• Journal of Chest Surgery
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• 제45권1호
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• pp.1-10
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• 2012

Background: ${\alpha}$-Lipoic acid (${\alpha}$-LA) has been studied as an anticancer agent as well as a therapeutic agent for diabetes and obesity. We performed this study to evaluate the anticancer effects and mechanisms of ${\alpha}$-LA in a lung cancer cell line, A549. Materials and Methods: ${\alpha}$-LA-induced apoptosis of A549 cells was detected by fluorescence-activated cell sorting analysis and a DNA fragmentation assay. Expression of apoptosis-related genes was analyzed by western blot and reverse transcription.polymerase chain reaction analyses. Results: ${\alpha}$-LA induced apoptosis and DNA fragmentation in A549 cells in a dose- and time-dependent manner. ${\alpha}$-LA increased caspase activity and the degradation of poly (ADP-ribose) polymerase. It induced expression of endoplasmic reticulum (ER) stress-related genes, such as glucose-regulated protein 78, C/EBP-homologous protein, and the short form of X-box binding protein-1, and decreased expression of the anti-apoptotic protein, X-linked inhibitor of apoptosis protein. Reactive oxygen species (ROS) production was induced by ${\alpha}$-LA, and the antioxidant N-acetyl-L-cysteine decreased the ${\alpha}$-LA-induced increase in expression of apoptosis and ER stress-related proteins. Conclusion: ${\alpha}$-LA induced ER stress-mediated apoptosis in A549 cells via ROS. ${\alpha}$-LA may therefore be clinically useful for treating lung cancer.

• 대한임상독성학회지
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• 제9권2호
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• pp.71-76
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• 2011

Purpose: The Rumack-Matthew nomogram cannot be applied in managing overdose by extended release (ER) preparation acetaminophen (AAP). This study analyzed the clinical characteristics of ER preparation AAP overdose in order to develop a treatment recommendation. Methods: We retrospectively reviewed the medical records of patients presented to the emergency department as a result of AAP overdose from Jan 2008 to Dec 2010. Only those patients who ingested an ER preparation of AAP were included in the study. Their blood AAP concentrations were measured at 4 and 8 hours after ingestion. Clinical variables related to AAP intoxication were analyzed. Results: Of the total 108 AAP overdose patients identified during the 3-year period, 20 suffered specifically with ER preparation AAP overdose. The mean estimated ingestion amount was 167.5 mg/kg. Treatments including gastric lavage, activated charcoal, and N-acetyl cysteine (NAC) were performed on 10, 14, and 11 patients, respectively. Hepatotoxicity was diagnosed in only one patient who was then successfully treated with NAC. In another case, blood AAP concentration continued to increase until at least 11-hours after ingestion. Conclusion: This study suggested that blood AAP concentrations associated with ingestion of ER formulations of AAP, may increase in an extended manner. Therefore, multiple sampling and longer periods between samples assessing AAP blood concentration may be required for incidences of extended release overdose.

• BMB Reports
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• 제53권11호
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• pp.576-581
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• 2020

Dimethylation of the histone H3 protein at lysine residue 9 (H3K9) is mediated by euchromatin histone methyltransferase II (EHMT2) and results in transcriptional repression of target genes. Recently, chemical inhibition of EHMT2 was shown to induce various physiological outcomes, including endoplasmic reticulum stress-associated genes transcription in cancer cells. To identify genes that are transcriptionally repressed by EHMT2 during apoptosis, and cell stress responses, we screened genes that are upregulated by BIX-01294, a chemical inhibitor of EHMT2. RNA sequencing analyses revealed 77 genes that were upregulated by BIX-01294 in all four hepatic cell carcinoma (HCC) cell lines. These included genes that have been implicated in apoptosis, the unfolded protein response (UPR), and others. Among these genes, the one encoding the stress-response protein Ras-related GTPase C (RRAGC) was upregulated in all BIX-01294-treated HCC cell lines. We confirmed the regulatory roles of EHMT2 in RRAGC expression in HCC cell lines using proteomic analyses, chromatin immune precipitation (ChIP) assay, and small guide RNA-mediated loss-of-function experiments. Upregulation of RRAGC was limited by the reactive oxygen species (ROS) scavenger N-acetyl cysteine (NAC), suggesting that ROS are involved in EHMT2-mediated transcriptional regulation of stress-response genes in HCC cells. Finally, combined treatment of cells with BIX-01294 and 5-Aza-cytidine induced greater upregulation of RRAGC protein expression. These findings suggest that EHMT2 suppresses expression of the RRAGC gene in a ROS-dependent manner and imply that EHMT2 is a key regulator of stress-responsive gene expression in liver cancer cells.

• BMB Reports
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• 제39권5호
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• pp.618-625
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• 2006

The infiltration of both monocyte and activated T cells in the skin is one of critical steps in the development of UVB-induced inflammation. Upregulation of adhesion molecules such as intercellular adhesion molecule 1 (ICAM-1) on the surface of keratinocytes plays an important role in this process. In this study, we examined the molecular mechanism responsible for UVB-induced expression of ICAM-1 and subsequent monocyte adhesion by keratinocyte. We observed that (1) UVB induced protein and mRNA expression of ICAM-1 in a dose- and time-dependent manner in human keratinocyte cell HaCaT; (2) UVB induced the translocation of NF-kappaB and inhibition of NF-kappaB by NF-kappaB inhibitors suppressed UVB-induced mRNA and protein expression of ICAM-1; (3) UVB increased the intracellular level of reactive oxygen species (ROS) by HaCaT cells; (4) UVB-induced increase of intracellular ROS level was suppressed by pre-treatment with diphenyl iodonium (DPI) and N-acetyl cysteine (NAC); and (5) inhibition of UVB-induced ROS production by DPI or NAC suppressed UVB-mediated translocation of NF-kappaB, expression of ICAM-1 and subsequent monocyte adhesion in HaCaT cells. These results suggest that UVB-induced ROS is involved in the translocation of NF-kappaB which is responsible for expression of ICAM-1 and subsequent increased monocyte adhesion in human keratinocyte.

• BMB Reports
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• 제46권9호
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• pp.460-464
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• 2013

The progression of androgenetic alopecia is closely related to androgen-inducible transforming growth factor (TGF)-${\beta}1$ secretion by hair follicle dermal papilla cells (DPCs) in bald scalp. Physiological levels of androgen exposure were reported to increase reactive oxygen species (ROS) generation. In this study, rat vibrissae dermal papilla cells (DP-6) transfected with androgen receptor showed increased ROS production following androgen treatment. We confirmed that TGF-${\beta}1$ secretion is increased by androgen treatment in DP-6, whereas androgen-inducible TGF-${\beta}1$ was significantly suppressed by the ROSscavenger, N-acetyl cysteine. Therefore, we suggest that induction of TGF-${\beta}1$ by androgen is mediated by ROS in hair follicle DPCs.

• Biomolecules & Therapeutics
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• 제24권5호
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• pp.510-516
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• 2016

Isoegomaketone (IK) was isolated from Perilla frutescens, which has been widely used as a food in Asian cuisine, and evaluated for its biological activity. We have already confirmed that IK induced the HO-1 expression via Nrf2 activation in RAW264.7 cells. In this study, we investigated the effect of IK on the mechanism of HO-1 expression. IK upregulated HO-1 mRNA and protein expression in a dose dependent manner. The level of HO-1 mRNA peaked at 4 h after $15{\mu}M$ IK treatment. To investigate the mechanisms of HO-1 expression modulation by IK, we used pharmacological inhibitors for the protein kinase C (PKC) family, PI3K, and p38 MAPK. IK-induced HO-1 mRNA expression was only suppressed by SB203580, a specific inhibitor of p38 MAPK. ROS scavengers (N-acetyl-L-cysteine, NAC, and glutathione, GSH) also blocked the IK-induced ROS production and HO-1 expression. Furthermore, both NAC and SB203580 suppressed the IK-induced Nrf2 activation. In addition, ROS scavengers suppressed other oxidative enzymes such as catalase (CAT), glutathione S-transferase (GST), and NADH quinone oxidoreductase (NQO-1) in IK-treated RAW264.7 cells. Taken together, it can be concluded that IK induced the HO-1 expression through the ROS/p38 MAPK/Nrf2 pathway in RAW264.7 cells.

• Asian Pacific Journal of Cancer Prevention
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• 제15권17호
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• pp.7291-7296
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• 2014

Different plant parts of Flacourtia indica have long been used in Ayurvedic medicine. Previous studies have demonstrated that the methanolic extract of F. indica possess anti-inflammatory properties. The present study was aimed at investigating the anticancer effects of methanol extract of Flacourtia indica (FIM) aerial parts in human colon cancer (HCT116) cells. Treatment of cells with FIM at a concentration of $500{\mu}g/ml$ for 24 hours significantly reduced cell viability and induced apoptosis, which was associated with the increased cytoplasmic expression of cytochrome c, activation of caspase-3, and the cleavage of poly-(ADP-ribose) polymerase. Incubation with FIM also inhibited the levels of Bcl-2, Bcl-xl and survivin, which are the markers of cell proliferation, whereas the expression of Bax remained unchanged. Treatment with FIM led to the generation of reactive oxygen species (ROS) in a concentration-dependent manner. Pharmacological inhibition of ROS generation by pretreatment of cells with N-acetyl cysteine abrogated FIM-induced apoptosis in HCT116 cells. Thus, these results demonstrate that FIM has anti-proliferative and pro-apoptotic effects in HCT116 cells and the effects are, at least in part, due to the ROS dependent activation of caspases.

• 동의생리병리학회지
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• 제22권5호
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• pp.1140-1146
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• 2008

One of the major side effects of cisplatin is nephrotoxicity, leading to acute renal failure. Recent study has suggested a role of hydroxyl radicals and p53 in renal cell injury by cisplatin. This study determined the possible involvement of oxidative stress in p53 activation. In rat mesangial cells, cisplatin treatment induced apoptosis and p53 activation. Pifithrin-$\alpha$, a pharmacological inhibitor of p53, suppressed cisplatin-induced apoptosis. Cisplatin also induced reactive oxidative species (ROS) generation. Of interest, cisplatin-induced apoptosis was prevented by N-acetyl-cysteine (NAC), a general antioxidant. NAC diminished p53 activation during cisplatin treatment. Puerariae Radix and Rehmanniae Radix Preparata with antioxidative activity were reduced the cisplatin-induced ROS generation, caspase-3 activity and p53 activation. In conclusion, ROS may contribute to p53 activation to initiate cisplatin-induced apoptosis in rat mesangial cells. In result, antioxidative effect of Puerariae Radix and Rehmanniae Radix Preparata prevented cisplatin-induced apoptosis through inhibition of p53 activation.

• Molecules and Cells
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• 제42권12호
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• pp.884-892
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• 2019

Piperlongumine (PL), a natural alkaloid compound isolated from long pepper (Piper longum), can selectively kill cancer cells, but not normal cells, by accumulation of reactive oxygen species (ROS). The objective of this study was to investigate functional roles of expression of SETDB1 and FosB during PL treatment in MCF7 breast cancer cells. PL downregulates SETDB1 expression, and decreased SETDB1 expression enhanced caspase 9 dependent-PARP cleavage during PL-induced cell death. PL treatment generated ROS. ROS inhibitor NAC (N-acetyl cysteine) recovered SETDB1 expression decreased by PL. Decreased SETDB1 expression induced transcriptional activity of FosB during PL treatment. PARP cleavage and positive annexin V level were increased during PL treatment with FosB overexpression whereas PARP cleavage and positive annexin V level were decreased during PL treatment with siFosB transfection, implying that FosB might be a pro-apoptotic protein for induction of cell death in PL-treated MCF7 breast cancer cells. PL induced cell death in A549 lung cancer cells, but molecular changes involved in the induction of these cell deaths might be different. These results suggest that SETDB1 mediated FosB expression may induce cell death in PL-treated MCF7 breast cancer cells.

• 대한약침학회지
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• 제18권3호
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• pp.32-41
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• 2015

Objectives: Condurango (Gonolobus condurango) extract is used by complementary and alternative medicine (CAM) practitioners as a traditional medicine, including homeopathy, mainly for the treatment of syphilis. Condurango bark extract is also known to reduce tumor volume, but the underlying molecular mechanisms still remain unclear. Methods: Using a cervical cancer cell line (HeLa) as our model, the molecular events behind condurango extract's (CE's) anticancer effect were investigated by using flow cytometry, immunoblotting and reverse transcriptase-polymerase chain reaction (RT-PCR). Other included cell types were prostate cancer cells (PC3), transformed liver cells (WRL-68), and peripheral blood mononuclear cells (PBMCs). Results: Condurango extract (CE) was found to be cytotoxic against target cells, and this was significantly deactivated in the presence of N-acetyl cysteine (NAC), a scavenger of reactive oxygen species (ROS), suggesting that its action could be mediated through ROS generation. CE caused an increase in the HeLa cell population containing deoxyribonucleic acid (DNA) damage at the G zero/Growth 1 (G0/G1) stage. Further, CE increased the tumor necrosis factor alpha ($TNF-{\alpha}$) and the fas receptor (FasR) levels both at the ribonucleic acid (RNA) and the protein levels, indicating that CE might have a cytotoxic mechanism of action. CE also triggered a sharp decrease in the expression of nuclear factor kappa-light-chain-enhancer of activated B cells ($NF-{\kappa}B$) both at the RNA and the protein levels, a possible route to attenuation of B-cell lymphoma 2 (Bcl-2), and caused an opening of the mitochondrial membrane's permeability transition (MPT) pores, thus enhancing caspase activities. Conclusion: Overall, our results suggest possible pathways for CE mediated cytotoxicity in model cancer cells.