• Journal of Photoscience
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• v.9 no.2
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• pp.225-228
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• 2002

Bcl-2 is a member of large bcl-2 family and protects cells from apoptosis. Using bcl-2-expressing adenovirus vector (Ad-bc1-2), we investigated the effect of bc1-2 on UVB-induced apoptosis. Adenovirus vector efficiently introduced bc1-2 gene in cultured normal mouse keratinocytes (NMK cells); almost all NMK cells (lx10$^{6}$ ) were transfected at Ixl0$^{8}$ PFU/ml. Bcl-2-transfected NMK cells were significantly resistant to UVB-induced apoptosis with the suppressive effect dependent on bcl-2-expression level. Following UVB irradiation caspase 8, 3, 9 activities were stimulated in NMK cells, while in bc1-2-transfected cells, only caspase 8, but not caspase 3 or 9 activities were stimulated. In order to investigate the effect of bc1-2 in vivo, topical application of Ad-bc1-2 on tape-stripped mouse skin was performed. Following the application, Bc1-2 was efficiently overexpressed in almost all viable keratinocytes. The expression was transient with the maximal expression of Bc1-2 at 1st day following the application of lxl0$^{9}$ PFU in 200ml. The introduced Bc1-2 remained at least for 6 days. UVB irradiation (1250 J/m$^2$) induced apoptosis within 12 h and the maximal effect was observed at 24 h in control mouse skin. Bc1-2-transfected mice skin were resistant to UVB-induced apoptosis. Topical application of empty adenovirus vector alone had no effect on Bc1-2 expression or UVB-induced apoptosis. These results indicate that adenovirus vector is an efficient gene delivery system into keratinocytes and that Bcl-2 is a potent inhibitor of UVB-induced apoptosis both in vitro and in vivo.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.8-15
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• 2008

Saussurea lappa (SL) has been used to reduce abdominal pain and tenesmus in traditional oriental medicine. SL and major compounds of SL, sesquiterpene lactones, have been suggested to possess various biological effects, including anti-tumor, anti-ulcer, anti-inflammatory, anti-viral and cardiotonic activities. Recently, it has been reported that ethanol extracts from roots of SL have antiproliferative effects on gastric cancer cells. To explore the possibility that SL has chemopreventive effects on prostate cancer, we examined whether the hexane extract of SL (HESL) inhibits the growth of LNCaP human prostate cancer cells. Cells were incubated with various concentrations ($0{\sim}4$ mg/L) of HESL in DMEM/F12 containing 5% charcoal stripped fetal bovine serum. HESL substantially decreased viable cell numbers and induced apoptosis of LNCaP cells in dose-dependent manners. HESL increased the levels of cleaved caspase-8, -9, -7 and -3, and poly (ADP-ribose) polymerase. HESL increased the levels of the pro-apoptotic Bak and truncated-Bid proteins whereas it had no effect on the anti-apoptotic Bcl-2, Bcl-xL, or Mcl-1. The present results indicate that HESL inhibits the growth of human prostate cancer cells by inducing apoptosis, which involves the activation of the caspase cascades.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.153-162
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• 2001

Purpose : The mechanical insights of death of cancer cells by ionizing radiation are not of 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 pretenses, $Bcl_2/Bax$, 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 M 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 pretense 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 addiiton, 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, $Bcl_2/Bax$, Fas and Fas-L in a time and dose dependent manner.

• Radiation Oncology Journal
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• v.18 no.3
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• pp.214-219
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• 2000

Purpose : To Investigate the pathways of radiation induced apoptosls and the effect of cysteamine (${\beta}$-mercaptoethyiamine), as a radioprotector, on it. Materials and Methods : HL-50 ceils were assigned to control, irradiated, and cysteamlne (1 mM, 10mM) pretreated groups. Irradiation was given In a single fraction of 10 Gy (6 MV x-ray) and cysteamine was administered 1 hour before irradiation. The activities of caspase-8 were measured in control and irradiated group to evaluate its relation to the radiation Induced apoptosis. To evaluate the role of cysteamine In radiation Induced apoptosis, the number of viable cells, the expression and activity of caspase-3, and the expression of poly (ADP-ribose) polymerase (PARP) were measured and compared after irradiating the HL-60 celis with cysteamine pretreatment or not. Results : The intraceliular caspase-8 activity, known to be related to the death receptor induced apoptosis, was not affected by irradiation(p>0.05). The number of viable cells began to decrease from 6 hours after irradiation (p>0.05), but the number of viable cells In 1 mM cysteamine pretreated group was not decreased after irradiation and was similar to those in the control group. In caspase-3 analyses, known as apoptosis executioner, its expression was not different but its activity was Increased by irradiation(p>0.05). However, this Increase of activity was suppressed by the pretreatment of 1 mM cysteamine. The cleavage of PARP, thought to be resulted from caspase-3 activation, occurred after irradiation which was attenuated by the pretreatment of 1 mM cysteamine. Conclusion : These results show that radiation induced apoptotic process is somewhat different from death receptor induced one and the pretreatment of 1 mM cysteamine has a tendency to decrease the radiation-induced apoptosis in HL-60 cells.

• BMB Reports
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• v.47 no.8
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• pp.433-438
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• 2014

Plant sterols have shown potent anti-proliferative effects and apoptosis induction against breast and prostate cancers. However, the effect of sterols against hepatic cancer has not been investigated. In the present study, we assessed whether the stigmasterol isolated from Navicula incerta possesses apoptosis inductive effect in hepatocarcimona (HepG2) cells. According to the results, Stigmasterol has up-regulated the expression of pro-apoptotic gene expressions (Bax, p53) while down-regulating the anti-apoptotic genes (Bcl-2). Probably via mitochondrial apoptosis signaling pathway. With the induction of apoptosis caspase-8, 9 were activated. The DNA damage and increase in apoptotic cell numbers were observed through Hoechst staining, annexin V staining and cell cycle analysis. According to these results, we can suggest that the stigmasterol shows potent apoptosis inductive effects and has the potential to be tested as an anti-cancer therapeutic against liver cancer.

• Journal of Life Science
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• v.26 no.4
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• pp.431-438
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• 2016

The tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is considered a promising anticancer agent due to its unique ability to induce cancer cell death having only negligible effects on normal cells. However, many cancer cells tend to be resistant to TRAIL. In this study, we investigated the effects and molecular mechanisms of sodium butyrate (SB), a histone deacetylase inhibitor, in sensitizing TRAIL-induced apoptosis in 5637 human bladder cancer cells. Our results indicated that co-treatment with SB and TRAIL significantly increased the apoptosis induction, compared with treatment with either agent alone. Co-treatment with SB and TRAIL effectively increased the cell-surface expression of death receptor (DR) 5, but not DR4, which was associated with the inhibition of cellular Fas-associated death domain (FADD)-like interleukin-1β-converting enzyme (FLICE) inhibitory protein (c-FLIP). Furthermore, the activation of caspases (caspase-3, -8 and -9) and degradation of poly(ADP-ribose) were markedly increased in 5637 cells co-treated with SB and TRAIL; however, the synergistic effect was perfectly attenuated by caspase inhibitors. We also found that combined treatment with SB and TRAIL effectively induced the expression of pro-apoptotic Bax, cytosolic cytochrome c and cleave Bid to truncated Bid (tBid), along with down-regulation of anti-apoptotic Bcl-xL expression. These results collectively suggest that a combined regimen of SB plus TRAIL may offer an effective therapeutic strategy for safely and selectively treating TRAIL-resistant bladder cancer cells.

• International Journal of Oral Biology
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• v.45 no.3
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• pp.107-114
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• 2020

Acacetin, which is present in damiana (Turnera diffusa) and black locust (Robinia pseudoacacia), has several pharmacologic activities such as antioxidant, anti-inflammatory, and anti-proliferative effects on cancer cells. However, the effect of acacetin on head and neck cancers has not been clearly established. This study aimed to examine the effects of acacetin on cell growth and apoptosis induction in FaDu human pharyngeal carcinoma cells. These were investigated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay, Live/Dead cell assay, 4',6-diamidino-2-phenylindole dihydrochloride staining, caspase-3 and caspase-7 activation assay, and immunoblotting in FaDu cells. Acacetin induced FaDu cell death in a dose-dependent manner, with an estimated IC₅₀ value of 41.9 µM, without affecting the viability of L-929 mouse fibroblasts as normal cells. Acacetin treatment resulted in nuclear condensation in the FaDu cells. It promoted the proteolytic cleavage of procaspase-3, -7, -8, and -9 with increasing amounts of the cleaved caspase isoforms in FaDu cells. Acacetin-induced apoptosis in FaDu cells was mediated by the expression of Fas and activation of caspase-8, caspase-3, and poly (ADP-ribose) polymerase. Immunoblotting showed downregulation of the anti-apoptotic mitochondrial proteins Bcl-2 and Bcl-xL, but upregulation of the mitochondria-dependent pro-apoptotic proteins Bax and Badin FaDu cells after acacetin treatment. These findings indicate that acacetin inhibits cell proliferation and induces apoptotic cell death in FaDu human pharyngeal carcinoma cells via both the death receptor-mediated extrinsic apoptotic pathway and the mitochondria-mediated intrinsic apoptotic pathway.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8503-8512
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• 2016

The purpose of this study was to provide a detailed explanation of the mechanism of bisanthracycline, WP 631 in comparison to doxorubicin (DOX), a first generation anthracycline, currently the most widely used pharmaceutical in clinical oncology. Experiments were performed in SKOV-3 ovarian cancer cells which are otherwise resistant to standard drugs such as cis-platinum and adriamycin. As attention was focused on the ability of WP 631 to induce apoptosis, this was examined using a double staining method with Annexin V and propidium iodide probes, with measurement of the level of intracellular calcium ions and cytosolic cytochrome c. The western blotting technique was performed to confirm PARP cleavage. We also investigated the involvement of caspase activation and DNA degradation (comet assay and immunocytochemical detection of phosphorylated H2AX histones) in the development of apoptotic events. WP 631 demonstrated significantly higher effectiveness as a pro-apoptotic drug than DOX. This was evident in the higher levels of markers of apoptosis, such as the externalization of phosphatidylserine and the elevated level of cytochrome c. An extension of incubation time led to an increase in intracellular calcium levels after treatment with DOX. Lower changes in the calcium content were associated with the influence of WP 631. DOX led to the activation of all tested caspases, 8, 9 and 3, whereas WP 631 only induced an increase in caspase 8 activity after 24h of treatment and consequently led to the cleavage of PARP. The lack of active caspase 3 had no outcome on the single and double-stranded DNA breaks. The obtained results show that WP 631 was considerably more genotoxic towards the investigated cell line than DOX. This effect was especially visible after longer times of incubation. The above detailed studies indicate that WP 631 generates early apoptosis and cell death independent of caspase-3, detected at relatively late time points. The observed differences in the mechanisms of the action of WP631 and DOX suggest that this bisanthracycline can be an effective alternative in ovarian cancer treatment.

• Tuberculosis and Respiratory Diseases
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• v.71 no.2
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• pp.88-96
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• 2011

Background: It is known that cigarette smoke (CS) causes cell death. Apoptotic cell death is involved in the pathogenesis of CS-related lung diseases. Some members of the protein kinase C (PKC) family have roles in cigarette smoke extract (CSE)-induced apoptosis. This study was conducted to investigate the role of PKC epsilon in CSE-induced apoptosis in human lung fibroblast cell line, MRC-5. Methods: Lactate dehydrogenase release was measured using a cytotoxicity detection kit. The MTT assay was used to measure cell viability. Western immunoblot, Hoechst 33342 staining and flow cytometry were used to demonstrate the effect of $PKC{\varepsilon}$. Caspase-3 and caspase-8 activities were determined using a colorimetric assay. To examine $PKC{\varepsilon}$ activation, Western blotting was performed using both fractions of membrane and cytosol. Results: We showed that CSE activated $PKC{\varepsilon}$ by demonstrating increased expression of $PKC{\varepsilon}$ in the plasma membrane fraction. Pre-treatment of $PKC{\varepsilon}$ peptide inhibitor attenuated CSE-induced apoptotic cell death, as demonstrated by the MTT assay (13.03% of control, 85.66% of CSE-treatment, and 53.73% of $PKC{\varepsilon}$ peptide inhibitor-pre-treatment, respectively), Hoechst 33342 staining, and flow cytometry (85.64% of CSE-treatment, 53.73% of $PKC{\varepsilon}$ peptide inhibitor-pre-treatment). Pre-treatment of $PKC{\varepsilon}$ peptide inhibitor reduced caspase-3 expression and attenuated caspase-3, caspase-8 activity compared with CSE treatment alone. Conclusion: $PKC{\varepsilon}$ seem to have pro-apoptotic function and exerts its function through the extrinsic apoptotic pathway in CSE-exposed MRC-5 cells. This study suggests that $PKC{\varepsilon}$ inhibition may be a therapeutic strategy in CS-related lung disease such as chronic obstructive pulmonary disease.

• Journal of Life Science
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• v.25 no.5
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• pp.515-522
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• 2015

Treculia africana Decne, a breadfruit species, is native to many parts of West and Tropical Africa. The breadfruit belongs to the family Moraceae and is one of the four members of the genera Treculia. The crude extract of T. africana has been used in folk medicine as an anti-inflammatory agent for various ailments, such as whooping cough. In this study, we evaluated the anti-oxidative and anti-cancer activities of the methanol extract of T. africana Decne (META) and the molecular mechanisms of its anti-cancer effects in human colon carcinoma HT29 cells. The META exhibited anti-oxidative activity through a DPPH radical scavenging capacity and inhibited cell growth in a dose-dependent manner in HT29 cells. META treatment induced apoptosis of HT29 cells, showing an increase in the percentage of both SubG1 cells and Annexin V-positive cells and the formation of apoptotic bodies in a dose-dependent manner. META-mediated apoptosis was associated with the up-regulation of the death receptor FAS and Bax and a decrease in the Bcl-2 expression. META-treated HT29 cells also showed the release of cytochrome c from the mitochondria into the cytosol, activation of caspase-3, caspase-8, and caspase-9, and proteolytic cleavage of poly ADP-ribose polymerase (PARP). These findings suggest META may exert an anti-cancer effect in HT29 cells by inducing apoptosis through both intrinsic and extrinsic pathways.