BACKGROUND: Although pulmonary resection is the standard approach for the management of pulmonary metastases from soft tissue sarcoma, most of them are unresectable and chemotherapy remains the only option. The effectiveness of the cytotoxic drugs may be limited by the toxicities that occur before the therapeutic dose is reached. The regional administration of doxorubicin using pulmonary arterial perfusion in a rodent model can produce 10 to 25 times higher concentrations in the lung than systemic administration with minimal systemic toxicities. However, it is unclear whether a high concentration of doxorubicin has beneficial effects for killing cancer cells. MATERIAL AND METHOD: We studied this to evaluate the dose-dependent cytotoxic and apoptotic effects of doxorubicin on methylcholanthrene-induced rat fibrosarcoma(MCA) cells. This study examined the cytotoxicity and apoptosis-related gene expressions(Fas, FasL, Bax, caspase 1, caspase 2, caspase 8, Bcl-2, Bcl-xL, Bcl-xS) in MCA cells after 24 hours exposure to various concentrations of doxorubicin such as 1, 5, 10, 50, and 100 micrometer. RESULT: Dose-dependent cytotoxicity was observed after 24 hours exposure to doxorubicin. However, peak apoptosis after 24 hours exposure was observed at 5 micrometer of doxorubicin. Above 5 micrometer, apoptotic activity was decreased with dose-increment. All mRNA levels of apoptosis-related genes after 24 hours exposure were up-regulated above the control level at 1 micrometer of doxorubicin and then decreased by doxorubicin dose-increment except caspase 8, which showed higher levels than the control level at 5 micrometer. Apoptosis-related protein levels were highest at 1 micrometer of doxorubicin and then decreased by doxorubicin dose-increment. However, Bax and Bcl-xL proteins steadily showed higher levels than the control throughout the different concentrations of doxorubicin. CONCLUSION: These results suggest that apoptosis is the main cytotoxic mechanism in low concentrations of doxorubicin in MCA cells and apoptosis-related genes, such as Bax, caspase 8, a can kill MCA cells, even when apoptosis is inhibited, and have its propriety for achieving much cytotoxicity against MCA cells.
Animals ; Apoptosis* ; bcl-X Protein ; Caspase 1 ; Caspase 2 ; Caspase 8 ; Doxorubicin* ; Drug Therapy ; Fibrosarcoma ; Homicide ; Lung ; Neoplasm Metastasis ; Perfusion ; Rats* ; RNA, Messenger ; Rodentia ; Sarcoma

PURPOSE: NS398, a selective COX-2 inhibitor, is known to inhibit the growth of COX-2 expressing hepatocellular carcinoma cells. The present study investigated whether the cytotoxic effect of NS398 was COX-2 dependent and whether caspases were involved in NS398-induced apoptosis in hepatocellular carcinoma cells. MATERIALS AND METHODS: The expressions of COX-2 in SNU 423 and SNU 449 hepatocellular carcinoma cell lines were examined using RT-PCR and Western blot. The cytotoxic effect of NS398 was measured using MTT in the presence or absence of caspase inhibitors. The distribution of the cell cycle and extent of apoptosis were analyzed using flow cytometry and a Cell Death Elisa kit, respectively. RESULTS: The expression of COX-2 was observed in SNU423 cells, but not in SNU 449 cells. NS398 treatment resulted in both dose-and time-dependent growth inhibitions, with increases in apoptotic cells in both cell lines. Treatment with the pan-caspase inhibitor, z-VAD- fmk, or the caspase-3 inhibitor, Ac-DMQD-CHO, showed no attenuation of the cytotoxic effect of NS398 in either cell line. CONCLUSIONS: This study demonstrated that the cytotoxic effect of NS398 was independent of COX-2 expression. Caspases were also shown not to be involved in NS398-induced apoptosis in either SNU 423 or SNU 449 Korean HCC cell lines. Our data suggests the feasibility of preventing hepatocellular carcinoma with the use of COX-2 inhibitors needs to be carefully evaluated.
Apoptosis* ; Blotting, Western ; Carcinoma, Hepatocellular* ; Caspase 3 ; Caspase Inhibitors ; Caspases ; Cell Cycle ; Cell Death ; Cell Line* ; Cyclooxygenase 2 ; Cyclooxygenase 2 Inhibitors ; Enzyme-Linked Immunosorbent Assay ; Flow Cytometry

This study was aimed to investigate the effect of baicalin on proliferation and apoptosis of HL-60 cells and its mechanism. Cell proliferation was assayed by using Cell Counting Kit-8. The morphological changes of HL-60 cells were examined by light microscopy and nucleolus morphological changes were observed by fluorescent microscopy after Hoechst 33342 staining. The early cell apoptosis was detected by using flow cytometry with Annexin V-FITC/PI double staining. The expression of caspase-3, caspase-9, Bcl-2 and Bax mRNA was detected by RT-PCR and Western blot assay was carried out to examine Bax, Bcl-2, caspase-8 and cleaved caspase-3 expression. The results showed that Baicalin inhibited the proliferation of HL-60 cells in a time- and concentration-dependent manner. HL-60 cells exhibited typical morphological features (for example, cell shrinkage, membrane blebbing and formation of apoptotic bodies). Cell apoptosis in early stage could be detected, the expression of caspase-3, caspase-9 and Bax mRNA was obviously up-regulated, while the Bcl-2 expression down-regulated, and accordingly Bcl-2/Bax ratio decreased. Such results were consistent with the expression of these proteins. In addition, the expression of cleaved caspase-8 protein was induced significantly after treated with baicalin. It is concluded that baicalin can significantly inhibit the proliferation of HL-60 cells and induce the apoptosis of HL-60 cells, which may occur through decreasing Bcl-2/Bax ratio by intrinsic pathway and through extrinsic pathway. It suggests that baicalin may be a promising drug for the therapy of acute myeloid leukemia.
Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Caspase 8 ; metabolism ; Caspase 9 ; metabolism ; Cell Proliferation ; drug effects ; Flavonoids ; pharmacology ; HL-60 Cells ; Humans ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; bcl-2-Associated X Protein ; metabolism

OBJECTIVE: In vitro studies have revealed that treatment of various human cancer cell lines with specific cyclooxygenase 2 (COX-2) inhibitors induces apoptotic cell death. The goal of this article is to investigate the benefits of combining COX-2 inhibitors with existing treatment modalities in the management of ovarian cancer. METHODS: In this study we sought to determine the effects of combining paclitaxel and the COX-2 inhibitor celecoxib on apoptosis of epithelial ovarian cancer (EOC) cells. SK-OV-3 cells were exposed to increasing concentrations of paclitaxel (10(-7) M, 10(-6) M and 10(-5) M) and celecoxib (10(-8) M, 10(-7) M, 10(-6) M, 10(-5) M and 10(-4) M) as well as a combination of both drugs. The activity of apoptosis was evaluated by the morphologic examination and the MTT assay. The pattern of apoptosis was also assessed by the caspase-3 activity and the fraction of cleaved PARP (poly ADP-ribose polymerase) protein. RESULTS: Single application of both drugs could significantly increase the rate of apoptosis after 24 hours of continuous exposure. But concomitant treatment of SK-OV-3 EOC cell line with paclitaxel and celecoxib resulted in marked impairment of paclitaxel-induced apoptosis. The pattern of apoptosis induced by paclitaxel on SK-OV-3 EOC cell line was caspase-3 independent. CONCLUSION: Combining COX-2 inhibitors and paclitaxel does not have an additive or synergistic tumoricidal effect. On the contrary, celecoxib treatment markedly inhibited the apoptotic effects of paclitaxel in SK-OV-3 EOC cell line.
Adenosine Diphosphate Ribose ; Apoptosis* ; Caspase 3 ; Cell Death ; Cell Line* ; Cyclooxygenase 2 ; Cyclooxygenase 2 Inhibitors ; Humans ; Ovarian Neoplasms* ; Paclitaxel ; Celecoxib

Human skin cells undergo pathophysiological processes via generation of reactive oxygen species (ROS) upon excessive exposure to ultraviolet B (UVB) radiation. This study investigated the ability of hesperidin (C28H34O15) to prevent apoptosis due to oxidative stress generated through UVB-induced ROS. Hesperidin significantly scavenged ROS generated by UVB radiation, attenuated the oxidation of cellular macromolecules, established mitochondrial membrane polarization, and prevented the release of cytochrome c into the cytosol. Hesperidin downregulated expression of caspase-9, caspase-3, and Bcl-2-associated X protein, and upregulated expression of B-cell lymphoma 2. Hesperidin absorbed wavelengths of light within the UVB range. In summary, hesperidin shielded human keratinocytes from UVB radiation-induced damage and apoptosis via its antioxidant and UVB absorption properties.
Absorption ; Apoptosis* ; bcl-2-Associated X Protein ; Caspase 3 ; Caspase 9 ; Cytochromes c ; Cytosol ; Hesperidin* ; Humans* ; Keratinocytes* ; Lymphoma, B-Cell ; Mitochondrial Membranes ; Oxidative Stress* ; Reactive Oxygen Species ; Skin

PURPOSE: This study examined the effects of Tacrolimus (FK506) on the expression of the apoptotic signal transduction proteins of Jurkat human T-lymphocytes. METHODS: The cell viability was examined by a MTT assay, DAPI stain, enzyme activity of caspase family proteins, and western blotting for Bcl-2, Bak, Fas, and Fas-L. The cells were cultured in the presence or absence of FK506. FK506 induced cell death was confirmed to be apoptosis by the observation of nuclear fragmentation. RESULTS: The viability of Jurkat cells was decreased by the addition of FK506 in a dose- and time- dependent manner. The FK506 induced activation of caspase-3 protease was observed. FK506 didn't increase the catalytic activity of caspase -6, -8, and -9 proteases of Jurkat cells in a time-dependent manner. The viability was improved when a caspase-3 inhibitor was added. However, the caspase-9 inhibitor did not affect the viability. Bak protein expression was increased, and the Bcl-2 protein was decreased for some time. The expression of Fas and Fas-L were unaffected by FK506. CONCLUSION: FK506 induces dose- and time-dependent apoptotic cell death, and enhances the apoptosis of Jurkat cell by increasing the expression of Bak and caspase-3.
Apoptosis ; bcl-2 Homologous Antagonist-Killer Protein ; Blotting, Western ; Caspase 3 ; Caspase 9 ; Cell Death ; Cell Survival ; Humans ; Jurkat Cells ; Peptide Hydrolases ; Signal Transduction* ; T-Lymphocytes ; Tacrolimus*

OBJECTIVETo investigate the inhibitory effect of tetramethylpyrazine (Tet) preconditioning on overload training-induced myocardial apoptosis in rats, and to explore cardioprotective mechanisms of Tet preconditioning.

METHODSA total of 25 male Sprague-Dawley rats were randomly divided into three groups, including the control group (n=5), the overload training group (overload training for 8 weeks, n=10), and the Tet preconditioning group (Tet preconditioning for 8 weeks before overload training, n=10). After 8 weeks, cardiac structure and myocardial apoptosis were analyzed by histology, transmission electron microscopy, and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay staining. The expressions of Bcl-2, Bax, Caspase-3, and Caspase-9 in myocardium were evaluated by immunohistochemical staining.

RESULTSOverload training caused swelling, disorder, partial rupture, and necrosis of myocardial focal necrotic fibers, as well as mitochondrial vacuolization, cristae rupturing, and blurring. In contrast, Tet preconditioning attenuated the swelling of myocardial fibers, decreased the amount of ruptured fibers, and inhibited mitochondrial vacuolization, resulting in clear cristae. Overload training significantly increased Bax expression and decreased Bcl-2/Bax ratio when compared with the control group (P<0.01). Conversely, Tet preconditioning significantly increased Bcl-2 expression and the Bcl-2/Bax ratio as compared with the overload training group (P<0.05). Overload training dramatically increased the expressions of Caspase-3 and Caspase-9 when compared with the control groupP<0.05). Following Tet preconditioning, the expression of Caspase-3 was significantly reduced compared with the overload training group (P<0.05), while Caspase-9 expression showed a slight decline (P>0.05).

CONCLUSIONTet preconditioning increased the expression of Bcl-2 and reduced the expression of Caspase-3, thereby attenuating overload training-induced myocardial apoptosis, protecting against overload training-induced myocardial injury, and reducing damage to the myocardium due to overload training.

Animals ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Caspase 9 ; metabolism ; Immunohistochemistry ; Male ; Myocardium ; enzymology ; pathology ; ultrastructure ; Pyrazines ; pharmacology ; Rats, Sprague-Dawley ; bcl-2-Associated X Protein ; metabolism

PURPOSE: The mechanical insights of death of cancer cells by ionizing radiation are not yet clearly defined. Recent evidences have demonstrated that radiation therapy may induce cell death via activation of signaling pathway for apoptosis in target cells. This study is designed whether ionizing radiation may activate the signaling cascades of apoptosis including caspase family cysteine proteases, Bcl2/Bax, cytochrome c and Fas/Fas-L in target cells. MATERIALS AND METHODS: HL-60 cells were irradiated in vitro with 6 MV X-ray at dose ranges from 2 Gy to 32 Gy. The cell viability was tested by MTT assay and the extent of apoptosis was determined using agarose gel electrophoresis. The activities of caspase proteases were measured by proteolytic cleavages of substrates. Western blot analysis was used to monitor PARP, Caspase-3, Cytochrome-c, Bcl-2, Bax, Fas and Fas-L. RESULTS: Ionizing radiation decreases the viability of HL-60 cells in a time and dose dependent manner. Ionizing radiation-induced death in HL-60 cells is an apoptotic death which is revealed as characteristic ladder-pattern fragmentation of genomic DNA over 16 Gy at 4 hours. Ionizing radiation induces the activation of caspase-2, 3, 6, 8 and 9 of HL-60 cells in a time-dependent manner. The activation of caspase-3 protease is also evidenced by the digestion of poly (ADP-ribose) polymerase and procaspase- 3 with 16Gy ionizing irradiation. Anti-apoptotic Bcl2 expression is decreased but apoptotic Bax expression is increased with mitochondrial cytochrome c release in a time- dependent manner. In additon, expression of Fas and Fas-L is also increased in a time dependent manner. CONCLUSION: These data suggest that ionizing radiation-induced apoptosis is mediated by the activation of various signaling pathways including caspase family cysteine proteases, Bcl2/Bax, Fas and Fas-L in a time and dose dependent manner.
Apoptosis ; Blotting, Western ; Caspase 2 ; Caspase 3 ; Cell Death ; Cell Survival ; Cysteine Proteases ; Cytochromes c ; Digestion ; DNA ; Electrophoresis, Agar Gel ; HL-60 Cells* ; Humans ; Peptide Hydrolases ; Radiation, Ionizing

OBJECTIVE: To investigate the effect of 2-methoxyestradiol (2-ME2) to lymphoma Raji cells and its mechanism. METHODS: Different concentrations of 2-ME2 were used to treat lymphoma Raji cells. CCK8 method was used to detect the effect of 2-ME2 to proliferation of Raji cells. Flow cytometry FITC/PI double labeling method was used to detect early apoptosis of the cells. Western blotting was used to detect the effect of 2-ME2 to the expression of BCL-2, Bax, Caspase-3 and C-myc proteins in Raji cells. RESULTS: 2-ME2 significantly inhibited the proliferation of Raji cells. The inhibition rate increased with the increasing of drug concentration, and increased significantly with the prolongation of drug treatment time (r=0.9215). Flow cytometry FITC/PI double staining showed that the apoptotic rate of 2.5 μmol/L 2-ME2 treatment group was (33.79±1.63) %, while the apoptosis rate of the 48 h group was (51.90±2.72) %, and that of the control group was (7.08±0.36) %. After treated with 2.5 μmol/L 2-ME2 for 12 h, the expression of Bax protein was up-regulated, BCL-2 protein was down-regulated, caspase-3 protein expression was up-regulated, and C-myc protein expression was down-regulated, all of them showed a time-dependent relationship. CONCLUSION 2-ME2 shows obvious inhibitory effect on lymphoma Raji cells in a dose- and time-dependent manner. Its mechanism of treatment on lymphoma Raji cells may be related to up-regulation of Bax/BCL-2 ratio and activation of Caspase-3 to induce apoptosis in cancer cells. Down-regulation of C-myc protein expression also participates in the apoptotic process.
2-Methoxyestradiol ; Apoptosis ; Caspase 3/metabolism* ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Lymphoma ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Up-Regulation ; bcl-2-Associated X Protein

Glycoproteins isolated from fruit bodies and mycelial cultures of mushrooms exhibit anti-carcinogenic actions in human cancer cells and animal tumor cells by induction of apoptosis. Here, we report that isoflavone-conjugated glycoproteins (designate Gluvone), exhibit strong anti-carcinogenic effects on human breast cancer MCF-7 cells by induction of apoptosis. Gluvone with 9.4 kDa of molecular weight was isolated from submerged-liquid culture of Agaricus blazei mycelia (ABM) in soy flake-containing liquid medium. MCF-7 cells were incubated with various amounts of Gluvone (0~250 microM) for a period of 6 days. Gluvone exhibited anti-proliferative actions in a dose-dependent manner and 62% growth inhibition at 200 microM for 4 days relative to control. Hoechst 33258 staining analysis revealed that Gluvone induced formation of apoptotic bodies. Gluvone was associated with down-regulation of anti-apoptotic Bcl-2 protein expression as well as up-regulation of pro-apoptotic Bax protein expression. Gluvone treatment induced proteolytic activation of caspase-9 and caspase-3 through cytochrome c release from mitochondria to cytosol as well as concomitant degradation of poly (ADP-ribose) polymerase (PARP). In addition, Gluvone induced activation of caspase-8. Taken all together, these results indicate that the anti-proliferative effect of Gluvone is associated with induction of apoptotic cell death through the mitochondrial dysfunction pathway mediated by enhancement of Bax protein expression and suppression of Bcl-2 protein expression.
Agaricales ; Agaricus* ; Animals ; Anticarcinogenic Agents ; Apoptosis ; bcl-2-Associated X Protein* ; Bisbenzimidazole ; Breast Neoplasms ; Caspase 3 ; Caspase 8 ; Caspase 9 ; Cell Death ; Cytochromes c ; Cytosol ; Down-Regulation ; Fruit ; Glycoproteins* ; Humans ; Isoflavones* ; MCF-7 Cells ; Mitochondria ; Molecular Weight ; Up-Regulation