OBJECTIVETo investigate the anti-tumor effects of melittin against malignant human glioma cells in vitro.

METHODSTwo malignant human glioma cell lines (U87 and U251) were treated with melittin at various concentrations, and the cell growth inhibition and apoptosis were evaluated using MTT assay, flow cytometry and agarose gel electrophoresis.

RESULTSMelittin could obviously inhibit the proliferation of the two glioma cell lines (P<0.05). At the concentrations of 1, 10, 20, 40, 80, 160, 200 mg/L, melittin resulted in U87 cell apoptosis rates of 12.80%, 16.92%, 22.69%, 34.05%, 41.82%, 59.87%, and 80.25%, and in U251 cell apoptosis rate of 11.61%, 16.21%, 22.03%, 30.57%, 41.10%, 58.33%, and 79.12%, respectively, showing a dose-dependent effect in its action of inducing cell apoptosis.

CONCLUSIONMelittin inhibits the proliferation and induces apoptosis of malignant human glioma cell lines in vitro.

Apoptosis ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Glioma ; metabolism ; pathology ; Humans ; Melitten ; pharmacology

OBJECTIVE: To investigate the effect of quercetin (Que) on HEN1 cells, a kind of human nasopharyngeal carcinoma cells. METHOD: Inhibition rate of quercetin on HEN1 was assayed by MTT method, cell apoptosis by flow cytometry (FCM), Caspase-3 expression of each group were determined by colorimetry set. RESULT: The inhibition of quercetin on HEN1 cells was shown in the dose-dependent (r = 0.709, P < 0.05) and time-dependent manner (r = 0.703, P < 0.01). The ratio of apoptotic and necrosis cells increased accompanied with added quercetin concentration. Cell cycle was specificly arrested inG2/M phase. Apoptosis cusp was revealed by FCM. While the activity of caspase-3 were also significantly upregulated in five groups after quercetin compared to control (P < 0.05). CONCLUSION Quercetin can activate the expression of Caspase-3 and induce the apoptosis of HEN1 cells through mitochondrion-depended pathway.
Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Humans ; Nasopharyngeal Neoplasms ; metabolism ; pathology ; Quercetin ; pharmacology

OBJECTIVETo investigate the effect of 1,25 (OH)(2)D(3) on cell proliferation and the expression of tumor necrosis factor-α (TNF-α ) in human gastric carcinoma SGC-7901 cells.

METHODSSGC-7901 cells were treated with 1×10(-6), 1×10(-7), 1×10(-8), and 1×10(-9) mol/L 1,25 (OH)(2)D(3) for 24, 48, 72 and 96 h. The cell proliferation was measured by MTT assay, and the cell cycle changes were analyzed using flow cytometry. RT-PCR and Western blotting were used to determine the expression of TNF-α mRNA and protein, respectively.

RESULTS1,25 (OH)(2)D(3) significantly inhibited SGC-7901 cell proliferation (P<0.05) in a time- and dose-dependent fashion. Treatment with 1,25 (OH)(2)D(3) for 72 h caused significant cell cycle arrest at G(0)/G(1) phase (F=9.81, P<0.05) and dose-dependently inhibited the expression of TNF-α at both mRNA and protein levels in SGC-7901 cells (P<0.05).

CONCLUSIONThe inhibitory effect of 1,25 (OH)(2)D(3) on SGC-7901 cell proliferation is probably associated with the down- regulation of TNF-α expression.

Calcitriol ; pharmacology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Humans ; Stomach Neoplasms ; metabolism ; pathology ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo explore the effects of toosendanin in inducing apoptosis of human hepatocarcinoma cell line SMMC-7721 and Hep3B, and its influence on the related genes, Bcl-2, Bax and Fas.

METHODSThe inhibitory rate of cell proliferation and cell growth curve were detected by MTT assay; morphological changes of cells were observed by inverted microscope; early stage apoptosis rate were detected by Annexin V-FITC/PI assay; relative activities of Caspase-3,-8 and-9 were analyzed by spectrophotometry; and the expressions of Bcl-2, Bax and Fas were detected using immunohistochemistry assay.

RESULTSToosendanin presented significant inhibitory effect on proliferation of hepatocarcinoma cells in a time- and dose-dependent manner. After toosendanin treatment, the amount of cells was significantly reduced, shrunk in size and rounded in shape, with decreased adhesion ability. The apoptosis rates of SMMC-7721 cells and Hep3B cells treated with 0.5 micromol/L toosendanin for 72 h were 21.55% and 18.35% respectively, which were reduced after z-VAD-fmk (inhibitor of Caspase) treatment. The activities of Caspase-3,-8 and -9 all markedly enhanced after treatment in SMMC-7721 cells, while in Hep3B cells, activities of Caspase-3 and -9 enhanced, but that of Caspase-8 unchanged. As compared with the control group, after toosendanin treatment, expression of Bcl-2 decreased, and that of Bax and Fas increased in SMMC-7721 cells; but in Hep3B cells the expression of Bcl-2 decreased, that of Bax increased, and expression of Fas unchanged.

CONCLUSIONSToosendanin could inhibit the proliferation and induce the apoptosis of both P53 and P53 human hepatocarcinoma cells, which involved the participation of mitochondria-dependent pathway. So it may be a kind of natural anti-cancer drug, playing its effect through P53 independent pathway.

Apoptosis ; drug effects ; Carcinoma, Hepatocellular ; metabolism ; pathology ; Cell Line, Tumor ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Liver Neoplasms ; metabolism ; pathology ; Mitochondria ; drug effects ; metabolism ; Tumor Suppressor Protein p53 ; metabolism

OBJECTIVETo investigate miRNA-221 expression in human colorectal carcinoma (CRC) cells and the effects of miR-221-specific inhibitor on the proliferation and apoptosis of CRC cells.

METHODSFour human CRC cell lines (HT-29, Lovo, SW-480, and CaCO2) were examined for miRNA-221 expression using real-time Q-PCR. The specific 2,-methoxy-modified RNA oligonucleotides of miR-221 (anti-miR-221) were synthesized and transfected into Caco2 cells via liposome, and the changes in the expression of miR-221 in the cells were detected by real-time Q-PCR. The proliferation and apoptosis of the transfected CRC cells were detected using MTT assay and flow cytometry.

RESULTSThe 4 human CRC cells showed significantly upregulated expression of miR-221 compare with HUVECs (P<0.01). The miR-221-specific inhibitor, anti-miR-221, significantly inhibited the expression of miR-221 in Caco2 cells and suppressed the cell proliferation, causing also obvious cell apoptosis (P<0.01).

CONCLUSIONThe miR-221-specific inhibitor shows potent inhibitory effect on the growth of CRC cells, suggesting its value as a potential anti-tumor candidate for treatment of CRC.

Apoptosis ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Colorectal Neoplasms ; pathology ; Humans ; MicroRNAs ; antagonists & inhibitors ; metabolism

OBJECTIVETo study the effect of valproate acid sodium(VPA) on apoptosis of human gastric cancer cell BGC-823 and to explore its possible mechanism.

METHODSCell growth inhibition was examined by MTT assay. Apoptosis rate was detected by FCM with Annexin V/PI staining. The activities and protein expression levels of caspase 3, caspase 8 and caspase 9 were examined by spectrophotometry and indirect immunofluorescence technique respectively.

RESULTSThe growth inhibition rate and apoptosis rate of human gastric cancer cells, treated with 0.75-4.00 mmol/L VPA for 24 h and 48 h, elevated in time- and dose-dependent manner. Apoptosis rates of VPA 0.75 mmol/L 24 h and 48 h were (7.2 +/- 0.5)% and (9.2 +/- 1.0)%, of VPA 4.00 mmol/L 24 h and 48 h were (16.7 +/- 2.2)% and (20.4 +/- 1.6)% respectively, which were significantly different as compared to the control [24 h, (4.9 +/- 0.2)%, 48 h, (5.1 +/- 0.8)%] (P< 0.001). The activities and protein expression levels of caspase 3 and caspase 9 were up-regulated compared with the control group (P< 0.001), meanwhile the activity and protein expression of caspase 8 enhanced slightly after VPA treatment for 48 h.

CONCLUSIONVPA can inhibit the growth and induce the apoptosis of BGC-823 cells mainly through the activation of caspase 9 pathway.

Apoptosis ; drug effects ; Caspases ; metabolism ; Cell Line, Tumor ; Humans ; Stomach Neoplasms ; pathology ; Valproic Acid ; pharmacology

OBJECTIVETo investigate the effect of bufalin on nucleus-mitochondria localization of human telomerase reverse transcriptase(hTERT) by exploring its effect on proliferation and apoptosis in human esophageal squamous carcinoma EC9706 cells.

METHODSEC9706 cells were treated with bufalin at various concentrations, and then the cell growth inhibition of EC9706 cells was examined by CCK-8 assay and the 50% inhibitory concentration (IC(50)) was calculated.Cell cycle analysis was performed by flow cytometry with PI staining, and nucleus morphology of apoptosis were observed by fluorescence microscopy with Hoechst 33342 staining. The apoptotic index was measured by flow cytometry with Annexin V-FITC/PI double staining. hTERT subcellular localization and protein expression were determined by Western blotting and multiple immunofluorescence labling combined with laser confocal scanning microscopy.

RESULTSThe proliferation of EC 9706 cells was significantly inhibited by bufalin along with the increase of processing time and concentrations (p<0.01). After the EC9706 cells were exposed to 100 nmol/L bufalin,the number of cells gradually decreased in G(1) phase and increased in S and G(2)/M phases(p<0.05). The typical nucleus morphological changes of apoptosis were observed and the apoptotic index was increased(p<0.01). The expression of hTERT decreased in nucleus but increased in mitochondria(p<0.05).

CONCLUSIONSBufalin can inhibit the proliferation of human esophageal squamous carcinoma EC9706 cells in a time- and dose-dependent manner. It can arrest cell cycle in S and G(2)/M phases and induce the apoptosis of EC 9706 cells. hTERT is localized in both nucleus and mitochondria,and can be partially translocated from nucleus to mitochondria during the bufalin-induced apoptosis.

Apoptosis ; drug effects ; Bufanolides ; pharmacology ; Carcinoma, Squamous Cell ; metabolism ; pathology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Esophageal Neoplasms ; metabolism ; pathology ; Humans ; Telomerase ; metabolism

The aim of this study was to evaluate the effects of low concentrations of DEHP and MEHP on steroidogenesis in a murine Leydig tumor cell line (MLTC-1) in vitro. The result of flow cytometry analysis revealed that the proportion of apoptotic cells was significantly increased after the exposure to DEHP. All three genes (P450scc, P450c17, and 3βHSD) under study showed an increased expression following exposure to DEHP or MEHP, although some insignificant inhibitory effects appeared in the 10 μmol/L treatment group as compared with the controls. It was also found that compared with the controls. It was also found that DEHP or MEHP stimulated INSL3 mRNA and protein especially in the 0.001 μmol/L treatment group. Testosterone secretions were stimulated after the exposure to DEHP or MEHP. Alternations of steroidogenic enzymes and INSL3 in MLTC-1 cells might be involved in the biphasic effects of DEHP/MEHP on androgen production.
Animals ; Apoptosis ; drug effects ; Cell Line, Tumor ; Diethylhexyl Phthalate ; analogs & derivatives ; toxicity ; Leydig Cell Tumor ; metabolism ; pathology ; Mice ; Steroids ; biosynthesis

OBJECTIVETo study the effect of safflower injection on the proliferation and apoptosis of human leukemia cell line HEL and the relevant molecular mechanisms.

METHODSHEL cells were treated with different concentrations of safflower injection. HEL cells without safflower injection treatment were used as the control group. MTT method was used to detect the inhibitory rate of the HEL cells at 24, 48 and 72 hours after various concentrations of safflower injection treatment (10, 20, 30, 40 and 50 mg/mL). The cell cycle and apoptosis were detected using flow cytometry and the HOXB3-mRNA expression was measured by RT-PCR at 48 hours after safflower injection treatment (10, 20 and 30 mg/mL).

RESULTSCompared with the control group, various concentrations of safflower injection inhibited HEL cell proliferation in a dose-dependent manner (P<0.05). At 48 hours after various concentrations of safflower injection treatment, the number of treated cells in the G2/M phase increased, but that in the S phase decreased, and the apoptosis rate was significantly higher than that in the control group, with a dose-dependent manner (P<0.05). The expression of HOXB3-mRNA in safflower injection-treated cells decreased in a dose-dependent manner compared with the control group (P<0.05).

CONCLUSIONSSafflower injection can inhibit proliferation and induce apoptosis of HEL cells in vitro, and its underlying mechanisms may involve down-regulation of the HOXB3-mRNA expression.

Apoptosis ; drug effects ; Carthamus tinctorius ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Homeodomain Proteins ; genetics ; Humans ; Injections ; Leukemia ; drug therapy ; metabolism ; pathology

OBJECTIVETo investigate the therapeutic value of inhibiting the expression of insulin-like growth factor-I receptor (IGF-IR) using picropodophyllin (PPP) by studying the effects on proliferative and metastatic potentials of human hepatocellular carcinoma (HCC) using an in vitro cultured cell system.

METHODSIGF-IR expression in human HCC cell lines (Bel-7404, Bel-7402, HepG2, and Huh-7) and human hepatocytes (L02) was assessed at baseline (pre-treatment) and after PPP treatment by western blotting. Changes in cell cycle were analyzed by flow cytometry and in cell viability by sulforhodamine B staining. Early apoptosis was detected by annexin-V/FITC and propidium iodide double-staining assay. Caspase-3/7 activity was suppressed by z-VAD-FMK and analyzed by homogeneous luminescence assay. Effects on cell motility were tested by wound-scratch test. Between-group differences were assessed by t-test or one-way analysis of variance.

RESULTSIGF-IR was markedly up-regulated in all HCC cell lines (vs. non-hepatoma hepatocytes). HCC cells with PPP-inhibited IGF-IR showed time-dependent decreases in cell motility and viability. After treatment with PPP for 24 hours, the proportion of HCC cells in G1 phase was 2.1% +/- 0.4%, in S phase was 11.0% +/- 0.7%, and in G2/M phase was 87.1% +/- 0.6%, and no healing was observed in the wound-scratch assay. The PPP treatment induced cell apoptosis, as evidenced by enhanced caspase-3/7 activity; the proportion of annexin-V+/PI- cells was significantly higher in the HepG2 cells than in the non-hepatoma hepatocytes (16.4% +/- 0.4% vs. 5.8% +/- 0.2%, t = 14.05, P less than 0.01). After z-VAD-FMK treatment, the apoptosis rate was significantly higher in the HepG2 cells than in the non-hepatoma hepatocytes (11.3% +/- 0.7% vs. 5.8% +/- 0.2%, t = 11.83, P less than 0.01).

CONCLUSIONIGF-IR is associated with proliferation, cell motility, and apoptosis of HCC cells, and may be a promising molecular target for HCC.

Apoptosis ; drug effects ; Carcinoma, Hepatocellular ; metabolism ; pathology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Humans ; Liver Neoplasms ; metabolism ; pathology ; Podophyllotoxin ; analogs & derivatives ; pharmacology ; Receptor, IGF Type 1 ; metabolism