Resveratrol Inhibits the Secretion of Vascular Endothelial Growth Factor and Subsequent Proliferation in Human Leukemia U937 Cells

This study examined the effect of resveratrol on the secretion of vascular endothelial growth factor(VEGF) and subsequent proliferation of human leukemia U937 cells,and explored the mechanisms involved.Human leukemia U937 cells were treated with resveratrol of different concentrations(12.5-200 μmol/L) for different time lengths(12-48 h).The proliferation of the U937 leukemic cells was determined by MTT assay.Apoptosis was observed by Annexin-Ⅴ-FIFC/PI double staining and flow cytometry(FCM).Cells cycle was analyzed by PI staining and FCM.The content of VEGF was determined by ELISA.Human umbibical vein endothelial cells were examined for vasoformation in vitro after exposures to resveratrol of various concetrations.The results showed that resveratrol inhibited the proliferation of U937 leukemia cells in a dose-and time-dependent manner.Resveratrol induced apoptosis and S-phase cell cycle arrest in human leukemic U937 cells.Resveratrol inhibited the secretion of VEGF in U937 cells.Resveratrol inhibited the vasoformation of human vein endothelial cells in a dose-dependent manner.It was concluded that resveratrol could down-regulate the secretion of VEGF,induce apoptosis and suppress the proliferation of U937 cells.     

Study of apoptosis induced by nordihydroguaiaretic acid in human ma-lignant glioma cell line SHG-44

Objective: To investigate the effect and mechanism of nordihydroguaiaretic acid (NDGA) on apop-tosis in human malignant glioma cell line SHG-44. Methods: Cell growth inhibition was measured with MTT assay. Cell apoptosis was observed with light and electron microscopy and TUNEL. Expression of bcl-2 gene was measured with immunohistochemistry, in situ hybridization and image analyses. Results: NDGA at the concentration of 100 μmol/L inhibited the proliferation of SHG-44 cells and induced apoptosis in a time-de-pendent manner. The expression of Bcl-2 protein in SHG-44 cells was decreased in the present of 100 μmol/L NDGA along with the duration of treatment in a negative correlation with the degree of cell apoptosis. The bcl-2 mRNA expressed in SHG-44 cells was reduced after treatment with 100 μmol/L NDGA, apparently consistent with the immunohistochemical results. Conclusion.- NDGA can induce apoptosis of human malig-nant glioma cells probably by down-regulating expression of bcl-2 gene, though the exact mechanism needs further study.     

Tumor Necrosis Factor-related Apoptosis Ligand Induces Apoptosis in Prostate Cancer PC-3M Cell Line

Summary： To study the effect of tumor necrosis factor-related apoptosis inducing ligand （TRAIL） on PC-3M cell line, PC-3M cell line was incubated with gradient concentrations of TRAIL for 4-24 h. Annixin-V fluorescence staining and TUNEL method were employed to detect the apoptosis of PC-3M cells. The morphology of apoptotic PC-3M cells was observed by electron microscopy. The relationship between TRAIL concentrations and the percentage of apoptotic cells was evaluated by flow cytometry. The proliferation inhibitory ratio was calculated by using MTT colorimetry. Our results showed that apoptosis of PC-3M cells could be induced by treatment with TRAIL for at most 4 h. The results of flow cytometry and MTT colorimetry demonstrated a time-and concentration-dependent relationship between cell apoptosis rate and TRAIL concentration. It is concluded that apoptosis of PC-3M cells can be induced by TRAIL. Because of the selective killing effect of TRAIL on tumor cells, it may become a potential alternative for the treatment of advanced prostate cancer.     

Experimental Studies on Cyclooxygenase-2 Inhibitor Induced Cervical Cancer Hela Cell Apoptosis and Its Molecular Mechanism

Objective To investigate the Hela cells growth inhibition and apoptosis possible molecular mechanisms. Methods Hela cells were treated with various concentrations (100 μmol/L,200 μmol/L, 300 μmol/L,400 μmol/L) of NS-398 (selective for COX-2 inhibition). Cell growth was measured by MTT (Thiazolyl blue). Apoptosis was detected by double staining flow cytometry (FCM). Levels of PGE2 were measured by radioimmunoassay. The expres- sions of COX-2 protein were also examined by Western blot analysis. Results After treated with different concentrations of NS-398, the growth of Hela cells was suppressed significantly in a dose-and time-dependent manner (P<0.01). The NS-398 can induce apoptosis with the apoptosis rates at 8.53%-43.46% by FCM in a dose-dependent manner. The release of PGE2 was reduced in Hela cells with the values of 69.26 ± 2.13, 47.46 ± 2.18, 28.15 ± 1.64 and 17.01 ± 1.12, respectively, there was significant difference compared with control group (83.78 ± 1.11) (P<0.01). The NS-398 could inhibit the activity and expression of COX-2 in a dose- dependent manner and down-regulated the expression of COX-2 protein greatly. Conclusion NS-398 could inhibit the proliferation and increase apoptosis in human Hela cells. These effects may be depended on the inhibition of the expression of COX-2 and PGE2 by NS-398.     

Role of Extracelluar Regulated Protein Kinases in FTY720-induced Apoptosis of Leukemia Cell Lines HL-60 and U937

The effects of a novel immunosuppressive agent FTY720 on proliferation inhibition and apoptosis of acute leukemia cell lines HL-60 and U937, and the role of extracelluar regulated protein kinase (ERK) in the course of proliferation inhibition and apoptosis induced by FTY720 were studied. The proliferation inhibition rate of HL-60 and U937 cells by various concentrations of FTY720 was detected by MTT assay. Cell apoptosis was detected by DNA fragmem analysis and flow cytometry. The phosphorylated ERK1/2 protein expression was observed by Western blotting. The change of intracellular distribution of ERK1/2 protein was identified by SP immunohistochemical staining. The results showed that FTY720 could inhibit the growth of HL-60 and U937cells effectively in a dose-dependent manner. After incubation with FTY720 for 24 h, apoptosis wasobserved in HL-60 and U937 cells. The intracellular expression of phosphorylated ERK1/2 protein was also down-regulated and the distribution of ERK1/2 protein in cell‘ nuclear was reduced during FTY720-induced apoptosis. So, that FTY720 inhibited ERK1/2 phosphorylation might mediate the role of FTY720-induced apoptosis and proliferation inhibition of leukemia cells.     

Effects of taurine on proliferation and apoptosis of hepatic stellate cells in vitro

BACKGROUND: Hepatic fibrosis, a common response to chronic liver injury, is characterized by increased production of extracellular matrix components, whose major part is produced by hepatic stellate cells (HSCs). Taurine is a sulfur containing beta-amino acid rich in human body, and our previous experiments showed that it can inhibit the deposition of the extracellular matrix in the damaged liver. This work was to investigate the effects of taurine on proliferation and apoptosis of HSC and its possible mechanism. METHODS.. Cell proliferation was detected by the thiazole blue (MTT) colorimetric assay. Cell apoptosis and cell cycle were assessed via flow cytometry. The morphology of apoptotic cells was observed by phase-contrast fluorescent micrography after orange acridine staining,     

Effect of Quercetin on Proliferation and Apoptosis of Human Nasopharyngeal Carcinoma HEN1 Cells

The effect of quercetin （Que） on proliferation and apoptosis of human nasopharyngeal carcinoma HEN1 cells was investigated. Inhibition rate of quercetin on HEN1 was assayed by MTT method, apoptosis by flow cytometry （FCM）, and the caspase-3 expression of each group by colorimetry set respectively. Quercetin inhibited HEN1 cells in in a dose-（r=0.709, P〈0.01） and time-dependent manner （r=0.703, P〈0.01）. The ratio of apoptotic and necrosis cells was increased in the cells treated with quercetin. Cell cycle was specificly arrested in G2/M phase. Apoptosis cusp was revealed by FCM. The activity of caspase-3 was significantly up-regulated in 5 groups treated with quecetin as compared with control group （P〈0.05）. It was concluded that the growth inhibition of quercetin was highly related to cell cycle arrest at the G2/M phase and induction of caspase-dependent apoptosis in human nasopharyngeal carcinoma HEN 1 cells.     

Effects of ATRA, Acitretin and Tazarotene on Growth and Apoptosis of Tca8113 Cells

Summary：To investigate the effects of ATRA, acitretin and tazarotene on the growth and apoptosis of human tongue squamous cell carcinoma cell line Tca8113. The effect of retinoids on growth of Tca8113 cells in vitro was examined by MTT assay and Trypan blue exclusion assay. Cell cycle analysis, early apoptosis analysis with double staining with Annexin V-FITC and PI, and active caspase-3 analysis with the staining of FITC-conjugated monoclonal rabbit anli-active caspase-3 antibody were made by flow cytometer. Streptavidin-biotin complex （SABC） immunocytochemical assays were employed for the detections of Bax/Bcl-2 proteins expressions. Our results showed that the retinoids inhibited growth of Tca8113 cells in a dose-and time-dependent manner with maximal inhibition 24 h after treatment of 10 5 mol/L. 10^-5 mol/L retinoids altered cell cycle distribution of Tca8113 cells, revealing an increase in G0/G1-phase population, a decrease in S-phase population and the inhibition of G1/S switching. 10^-5 mol/L retinoids significantly induced apoptosis of Tca8113 cells （all P〈0.05）, elevated the cells population with detectable active caspase-3 （P〈 0.05 for all）, increased the number of cells forming Bax and decreased the number of cells forming Bcl-2 significantly （all P〈0.05）. Acitretin played a most prominent role among the retinoids. It is concluded that the inhibition of cell cycle progress of Tca8113 cells by ATRA, acitretin and tazarotene is one of the possible mechanisms for proliferation arrest of TcaS113 cells elicited by the retinoids. The retinoids mediate apoptosis in TcaS113 cells that may be caspase-dependent through mitochondria pathway. High concentration retinoids inhibit growth of Tca8113 cells in vitro by interfering with proliferation and inducing apoptosis of cells. Acitretin may be an alternative medicine for the prevention and treatment of tongue squamous cell carcinoma.     

Altered gene expression reveals molecular mechanisms underlying oridonin-induced apoptosis of multiple myeloma LP-1 cells

Objective: To investigate the effect of oridonin on proliferation and invasion of human multiple myeloma LP-1 cells and the underlying mechanism. Methods: LP-1 cells in culture medium in vitro were treated with oridonin at the different concentration. Cell proliferation was measured by Microwave Theory and Techniques (MTT) assay and cell apoptotic rate was detected by flow cytometry. Morphology of cell apoptosis was observed by transmission electron microscope. Expressions of Bax, Bcl-2, Caspase-3, NF-κB as well as I-κB mRNA were detected by real-time PCR. Results: The MTT assays and flow cytometry revealed that oridonin could inhibit the growth of LP-1 cells and cause apoptosis significantly; the suppression was both in time- and dose-dependent manner. Marked morphological changes of cell apoptosis were found under a transmission electron microscope after the cells were treated with oridonin at 25 μmol/L for 24 h. Along with the apoptotic process, Bcl-2, Caspase-3,NF-κB gene expressions were down-regulated (P<0.05). On the contrast, the Bax and I-κB gene expressions were up-regulated (P<0.05). Conclusion: Oridonin could inhibit the proliferation of LP-1 cells via inducing apoptosis. We concluded that oridonin induces apoptosis in LP-1 cells via activation of caspase-3 as well as down-regulation of Bcl-2 and up-regulation of Bax expression. The results suggested that oridonin could induce apoptosis of LP-1 cells through mitochondria- and caspase3-dependent pathways. Meanwhile, the inhibition of NF-κB and the activation of I-κB indicate pro-apoptotic stimuli. In one word, oridonin might be an important potential anti-myeloma reagent.     

Effects of POH in Combination with STI571 on the Proliferation and Apoptosis of K562 Cells

Sofar ,the 2 phenylaminopyrimidineSTI5 71isthemostsuccessfulofthemolecularlydesignedATPcompetitorsfromNovartisPharma (Basel,Switzer land) ,whichspecificallyinhibitsAbltyrosinekinaseatmicromolarconcentrations .InhibitionoftheBcr Ablkinaseactivitybythiscom…     

HDAC1 expression and effect of curcumin on proliferation of Raji cells

Summary Histone deacetylase (HDAC₁) has a high expression in many cancer cells and curcumin can inhibit the growth of cancer cells. This paper was designed to investigate the expression of HDAC₁ of Raji cells and the effect of curcumin on their proliferation and apoptosis. Raji cells were treated with 3. 125–50 μmol/L curcumin for 8–48 h and the growth inhibition rates of Raji cells were measured by MTT. The expression of HDAC₁ on Raji cells were examined by mRNA, Western blot at 24 h various concertrations (1.6–50 μmol/L). Curcumin could selectively inhibit the proliferation of Raji cells in a dose and time dependent manner, with the inhibition rate being 52.47%–82.18% (P<0.01). The up-regulation of HDAC₁ expression was observed within 24 h after the treatment with curcumin as shown by RT-PCR and Western blot. With the increase of concentration, the expression was down-regulated in a dose dependent manner. It is concluded that the expression of HDAC₁ plays an important role in the proliferation and apoptosis of Raji cells and curcumin can inhibit the growth of Raji cells at various concentrations and promote the apoptosis of Raji cells. WU Qing, female, born in 1970, M. D., Ph. D. This project was supported by a grant from the National Natural Sciences Foundation of China (No. 30271672).     

Effect of Smac on TRAIL-induced apoptosis of prostate cancer cell line PC-3 and the molecular mechanism

The effect of Smac gene on the TRAIL-induced apoptosis of the prostate cancer cell line PC-3 and the molecular mechanism were investigated. The Smac gene was transfected into PC-3 cells under the induction of liposome. The intrinsic Smac gene expression was detected by Western blotting. After treatment with TRAIL as an apoptosis inducer, in vitro cell growth activity was as-sayed by MTT colorimetry. The apoptosis rate of PC-3 cells was determined by annexin Ⅴ-FITC and propidium iodide staining flow cytometry. The expression of cellular XIAP and caspase-3 genes was examined by Western blotting. Smac-transfected cells (PC-3/Smac group) had significantly in-creased Smac protein level as compared with PC-3 controls (P<0.01). After induction with 100-200 ng/mL TRAIL for 12-36 h, cellular proliferation rate in PC-3/Smac group was significantly lower than in PC-3 controls (P<0.05). After induction with 100 ng/mL TRAIL for 24 h, the apoptosis rate in PC-3/Smac group was significantly enhanced as compared with that of PC-3 controls (P<0.05). Ac-cordingly, the XIAP expression level was down-regulated significantly (P<0.05) and caspase-3 sub-unit P20 was up-regulated significantly (P<0.05). It is suggested that the over-expression of cellular Smac can inhibit inhibitor of apoptosis proteins (IAPs), enhance caspases activity and the apoptosis rate of PC-3 cells induced by TRAIL, which may provide a useful experimental basis for prostate cancer therapy.     

三氧化二砷对前列腺癌细胞PC-3凋亡抑制蛋白XIAP表达的影响

[目的]探讨三氧化二砷(As2O3)对前列腺癌细胞株PC-3细胞增殖、细胞凋亡及X染色体连锁凋亡抑制蛋白(XIAP)表达的影响.[方法]取对数生长期PC-3细胞,分别经0.5,1.0,2.0μmol/L As2O3处理,采用四甲基偶氮唑蓝比色法检测细胞生长抑制作用;流式细胞仪检测细胞凋亡率;蛋白质印迹法及实时荧光定量PCR检测XIAP蛋白表达及XIAP mRNA表达的变化.[结果]0.5,1.0,2.0μmol/LAs2O3均可抑制PC-3细胞增殖,在处理24,48,72h后,细胞生长抑制率间差异具有统计学意义(P<0.01).检测0.5,1.0,2.0μmol/L As2O3处理48h的PC-3细胞株细胞凋亡率分别为11.47%±1.81%,38.47%±1.60%,58.93%±3.35%,相比较差异具有统计学意义(P<0.01).As2O3处理48h时0.5,1.0,2.0μmol/L As2O3组的XIAP mRNA表达水平分别为0.67±0.12,0.25±0.15,0.03±0.01,各组间差异均具有统计学意义(P<0.05).[结论]As2O3可抑制PC-3细胞增殖,诱导细胞凋亡,此作用可能与As2O3抑制PC-3细胞XIAP基因的表达有关联.     

Growth inhibition and apoptosis inducing mechanisms of curcumin on human ovarian cancer cell line A2780

Curcumin,aphenolicpigmentextractedfrom curcuma,isthemajoreffectivecomponentofthat traditionalChinesemedicineandusedasadietarycoloringagentandanaturalcondiment.Recentre searchreportshaveshownthatcurcumincouldse lectivelyinhibittheproliferationandinducetheap optosisofmanytumorcells,buttheinvolvedmech anismsstillunclear(1,2).Thephenomenonthatcurcu mininducesapoptosisoftumorcellscouldbeseen innumerouscancers,however,theeffectsofcurcu minonhumanovariancancercellshavenotbeenre portedyet.Inthisresear…     

The anti-proliferative effect of inhibitor of telomerase on cultured retinal pigment epithelial cells

Proliferative vitreoretinopathy (PVR) has ahigh rate of inducing blind and isone of the commonreasons for rhegematogenous retinal detachmentsurgery falling.If PVR recurred after vitrectomy,the secondary operation will be more difficult,thecurative effect decreased,even induce blind finally.The pathologic process of PVR is:followingrhegematogenous retinal detachment,the blood- reti-nal barrier was break,glial cells,retinal pigment ep-ithelial(RPE) cells,fibroblastcells and macrophagesmove t…     

Growth-inhibitory Effects of Curcumin on Ovary Cancer Cells and Its Mechanisms

Sinceanti carcinogenicagentsalsobringabouttheapoptosisinnormalcellswhiletheyinduceapop tosisinneoplasmcells ,inrecent years ,efforthasbeendirectedatlookingforneweffectiveanti cancerdrugswithlowtoxicity .Curcuministhemajoractivecomponentofcurcuma ,whichisa…     

Inhibitory Effect of Curcumin on Proliferation of Human Pterygium Fibroblasts

In order to investigate the effect of curcumin on proliferation and apoptosis of human pterygium fibroblasts (HPF) in culture and search for a new method to prevent the recurrence after pterygium surgery, HPF was incubated with 0-160 μmol/L curcumin for 24-96 h. The MTT method was used to assay the biologic activities of curcumin at different time points and different doses. The expression of proliferating cell nuclear antigen (PCNA) in each group was detected by immunohistochemistry. The cell cycle distribution was detected by flow cytometry (FCM). Admini- stration of 20-80 μmol/L curcumin for 24-72 h could significantly inhibit HPF proliferation in a dose- and time-dependent manner (P<0.05). After treatment with curcumin at different concentrations of 20, 40, 80 and 160 μmol/L for 24 h, FCM revealed there was a significant sub-G1 peak at each concentration. The number of HPF in G0/G1 phase was increased, while in S phase, it was decreased (P<0.05). At the concentration of 20-80 μmol/L, curcumin, in a dose-dependent manner (P<0.05), could inhibit the expression of PCNA in HPF. It was suggesterd that curcumin could significantly in- hibit the proliferation of HPF, make HPF arrest in G0/G1 phase and induce the apoptosis of HPF in a dose- and time-dependent manner.