• Proceedings of the Korean Society of Applied Pharmacology
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• 2002.07a
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• pp.89-96
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• 2002

The importance of apoptosis in normal development and pathogenesis has been well recognized, and explosive progress towards dissecting its commitment step has been made during the past decade. Mitochondria, Apaf-1, caspase, and bcl-2 family members play central roles in the commitment step. However, it is still unclear how upstream cell survival pathways regulate apoptosis. It is also unknown whether the bcl-2 family members have any effect on the upstream survival pathways. We have demonstrated that the anti-apoptotic gene product bcl-2 greatly induces expression of the tissue inhibitor of metalloproteinase-1 (TIMP-1) in human breast epithelial cells. Surprisingly, we found that TIMP-1, like bcl-2, is a potent inhibitor of apoptosis induced by a variety of stimuli. Functional studies indicate that TIMP-1 inhibits a classical apoptotic pathway mediated by caspases, and that focal adhesion kinase (FAK)/Pl 3-kinase and mitogen activated protein kinase (MAPK) are critical for TIMP- 1 -mediated cell survival. We also showed specific association of TIMP-1 with the cell surface. Consistently, a 150-H)a surface protein was identified in MCF10A cells that specifically binds TIMP-1. Taken together, we hypothesize that TIMP-I binding on the cell surface induces a cell survival pathway that regulates the common apoptosis commitment step. The results of these studies will address a new paradigm in the regulation of apoptosis by an extracellular molecule TIMP-1, and also greatly enhance our understanding of TIMP-1's pleiotropic activity in many physiological and pathological processes. This information may also be useful in designing more rational therapeutic interventions aimed at modulating the anti-apoptotic activity of TIMP-1 .

• Journal of Physiology & Pathology in Korean Medicine
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• v.30 no.3
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• pp.150-156
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• 2016

Extract of Broussometia kazinoki Rhizodermatis has been traditionally used for geopoong, diuresis, hwalhyeol. In the present study, the apoptotic effect of methanol extract of Broussometia kazinoki (MBK) were investigated. Cell viability of A549 cells was measured by MTT assay. Apoptosis-related protein and MAPK protein levels were measured by Western blot. Chromatin condensation of A549 cells was stained with DAPI. MBK inhibited cell proliferation of A549 cell. Based on DAPI staining, MBK-treated cells manifested nuclear shrinkage, condensation and fragmentation. Treatment of A549 cells with MBK resulted in activation of the caspase-3, -8, -9 and cleavage of poly ADP-ribose polymerase (PARP). In the upstream, MBK increased the expressions Bax and Bak, decreased the expression of Bcl-2, and augmented the Bax/Bcl-2 ratio. MBK-induced apoptosis was accompanied by sustained phosphorylation of JNK, p38 MAPK and apoptosis signal-regulating kinase (ASK)-1. These results suggest that MBK induced apoptosis in A549 cells through Bcl-2 family protein-mediated mitochondria/caspase-3 dependent pathway. In addition, MBK increased the activation of ASK-1, which are critical upsteam signals for JNK/p38 MAPK activation in A549 cancer cells.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.4
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• pp.442-450
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• 2009

Piperine is an alkaloid-amine found in pepper and has been reported to have anticarcinogenic properties. To explore the possibility that piperine has cancer chemopreventive and chemotherapeutic effects in colon cancer, we examined whether piperine inhibits the growth of HT-29 human colon cancer cells and investigated the mechanisms for this effect. Cells were cultured with various concentrations ($0{\sim}40{\mu}M$) of piperine. Piperine decreased the cell viability and induced apoptosis of HT-29 cells. Western blot analysis of total cell lysates revealed that piperine decreases the protein levels of Bcl-2, Mcl-1, and intact Bid but increases Bik levels. Piperine increased the percentage of cells with depolarized mitochondrial membrane, and the release of cytochrome c into cytoplasm. Piperine induced the cleavage of poly (ADP-ribose) polymerase and caspases 8, 9, 7, and 3 and increased the Fas levels. In addition, piperine significantly decreased the protein levels of survivin. The present results indicate that piperine inhibits the growth of HT-29 colon cancer cells by the induction of apoptosis, which may be mediated by its ability to change the Bcl-2 family proteins, increase the activation of caspases, and decrease survivin levels. Overall, our findings suggest that piperine has cancer chemotherapeutic effects in colon cancer.

• BMB Reports
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• v.36 no.3
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• pp.269-274
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• 2003

In the fight against cancer, novel chemotherapeutic agents are constantly being sought to complement existing drugs. Various studies have presented evidence that the apoptosis that is induced by these anticancer agents is implicated in tumor regression, and Bcl-2 family genes play a part in apoptosis following treatment with various stimuli. Here, we present data that a styrylpyrone derivative (SPD) that is extracted from the plant Goniothalamus sp. showed cytotoxic effects on the human breast cancer cell line MCF-7. SPD significantly increased apoptosis in MCF-7 cells, as visualized by phase contrast microscopy and evaluated by the Tdt-mediated dUTP nick end-labeling assay and nuclear morphology. Western blotting and immunostaining revealed up-regulation of the proapoptotic Bax protein expression. SPD, however, did not affect the expression of the anti-apoptotic protein, Bcl-2. These results, therefore, suggest SPD as a potent cytotoxic agent on MCF-7 cells by inducing apoptosis through the modulation of Bax levels.

• BMB Reports
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• v.51 no.2
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• pp.92-97
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• 2018

B cell leukemia/lymphoma 3 (Bcl3) plays a pivotal role in immune homeostasis, cellular proliferation, and cell survival, as a co-activator or co-repressor of transcription of the $NF-{\kappa}B$ family. Recently, it was reported that Bcl3 positively regulates pluripotency genes, including Oct4, in mouse embryonic stem cells (mESCs). However, the role of Bcl3 in the maintenance of pluripotency and self-renewal activity is not fully established. Here, we report the dynamic regulation of the proliferation, pluripotency, and self-renewal of mESCs by Bcl3 via an influence on Nanog transcriptional activity. Bcl3 expression is predominantly observed in immature mESCs, but significantly decreased during cell differentiation by LIF depletion and in mESC-derived EBs. Importantly, the knockdown of Bcl3 resulted in the loss of self-renewal ability and decreased cell proliferation. Similarly, the ectopic expression of Bcl3 also resulted in a significant reduction of proliferation, and the self-renewal of mESCs was demonstrated by alkaline phosphatase staining and clonogenic single cell-derived colony assay. We further examined that Bcl3-mediated regulation of Nanog transcriptional activity in mESCs, which indicated that Bcl3 acts as a transcriptional repressor of Nanog expression in mESCs. In conclusion, we demonstrated that a sufficient concentration of Bcl3 in mESCs plays a critical role in the maintenance of pluripotency and the self-renewal of mESCs via the regulation of Nanog transcriptional activity.

• BMB Reports
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• v.45 no.8
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• pp.464-469
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• 2012

Endothelial cells (ECs) apoptosis induced by oxidized low-density lipoprotein (ox-LDL) is thought to play a critical role in atherosclerosis. MicroRNAs (miRNAs) are a class of noncoding RNAs that posttranscriptionally regulate the expression of genes involved in diverse cell functions, including differentiation, growth, proliferation, and apoptosis. MiRNA let-7 family is known to be involved in the regulation of cell apoptosis. However, the function of let-7 in ox-LDL induced ECs apoptosis and atherosclerosis is still unknown. Here, we show that let-7c expression was markedly up-regulated in ox-LDL induced apoptotic human umbilical cord vein endothelial cells (HUVECs). Let-7c over-expression enhanced apoptosis in ECs whereas inhibition of let-7c could partly alleviate apoptotic cell death mediated by ox-LDL. Searching for how let-7c affected apoptosis, we discovered that antiapoptotic protein Bcl-xl was a direct target of let-7c in ECs. Our data suggest that let-7c contributes to endothelial apoptosis through suppression of Bcl-xl.

• The Journal of Korean Obstetrics and Gynecology
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• v.24 no.2
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• pp.33-51
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• 2011

Objectives: This study was performed to assess the protective effect of Saengmaek-san (SM) on UVB-induced HaCaT cell damage. Methods: The protective effects of Saengmaek-san(SM) were determined by UVB-induced HaCaT assay. We assessed protective effects of Saengmaek-san (SM) on LDH release and nitrite release from HaCaT. And COX-2, Bcl-2, Bax, $TNF{\alpha}$, c-jun, c-fos, NF-kB, iNOS, Bcl-xL gene expression were determined in HaCaT using real-time PCR method. Results: 1. SM inhibited LDH-release, nitrite production in UVB-exposed HaCaT. 2. SM suppressed the gene expression of COX-2, $TNF{\alpha}$ in UVB-exposed HaCaT. 3. SM increased the gene expression of Bcl-2, Bax, Bcl-xL family protein in UVB-exposed HaCaT. 4. SM suppressed the gene expression of c-jun, c-fos, NF-kB in UVB-exposed HaCaT. Conclusions: The study showed SM inhibited the cell damage in UVB-exposed HaCaT.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1590-1598
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• 2008

Cell proliferation and differentiation are critical processes in a developing fetal rat brain, during which programmed cell death (PCD) also plays an important role. One of the decisive factors for PCD is Bcl-2 family proteins, where Bax induces cell death, whereas Bcl-2 acts as an inhibitor of PCD. As maternal drinking is known to cause fetal alcohol syndrome (FAS) or malformation of the fetal brain during pregnancy, the objective of the present study was to investigate whether maternal ethanol exposure alters the PCD-related Bax and Bcl-2 protein expression during fetal brain development. Pregnant female rats were orally treated with 10% ethanol and the subsequent expressions of the Bax and Bcl-2 proteins examined in the fetal brain, including the forebrain, midbrain, and hindbrain, from gestational day (GD) 15.5 to GD 19.5, using Western blots, in situ hybridization, and immunohistochemistry. With regard to the ratio of Bcl-2 to Bax proteins (Bcl-2/Bax), the Bax protein was dominant in the forebrain and midbrain of the control GD 15.5 fetuses, except for the hindbrain, when compared with the respective ethanol-treated groups. Moreover, Bcl-2 became dominant in the midbrain of the control GD 17.5 fetuses when compared with the ethanol-treated group, representing an alternation of the natural PCD process by ethanol. Furthermore, a differential expression of the Bcl-2 and Bax proteins was found in the differentiating and migrating zones of the cortex, hippocampus, thalamus, and cerebellum. Thus, when taken together, the present results suggest that ethanol affects PCD in the cell differentiation and migration zones of the prenatal rat brain by modulating Bax and Bcl-2 expression in an age- and area-dependent manner. Therefore, this is the first evidence that ethanol may alter FAS-associated embryonic brain development through the alteration of Bax and Bc1-2 expression.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.9
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• pp.1114-1119
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• 2008

Among the numerous polyphenols isolated from green tea, epigallocatechin gallate (EGCG) is a predominate and is considered to be a major therapeutic agent. To elucidate the mechanical insights of anti-tumor effect, EGCG was applied to human breast cancer MDA-MB-231 cells. We investigated the effect of EGCG on protein and mRNA expression of proteins related to cell apoptosis in MDA-MB-231 human breast cancer cell lines. We also identified caspase-3 activity. We cultured MDA-MB-231 cells in the presence of 0, 5, 10, and $20\;{\mu}M$ of EGCG. Protein and mRNA expression of bcl-2 were decreased dose-dependently in cells treated with EGCG. However, protein and mRNA expression of bax were increased (p<0.05). Caspase-3 activities were increased dose-dependently in cells treated with EGCG. These results suggest that EGCG induces cell apoptosis by increase of caspase activity through decreasing of protein and mRNA expression of bcl-2 and increasing of protein and mRNA expression of bax.