 acetate was identified.GB7 acetate was shown to have anti-proliferative,pro-autophagic,anti-metastatic,and anti-metabolite capabilities in HCT 116 cells.This study might provide new insights into cancer treatment efficacy and cancer chemoprevention.