• Korean Journal of Plant Resources
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• v.32 no.4
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• pp.255-263
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• 2019

Glycyrrhizae radix is one of the most frequently prescribed ingredients in Oriental medicine, and Glycyrrhizae radix extract has been shown to exert anti-cancer effects. However, the cellular and molecular mechanisms of programed cell death (apoptosis) by Glycyrrhizae radix are poorly defined. In the present study, it was examined the molecular mechanisms of apoptosis by water extracts of Glycyrrhizae radix (GRW) in human bladder T24 cancer cells. It was found that GRW could inhibit the cell growth of T24 cells in a concentration-dependent manner, which was associated with the induction of apoptotic cell death, as evidenced by the formation of apoptotic bodies, DNA fragmentation and increased populations of annexin-V positive cells. The induction of apoptotic cell death by GRW was connected with an up-regulation of pro-apoptotic Bax protein expression and down-regulation of anti-apoptotic proteins (Bcl-2 and Bcl-xL), and inhibition of apoptosis family proteins (XIAP, cIAP-1 and cIAP-2). In addition, apoptosis-inducing concentrations of GRW induced the activation of caspase-9, an initiator caspase of the mitochondrial-mediated intrinsic pathway, and caspase-3, accompanied by proteolytic degradation of PARP. GRW also induced apoptosis via a death receptor-mediated extrinsic pathway by caspase-8 activation, resulting in the down-regulation of total Bid and suggesting the existence of cross-talk between the extrinsic and intrinsic pathways. Taken together, the present results suggest that GRW may be a potential chemotherapeutic agent for the control of human bladder cancer cells.

• Archives of Pharmacal Research
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• v.26 no.5
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• pp.405-410
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• 2003

Vitamin K-related analogs induce growth inhibition in various cancer cell lines. A naphthoquinone analog, termed 2,3-dichloro-5, 8-dihydroxy-1,4-naphthoquinone (DDN), induces apoptosis in human promyeloid leukemic HL-60 cells, and shows antitumor activity in vivo. Following treatment with DDN, evidence of apoptosis, including DNA fragmentation and cleavage of poly ADP ribose polymerase (PARP), was observed. DDN induced an upregulation of proapoptotic Bax protein, and Bid cleavage. Antiapoptotic Bcl-2 protein levels were not changed by DDN, but the expression of Bcl-xL was decreased. In addition, DDN reduced the mass of solid tumor in the Sarcoma 180 tumor-bearing mouse model. These results indicate that DDN exerts antitumor activity, which appears to be related to the induction of apoptosis by regulating Bcl-2 family proteins.

• BMB Reports
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• v.54 no.3
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• pp.176-181
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• 2021

Bcl-x, a member of the Bcl-2 family, plays a key role in apoptosis. Alternative splicing of Bcl-x pre-mRNA through alternative 5' splice-site selection produces an anti-apoptotic mRNA isoform that includes exon 2b and a pro-apoptotic Bcl-x mRNA isoform that excludes exon 2b. Here we used Bcl-x minigene and identified SRSF2 and SRSF6 as two regulatory factors of 5' splice-site selection of Bcl-x pre-mRNA. We selected binding clusters closer to 5' splice-sites from multiple potential binding sites of SRSF2 and SRSF6 to perform loss of functions analysis through site-directed mutagenesis. Our results demonstrated that these mutations did not abolish regulatory functions of SRSF2 or SRSF6, indicating that a single binding motif or a cluster was not a functional target of these proteins in Bcl-x pre-mRNA splicing. Random deletion mutagenesis did not disrupt the role of SRSF2 and SRSF6. Importantly, mutagenesis of 5' splice-site to a conserved or a weaker score demonstrated that the weaker strength of the target 5' splice-site or higher strength of the other 5' splice-site strength limited the role of SRSF2 and SRSF6 in 5' splice-site activation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.3
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• pp.759-766
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• 2004

In the present study, we investigated the effects of aqueous extract of the healthful decoction utilizing Phellinus linteus (HDPL) on the cell growth of human lung carcinoma tumor cell line A549. Exposure of A549 cells to HDPL resulted in growth inhibition and induction of apoptosis in a dose-dependent manner as measured by hemocytometer counts, fluorescence microscopy and flow cytometric analysis. This increase in apoptosis was associated with inhibition and/or degradation of apoptotic target proteins such as poly(ADP-ribose) polymerase (PARP), b-catenin and phospholipase C- 1 (PLC- 1) protein. HDPL treatment induced the down-regulation of anti-apoptotic Bcl-2 expression, an anti-apoptotic gene, however, the level of Bax. a pro-apoptotic gene, was increased by HDPL treatment. In addition, HDPL-induced apoptotis of A549 cells was connected with activation of caspase-3 and caspase-9 protease in a dose-dependent manner, however, the levels of inhibitor of apoptosis proteins family were remained unchanged. Taken together, these results indicated that the anti-proliferative effects of HDPL were associated with the induction of apoptotic cell death through regulation of several major growth regulatory gene products such as Bcl-2 family expression and caspase protease activity, and HDPL may have therapeutic potential in human lung cancer.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.1
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• pp.43-50
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• 2013

Palmitic acid (PAM), one of the most common saturated fatty acid (SFA) in animals and plants, has been shown to induce apoptosis in exocrine pancreatic AR42J cells. In this study, we investigated cellular mechanisms underlying protective effects of oleic acid (OLA) against the lipotoxic actions of PAM in AR42J cells. Exposure of cells to long-chain SFA induced apoptotic cell death determined by MTT cell viability assay and Hoechst staining. Co-treatment of OLA with PAM markedly protected cells against PAM-induced apoptosis. OLA significantly attenuated the PAM-induced increase in the levels of pro-apoptotic Bak protein, cleaved forms of apoptotic proteins (caspase-3, PARP). On the contrary, OLA restored the decreased levels of anti-apoptotic Bcl-2 family proteins (Bcl-2, Bcl-xL, and Mcl-1) in PAM-treated cells. OLA also induced up-regulation of the mRNA expression of Dgat2 and Cpt1 genes which are involved in triacylglycerol (TAG) synthesis and mitochondrial ${\beta}$-oxidation, respectively. Intracellular TAG accumulation was increased by OLA supplementation in accordance with enhanced expression of Dgat2 gene. These results indicate that restoration of anti-apoptotic/pro-apop-totic protein balance from apoptosis toward cell survival is involved in the cytoprotective effects of OLA against PAM-induced apoptosis in pancreatic AR42J cells. In addition, OLA-induced increase in TAG accumulation and up-regulation of Dgat2 and Cpt1 gene expressions may be possibly associated in part with the ability of OLA to protect cells from deleterious actions of PAM.

• Development and Reproduction
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• v.14 no.2
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• pp.83-89
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• 2010

Apoptosis is a crucial mechanism for the proper regulation of homeostasis. BCL-2 family proteins are key molecules which control cellular survival and apoptosis. MCL-1 (myeloid cell leukemia-1) is a pro-survival member of BCL-2 family that promotes the survival of cells, and is highly expressed in diverse cancers including ovarian cancer, leukemia, and cervical cancer. Previously we identified IEX-1 (immediate early response gene X-1) as a binding partner of MCL-1. In the present study, we demonstrated that overexpression of IEX-1 induced apoptosis of ovarian cancer cells. Moreover, IEX-1 significantly attenuated the pro-survival function of MCL-1 in these cells. Also, IEX-1-induced cell death activity was able to be modulated by changes in the expression level of MCL-1. Thus, these results suggest that both IEX-1 and MCL-1 modulate each other's function controlling cellular survival and death and the inhibitory activity of IEX-1 toward MCL-1 may be applied for the development of chemotherapeutics.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.1
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• pp.71-77
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• 2011

Gastric ulcer has multifactorial etiology, and the development of ulcer is known to be caused by gastric acidity, pepsin secretion, gastric motility and gastric mucosal blood flow. The ulcer results from the tissue necrosis and apoptotic cell death triggered by mucosal ischemia, free radical formation and cessation of nutrient delivery. The gastric mucosa is usually exposed to a wide range of aggressive insults, and has developed efficient mechanisms to repair tissue injury. The apoptotic process of gastric mucosa is triggered by the induction of such proapoptotic gene expression, such as BAX. The Bcl-2 family of proteins plays a pivotal role in the regulation of apoptosis. The maintenance of gastric mucosa integrity depends upon the ratio between cell proliferation and cell death. Stress-inducing factors may affect Bcl-2/BAX ratio and thus the rate of apoptosis through modulation of the expression of both proteins depends upon the experimental model. In addition to the regulation of apoptosis, new vessels have to be generated in order to ensure an adequate supply of oxygen and nutrients to the healing gastric mucosa. This events are regulated by several factors. Among them, such polypeptide growth factors, such as vascular endothelial growth factor (VEGF) regulates essential cell functions involved in tissue healing including cell proliferation and differentiation. The purpose of this study was carried to investigate whether Rhei Rhizoma administration might protect apoptotic cell death and promote angiogenesis in gastric mucosa. Sprague-Dawley rats were randomly divided into 4 groups; normal, saline, cimetidine and Rhei Rhizoma-treated group. The saline, cimetidine and Rhei Rhizoma extracts were orally administrated to each group and gastric ulcer was induced by HCl-EtOH solution. After 1 hour, the stomachs were collected for histological observation and immunohistochemistry. In results, Rhei Rhizoma proves to promote to heal wound in gastric ulcer in conclusion and the significant changes of BAX, Bcl-2 and VEGF quantity in gastric mucosa were observed. These results suggest that Rhei Rhizoma extract may promote incision wound healing and has protective effects on gastric ulcer in rats.

• Biomedical Science Letters
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• v.17 no.3
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• pp.177-184
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• 2011

Potassium cyanate (KOCN) is an inorganic compound and induces the carbamylation of proteins with cytotoxic effects on human cells. Although there is a potential cytotoxic molecule, the role of KOCN on the apoptosis of cancer cell is not well understood. The present study investigated the effects of KOCN on the human colorectal cancer cell line, HCT 116 cells. To understand the anti-cancer effect of KOCN on HCT 116 cells, we examined alteration of apoptosis, the intracellular $Ca^{2+}$ concentration, the intracellular signaling pathway and generation of reactive oxygen species (ROS) in these cells treated with KOCN. The apoptosis of HCT 116 cells was induced by KOCN in a dose-dependent manner at 24 hours and 48 hours, respectively. The apoptosis was processed via the cleavage of poly ADP-ribose polymerase (PARP) and activation of caspase 3 in HCT 116 cells. KOCN induced the elevation of intracellular $Ca^{2+}$ concentration and changed the expressions of Bcl-2 family proteins. The pro-apoptotic Bax was continuously up-regulated, and the anti-apoptotic Bcl-2 was down-regulated by KOCN. KOCN also induced the hyperpolarization of mitochondria and the generation of ROS in HCT 116 cells. Taken together, these results indicate that KOCN induces the apoptosis of HCT 116 cells by disruption of $Ca^{2+}$ homeostasis and via mitochondrial pathway. This study provides the compound that may be used as a potent agent for the treatment of colorectal cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3131-3138
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• 2016

Several studies have addressed the possible role of hepatitis C virus genotype-4 (HCV GT4) in apoptosis. However, this still not fully understood. In the current study a re-constructed clone of E1/E2 polyprotein region of the HCV GT4 was transfected into the Huh7 cell line and a human apoptotic PCR array of 84 genes was used to investigate its possible significance for apoptosis. Out of the 84 genes, only 35 showed significant differential expression, 12 genes being up-regulated and 23 down-regulated. The highest-up regulated genes were APAF1 (apoptotic peptidase-activating factor 1), BID (BH3 interacting domain death agonist) and BCL 10 (B-cell CLL/lymphoma protein 10) with fold regulation of 33.2, 30.1 and 18.9, respectively. The most down-regulated were FAS (TNF receptor super family), TNFRSF10B (tumor necrosis factor receptor super-family member 10b) and FADD (FAS-associated death domain) with fold regulation of -30.2, -27.7 and -14.9, respectively. These results suggest that the E1/E2 proteins may be involved in HCV-induced pathogenesis by modulating apoptosis through the induction of the intrinsic apoptosis pathway and disruption of the BCL2 gene family.

• YAKHAK HOEJI
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• v.45 no.4
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• pp.426-430
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• 2001

Cells are eliminated in a variety of physiological settings by apoptosis, a genetically encoded process of cellular suicide. Bak, a member of the Bcl-2 protein family, accelerates apoptosis by an unknown mechanism. We have found a novel cDNA encoding a 101 amino acid protein possessing a Bak-like in our full-length cDNA bank. Bak-like shares the conserved domains BHI and 2 with other proapoptotic proteins but lacks the BH3 domain. Bak-like is expressed in a wide variety of tissues. Like Bak, Bak-like gene product primarily enhances apoptotic cell death following an appropriate stimulus.