Silencing of ATPase Inhibitory Factor 1 Inhibits Cell Growth via Cell Cycle Arrest in Bladder Cancer.

OBJECTIVE: The role of the ATPase inhibitory factor 1 (IF1) is inhibit the hydrolase activity of F1Fo-ATPase when oxidative phosphorylation is impaired. It has been demonstrated that IF1 is overexpressed in various carcinomas and mediates tumor cell activities, but the detailed mechanisms of IF1-mediated tumor progression and the link between IF1 and cell cycle progression remain unclear. Herein, we aimed to investigate the potential role of IF1 in cell cycle progression of human bladder cancer (BCa). METHODS: The expression of IF1 was analyzed by immunohistochemistry in tumor tissues. Western blot was used to detect protein expression in the cells. Cell proliferation was determined by MTT and colony formation assays. The cell cycle was analyzed using flow cytometry. RESULTS: We firstly showed IF1 was overexpressed in BCa. Silencing of IF1 by small interfering RNA led to a significant decrease in cell proliferation and migration in T24 and UM-UC-3 cells. Importantly, IF1 knockdown caused cell cycle arrest at G0/G1 stage and decreased the protein level of cyclin E/cyclin-dependent kinases (cdk) 2 and/or cyclin D/cdk4/cdk6. CONCLUSION: These results suggest the inhibitory effect of IF1 knockdown on BCa cell proliferation is via the suppression of cyclins and cdks related to G1/S transition and then induction of G0/G1 arrest, and firstly indicate IF1 mediates the tumor cell cycle. We concluded that IF1 may be a novel therapeutic target for BCa.

Terrestrosin D, a steroidal saponin from Tribulus terrestris L., inhibits growth and angiogenesis of human prostate cancer in vitro and in vivo.

OBJECTIVE: The aim of this study was to investigate whether terrestrosin D (TED) inhibits the progression of castration-resistant prostate cancer and consider its mechanism. METHODS: Cell cycle, mitochondrial membrane potential (ΔΨm) and apoptosis were determined by flow cytometry. Caspase-3 activity and vascular endothelial growth factor secretion were detected by a caspase-3 assay and human vascular endothelial growth factor kit, respectively. A PC-3 xenograft mouse model was used to evaluate the anticancer effect of TED in vivo. RESULTS: In vitro, TED strongly suppressed the growth of prostate cancer cells and endothelial cells in a dose-dependent manner. TED induced cell cycle arrest and apoptosis in PC-3 cells and human umbilical vascular endothelial cells (HUVECs). TED-induced apoptosis did not involve the caspase pathway. TED also decreased ΔΨm in PC-3 cells and HUVECs. In vivo, TED significantly suppressed tumor growth in nude mice bearing PC-3 cells, without any overt toxicity. Immunohistochemical analysis showed TED induced apoptotic cell death and inhibited angiogenesis in xenograft tumor cells. CONCLUSION: Cell cycle arrest and induction of apoptosis in cancer cells and endothelial cells might be plausible mechanisms of actions for the observed antitumor and antiangiogenic activities of TED.

Inhibitory effects of secoiridoids from the roots of Gentiana straminea on stimulus-induced superoxide generation, phosphorylation and translocation of cytosolic compounds to plasma membrane in human neutrophils.

Gentiana straminea Maxim. has been used widely as a traditional Chinese medicine for the treatment of rheumarthritis, icterepatitis, constipation, pain and hypertension. Five secoiridoids, gentiopicroside (GTP), 6'-O-(2-hydroxy-3-O-ß-D-glucopyranosyl-benzoyl)-sweroside (HGBS), 6'-O-ß-D-glucosylgentiopicroside (GGTP), sweroside (SW) and swertiamarin (STM) were isolated from the roots of G. straminea. The effect of these secoiridoids on stimulus-induced superoxide generation in human neutrophils was assayed by measuring the reduction of ferricytochrome c. Tyrosyl or serine/threonine phosphorylation of neutrophil proteins, and translocation of the cytosolic compounds to the cell membrane were also investigated using specific monoclonal antibodies. The five secoiridoids used in the present experiment suppressed N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced superoxide generation in a concentration dependent manner. GTP and HGBS also suppressed phorbol 12-myristate 13-acetate (PMA) and arachidonic acid (AA)-induced superoxide generation. However, the other three secoiridoids showed no effect on PMA- and AA-induced superoxide generation. fMLP-, PMA- and AA-induced tyrosyl or serine/threonine phosphorylation and translocation of the cytosolic proteins to the cell membrane were suppressed in parallel with the suppression of the stimulus-induced superoxide generation.

A novel C-glycosylflavone from the leaves of Diospyros kaki.

A novel C-glycosylflavone with unusual alpha-orientation at the anomeric center of d-glucose was isolated from the leaves of Diospyros kaki. Its structure was determined as 8-C-[alpha-l-rhamnopyranosyl-(1 --> 4)]-alpha-d-glucopyranosylapigenin by chemical methods and spectral experiments.

Abnormal octadeca-carbon fatty acids distribution in erythrocyte membrane phospholipids of patients with gastrointestinal tumor.

Fatty acid (FA) composition is closely associated with tumorigenesis and neoplasm metastasis. This study was designed to investigate the differences of phospholipid FA (PLFA) composition in erythrocyte and platelet cell membranes in both gastrointestinal (GI) tumor patients and healthy controls.In this prospective study, 50 GI tumor patients and 33 healthy volunteers were recruited between the years 2013 and 2015. Blood samples were collected from healthy volunteers and patients, and FA composition was assessed using gas chromatography-mass spectrometer (GC-MS), and data were analyzed by multifactor regression analysis.Compared with healthy controls, the percentages of C18:0 (stearic acid, SA), C22:6 (docosahexaenoic acid, DHA), and n-3 polyunsaturated FAs (n-3 PUFA) were significantly increased, while C18:1 (oleic acid, OA), C18:2 (linoleic acid, LA), and monounsaturated FAs (MUFA) decreased in erythrocyte membranes of GI tumor patients. Also, patient's platelets revealed higher levels of C20:4 (arachidonic acid, AA) and DHA, and lower levels of OA and MUFA.Our study displayed a remarkable change in the FA composition of erythrocyte and platelet membranes in GI tumor patients as compared with healthy controls. The octadeca-carbon FAs (SA, OA, and LA) in erythrocyte membranes could serve as a potential indicator for GI tumor detection.

Anti-inflammatory effect of three iridoids in human neutrophils.

To verify the anti-inflammatory potency of iridoids, three iridoids (two natural, loganic acid: LA; geniposide: GE; and an artefact, 7(S)-n-butyl morroniside: BM) were investigated in vitro on the inhibition of superoxide generation in human neutrophils. All compounds showed inhibitory effect on fMLP-induced superoxide generation in a concentration-dependent manner with the following order: BM>LA>GE. BM exhibits potent inhibitory activity on superoxide anion induced by PMA, while LA and GE showed weak effect. When AA was used as stimulus, the generation of superoxide anion was suppressed by BM in a concentration-dependent manner. LA and GE exhibit both sides effect on superoxide generation.

Effects of five oleanolic acid triterpenoid saponins from the rhizome of Anemone raddeana on stimulus-induced superoxide generation, phosphorylation of proteins and translocation of cytosolic compounds to cell membrane in human neutrophils.

Five oleanolic acid triterpenoid saponins (OTS-1, 2, 3, 4 and 5) were isolated from the rhizome of Anemone raddeana. The effect of these triterpenoid saponins on stimulus-induced superoxide generation in human neutrophils was assayed by measuring the reduction of ferricytochrome c using a dual-beam spectrophotometer. The phosphorylation of neutrophil proteins, and translocation of p67(phox), p47(phox) and Rac to plasma membrane were investigated using specific monoclonal antibodies. The five oleanolic acid triterpenoid saponins used in this experiment suppressed N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced superoxide generation in a concentration-dependent manner. OTS-1, 2 and 4 suppressed phorbol 12-myristate 13-acetate (PMA)- and arachidonic acid (AA)-induced superoxide generation in a concentration-dependent manner, but OTS-3 and 5 showed no effect. fMLP- and PMA-induced tyrosyl or serine/threonine phosphorylation, and fMLP-, PMA- and AA-induced translocation of p67(phox), p47(phox) and Rac to plasma membrane were in parallel with the suppression of the stimulus-induced superoxide generation.

Qualitative and quantitative determination of ten iridoids and secoiridoids in Gentiana straminea Maxim. by LC-UV-ESI-MS.

A simple and accurate HPLC-UV/MS method was developed for the simultaneous determination of ten iridoids and secoiridoids in the roots of Gentiana straminea Maxim. Separations were performed on a Kromasil-C18 column by gradient elution using methanol and water containing phosphoric acid. Analytes were identified by HPLC coupled with ESI-MS experiments. The chromatographic method was validated for selectivity, linearity, precision, limit of detection, limit of quantification, accuracy, and stability. The developed assay could be considered as a suitable quality control method for G. straminea and other "Qinjiao" herbs.