Antibiotics, Antineoplastic ; pharmacology ; Apoptosis ; Cell Line, Tumor ; Doxorubicin ; pharmacology ; Gangliosides ; Humans ; NF-kappa B ; metabolism

BACKGROUNDBleomycin-induced fibrosis is extensively used to model aspects of the pathogenesis of interstitial pulmonary fibrosis. This study aimed to determine the benefic effects and mechanisms of simvastatin on bleomycin-induced pulmonary fibrosis in mice.

METHODSBleomycin-induced pulmonary fibrosis mice were administered with simvastatin in different doses for 28 days. We measured inflammatory response, fibrogenic cytokines and profibrogenic markers in both bleomycin-stimulated and control lungs, and correlated these parameters with pulmonary fibrosis.

RESULTSSimvastatin attenuated the histopathological change of bleomycin-induced pulmonary fibrosis and prevented the increase of lung hydroxyproline content and collagen (I and III) mRNA expression induced by bleomycin. Moreover, simvastatin down-regulated the increased expression of transforming growth factor-beta1 (TGF-beta1) and connective tissue growth factor (CTGF) induced by bleomycin at both gene and protein levels. Simultaneously, the accumulation of neutrophils and lymphocytes and the increased production of tumor necrosis factor-alpha (TNF-alpha) in bronchial alveolar lavage fluid were inhibited by simvastatin in early inflammatory phase after bleomycin infusion. The higher dose of simvastatin was associated with a more significant reduction in these inflammatory and fibrotic parameters. Furthermore, the inactivation of p38, RhoA and Smad2/3 signaling pathways was observed during simvastatin administration.

CONCLUSIONSSimvastatin attenuated bleomycin-induced pulmonary fibrosis, as indicated by decreases in Ashcroft score and lung collagen accumulation. The inhibitory effect of simvastatin on the progression of pulmonary fibrosis may be demonstrated by reducing inflammatory response and production of TGF-beta1 and CTGF. These findings indicate that simvastatin may be used in the treatment of pulmonary fibrosis.

Animals ; Antibiotics, Antineoplastic ; Bleomycin ; Mice ; Mice, Inbred C57BL ; Pulmonary Fibrosis ; chemically induced ; metabolism ; pathology ; Simvastatin ; pharmacology

This study was aimed to investigate the molecular mechanism of doxorubicin resistance in multiple myeloma cell line and certify the effect of Notch signal over-expression on drug resistance of myeloma cells. The doxorubicin RPMI 8226 cell line (RPMI8226/DOX) was established by culturing 8226 cells with continuous low concentration and intermittent gradually-increasing-concentration of doxorubicin in vitro, the mRNA expression of Notch2,Jagged1, Jagged2, HES1 were measured by RT-PCR and the P-170 protein expression was detected by Western blot in RPMI 8226 cell line; the changes of IL-6 and VEGF were tested by ELISA. The results showed that the Notch mRNA expression (Notch2, Jagged1, Jagged2 increased gradually along with the increase of chemotherapeutic drug resistance, but the expression of HESI mRNA gradually decreased along with the increase of drug resistance. The expression level of P-170 protein was upregulated gradually along with the increase of drug resistance. The level of VEGF and IL-6 in culture supernatants of RPMI8226/DOX was higher than that in RPMI 8226. It is concluded that the establishment of RPMI 8226/DOX cell line is a useful model to analyze the mechanism of chemotherapeutic drug resistance in multiple myeloma, Notch activation is closely correlated with the drug resistance of multiple myeloma and Notch signaling may to be used as a new target for multiple myeloma treatment.
Antibiotics, Antineoplastic ; pharmacology ; Cell Line, Tumor ; Doxorubicin ; pharmacology ; Drug Resistance, Neoplasm ; Humans ; Interleukin-6 ; Multiple Myeloma ; metabolism ; pathology ; Signal Transduction

OBJECTIVETo evaluate the effect of combination of glutamine (GLN) and mitomycin C (MMC) on the human gastric carcinoma cell line MGC-803 in vitro.

METHODSThe effects of GLN and MMC were measured by MTT assay, and the interaction between the two agents was evaluated by the median-effect principle. Flow cytometry was used for cell cycle analysis.

RESULTSGLN did not significantly stimulate the cell growth in vitro. High-concentration of GLN could inhibit the cell growth. MMC could effectively inhibit the cell growth in a time-dependent manner. The interaction of these two agents showed a weak antagonistic activity (1 < CI < 1.2703). MMC induced remarkable S-phase arrest. Low-dose GLN has limited effect on the S-phase arrest of MMC, while high-dose GLN significantly attenuated the S-phase arrest and lowered the proliferation index of MGC-803 cell.

CONCLUSIONSCombination of GLN and MMC has a a weak and dose-dependent antagonistic activity in the treatment of gastric carcinoma cell line MGC-803. The combination of high-dose MMC and low-dose GLN may achieve better efficacy.

Adenocarcinoma ; pathology ; Antibiotics, Antineoplastic ; pharmacology ; Cell Line, Tumor ; Dose-Response Relationship, Drug ; Drug Synergism ; Glutamine ; pharmacology ; Humans ; Mitomycin ; pharmacology ; Stomach Neoplasms ; pathology

OBJECTIVETo investigate the killing effect of ZD6474 combined with adriamycin (ADM) on MCF-7 human breast cancer cells.

METHODSThe inhibitory effects of ZD6474 and ADM alone and in combination on the proliferation of MCF-7 cells were assessed by MTT assay. The cell cycle and cell apoptosis were detected by flow cytometry.

RESULTSZD6474 and ADM both significantly inhibited the proliferation of MCF-7 cells, showing a synergistic effect of their reactions in combined use (P<0.05). ZD6474 or ADM alone caused cell cycle arrest at G0/G1 and S phases, respectively. Combined use of the two drugs resulted in significant reduction of the M-phase cell percentage and cell cycle arrest at G0/G1 and S phases. The coadministration of the drugs significantly increased the apoptosis rate of the cells as compared with ZD6474 or ADM treatment alone (P<0.05).

CONCLUSIONSZD6474 and ADM show a synergistic effect in inhibiting the proliferation and inducing apoptosis of MCF-7 cells.

Antibiotics, Antineoplastic ; pharmacology ; Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Breast Neoplasms ; pathology ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Doxorubicin ; pharmacology ; Drug Synergism ; Female ; Humans ; Piperidines ; pharmacology ; Quinazolines ; pharmacology

The objective of study was to investigate the effect of ribosomal protein L6 (RPL6) gene expression on the drug resistance of leukemia cells and its possible mechanism. RPL6 cDNA was obtained by RT-PCR, both sense and antisense cDNA recombinants of RPL6-encoding gene were constructed with pcDNA3. 1 (+) expression vector. Subsequently, the sense RPL6 cDNA recombinant was transfected into K562 cells while the antisense one into K562/A02 cells by liposomal reagent. The chemosensitivity, apoptosis and caspase-3 activity of K562 and K562/A02 cells were evaluated by MTT assay, flow cytometer and fluorometer respectively. The results indicated that expression of RPL6 in K562/A02 was higher than that in K562; resistance of sense-transfected K562 cells to doxorubicin was 325% of control cells, apoptosis and caspase-3 activity decreased (P<0.005); whereas resistance of antisense-transfected K562/A02 cells to adriamycin was 38% of control cells, apoptosis and caspase-3 activity significantly increased (P<0.005). It is concluded that RPL6 gene plays an important role in the development of drug resistance in K562/A02 cells by changing drug-induced apoptosis.
Antibiotics, Antineoplastic ; pharmacology ; Apoptosis ; genetics ; Doxorubicin ; pharmacology ; Drug Resistance, Neoplasm ; genetics ; Gene Expression Regulation, Leukemic ; Humans ; K562 Cells ; Ribosomal Proteins ; biosynthesis ; genetics

OBJECTIVETo study the role of mitogen-activated protein kinase (MAPK) pathway in the action mechanism of PYM-induced KB cell apoptosis.

METHODSWestern blot analysis was used to investigate the expression of the mitogen-activated protein kinase.

RESULTSWhen treated with PYM in cultured KB cells, the extracellular signal-regulated kinase (ERKl/2) showed a dose-and time-dependent decreasing in phosphorylation status of these proteins through a western blot analysis, whereas protein levels of p38 MAPK remained unchanged.

CONCLUSIONSThe mitogen-activated protein kinase (MAPK) pathway may play an important ro1e in PYM-induced apoptosis of KB cells.

Antibiotics, Antineoplastic ; pharmacology ; Apoptosis ; drug effects ; Bleomycin ; analogs & derivatives ; pharmacology ; Humans ; KB Cells ; Mitogen-Activated Protein Kinases ; physiology ; p38 Mitogen-Activated Protein Kinases

OBJECTIVETo investigate whether PTEN can increase sensitivity of Ishikawa cells, an endometrial carcinoma cell line, to doxorubicin.

METHODSIshikawa cells transfected by PTEN gene or not were separately treated with serial concentrations of doxorubicin. The sensitivity of cells to doxorubicin was determined by MTT assay. The cells were stained with Hoechst 33258 and examined under fluorescence microscope to determine cell apoptosis. Immunoprecipitation and Western blotting analysis were performed to evaluate the effects of doxorubicin on phosphorylation of Bad and Akt/PKB.

RESULTSDoxorubicin induced cell death of the PTEN-transfected and non-transfected Ishikawa cells in a dose-dependent manner, but the cell death was more significant in PTEN-expressing clones than in parental Ishikawa cells. A low concentration of doxorubicin (0.1 micromol/L) did not affect cell apoptosis in PTEN-null Ishikawa cells, but it induced cell apoptosis in PTEN-expressing clones. A high concentration of doxorubicin (1 micromol/L) induced cell apoptosis in both cell lines. However, the percentage of apoptotic cells was higher in PTEN-expressing clones than that in parental Ishikawa cells. In the PTEN-expressing clones, expression of phospho-Akt/PKB and phospho-Bad (Ser-136) was down regulated. Doxorubicin reduced the levels of phospho-Akt/PKB and phospho-Bad (Ser-136) in both cell lines, but the most significant reduction occurred in the PTEN-expressing clones.

CONCLUSIONPTEN significantly enhances chemosensitivity of Ishikawa cells to doxorubicin. With PTEN expression, doxorubicin may exert apoptosis-induction activity by downregulation of the PI3k/Akt/PKB signaling pathway in Ishikawa cells.

Adenocarcinoma ; genetics ; pathology ; Antibiotics, Antineoplastic ; pharmacology ; Apoptosis ; drug effects ; Cell Line, Tumor ; Doxorubicin ; pharmacology ; Endometrial Neoplasms ; genetics ; pathology ; Female ; Humans ; PTEN Phosphohydrolase ; biosynthesis ; genetics ; Transfection

OBJECTIVETo determine whether mycophenolic acid (MPA) exerts an apoptotic effect on human leukemic T cells Molt-4 and to elucidate its possible mechanism.

METHODSCell morphology, DNA fragmentation, cell cycle,percentage of annexin V positive cells and enzymatic activity of caspase-3 were measured by microscopic, electrophoretic and flow cytometric techniques respectively. Human leukemic B cell line Raji was used as control.

RESULTMPA could induce apoptosis of Molt-4 cells with dose-and time-dependent manners; cells were blocked in the S phase. The activity of caspase-3 was enhanced in a dose-dependent manner in Molt-4 cells treated with MPA for 24 h. MPA could not induce apoptosis in Raji cells.

CONCLUSIONMPA can induce apoptosis in Molt-4 cells which may be involved in the activation of caspase-3.

Antibiotics, Antineoplastic ; pharmacology ; Apoptosis ; drug effects ; Caspase 3 ; Caspases ; metabolism ; Dose-Response Relationship, Drug ; Humans ; Leukemia, T-Cell ; pathology ; Mycophenolic Acid ; pharmacology ; Time Factors ; Tumor Cells, Cultured

To provide the profiles of metabolism of mitomycin C (MMC) by human liver microsomes in vitro, MMC was incubated with human liver microsomes, then the supernatant component was isolated and detected by HPLC. Types of metabolic enzymes were estimated by the effect of NADPH or dicumarol (DIC) on metabolism of MMC. Standard, reaction, background control (microsomes was inactivated), negative control (no NADPH), and inhibitor group (adding DIC) were assigned, the results were analyzed by Graphpad Prism 4. 0 software. Reaction group compared with background control and negative control groups, 3 NADPH-dependent absorption peaks were additionally isolated by HPLC after MMC were incubated with human liver microsomes. Their retention times were 10. 0, 14. 0, 14. 8 min ( named as Ml, M2, M3) , respectively. Their formation was kept as Sigmoidal dose-response and their Km were 0. 52 (95% CI, 0. 40 - 0.67) mmol x L(-1), 0. 81 (95% CI, 0. 59 - 1. 10) mmol x L(-1), 0. 54 (95% CI, 0. 41 -0. 71) mmol x L(-1) , respectively. The data indicated that the three absorption peaks isolated by HPLC were metabolites of MMC. DIC can inhibit formation of M2, it' s dose-effect fitted to Sigmoidal curve and it' s IC50 was 59. 68 (95% CI, 40. 66 - 87. 61) micromol x L(-1) , which indicated DT-diaphorase could take part in the formation of M2. MMC can be metabolized by human liver microsomes in vitro, and at least three metabolites of MMC could be isolated by HPLC in the experiment, further study showed DT-diaphorase participated in the formation of M2.
Antibiotics, Antineoplastic ; metabolism ; Chromatography, High Pressure Liquid ; methods ; Dicumarol ; pharmacology ; Dose-Response Relationship, Drug ; Enzyme Inhibitors ; pharmacology ; Humans ; Microsomes, Liver ; drug effects ; enzymology ; metabolism ; Mitomycin ; metabolism