• Tuberculosis and Respiratory Diseases
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• 제54권5호
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• pp.495-509
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• 2003

연구배경 : 호중구에 의해 매개되는 염증반응은 호중구의 수명이 매우 짧기 때문에 대부분 자연 종결된다. 패혈증에서는 이러한 호중구의 아포프토시스가 감소되어 수명이 연장되어 있어서 지속적인 염증반응이 일어나게 된다. 호중구의 수명 연장을 유도하는 많은 염증 매개 물질들이 nuclear factor-${\kappa}B$ 전사인자에 의해 조절되기 때문에 이 연구에서는 nuclear factor-${\kappa}B$가 패혈증 환자에서 관찰되는 호중 구의 아포프토시스 억제와 연관이 있을 것으로 가정하였다. 방법 : 건강한 정상인과 패혈증 환자의 호중구를 정맥혈로부터 신선하게 분리하여 실험하였다. 호중구의 아포프토시스는 특징적인 아포프토시스의 형태를 보이는 세포를 광학현미경으로 세거나 Annexin V를 이용한 유세포분석법으로 정량하였다. Nuclear factor-${\kappa}B$의 활성도는 면역형광 엽색법 또는 electrophoretic mobility shift assay로 판단하였다. 항아포프토시스 단백인 X-linked inhibitor of apoptosis의 발현 정도는 western blot으로 평가하였다. 결과 : 패혈증 환자에서 자발적 아포프토시스가 감소되어 있음을 확인하였다. 패혈증 환자의 호중구에 cycloheximide를 처치하였을 때 아포프토시스가 유의하게 증가하여 아포프토시스 감소가 새로운 단백 합성에 의존적임을 관찰하였다. 패혈증 환자의 호중구에서는 정상인과는 달리 기저상태에서도 nuclear factor-${\kappa}B$가 핵 내로 이동되어 활성화되어 있었고 nuclear factor-${\kappa}B$의 활성을 억제하였을 때 아포프토시스의 억제가 반전되었다. 또한 nuclear factor-${\kappa}B$에 의존적인 X-linked inhibitor of apoptosis 단백의 발현 수준이 정상인의 호중구에서는 24시간 동안 배양하면서 점차 감소하였지만 패혈증 환자의 호중구에서는 지속적으로 발현 수준이 유지되었다. 결론 : 패혈증 환자에서 관찰되는 호중구의 아포프토시스 억제에는 nuclear factor-${\kappa}B$ 전사인자의 활성화에 의한 생존 단백의 유도가 관여할 것으로 생각하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권4호
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• pp.1471-1476
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• 2012

Background and Aim: Currently available systemic therapies for malignant melanoma produce low response rates in patients, and more effective treatment modalities are clearly needed. The tumor necrosis factor (TNF)-related apoptosis-inducing ligand has a significant impact on therapy for patients with X-linked inhibitor of apoptosis protein-downregulation malignant melanoma. The primary objective of this study was to assess its therapeutic potential. Materials and Methods: We employed a conditionally replicating oncolytic adenoviral vector, named CRAd5.TRAIL/siXIAP, with the characteristics of over-expression of the therapeutic gene TRAIL and downregulation of XIAP in one vector. B16F10-luc cells were employed to detect anti-tumor activity of CRAd5.TRAIL/siXIAP in vitro and in vivo. Results: CRAd5.TRAIL/siXIAP enhanced caspase-8 activation and caspase-3 maturation in B16F10 cells in vitro. Furthermore, it more effectively infected and killed melanoma cells in vitro and in vivo than other adenoviruses. Conclusion: Taken together, the combination of upregulation of TRAIL and downregulation of siXIAP with one oncolytic adenoviral vector holds promise for development of an effective therapy for melanomas and other common cancers.

• Asian Pacific Journal of Cancer Prevention
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• 제15권6호
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• pp.2453-2459
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• 2014

Ginsenoside Rg1 is one effective anticancer and antioxidant constituent of total saponins of Panax ginseng (TSPG), which has been shown to have various pharmacological effects. Our previous study demonstrated that Rg1 had anti-tumor activity in K562 leukemia cells. The aim of this study was designed to investigate whether Rg1 could induce apoptosis in TF-1/Epo cells and further to explore the underlying molecular mechanisms. Here we found that Rg1 could inhibit TF-1/Epo cell proliferation and induce cell apoptosis in vitro in a concentration and time dependent manner. It also suppressed the expression of EpoR on the surface membrane and inhibited JAK2/STAT5 pathway activity. Rg1 induced up-regulation of Bax, cleaved caspase-3 and C-PAPR protein and down-regulation of Bcl-2 and AG490, a JAK2 specific inhibitor, could enhance the effects of Rg1. Our studies showed that EpoR-mediated JAK2/STAT5 signaling played a key role in Rg1-induced apoptosis in TF-1/Epo cells. These results may provide new insights of Rg1 protective roles in the prevention a nd treatment of leukemia.

• Journal of Microbiology and Biotechnology
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• 제31권10호
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• pp.1343-1349
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• 2021

Cockroaches live in places where various pathogens exist and thus are more likely to use antimicrobial compounds to defend against pathogen intrusions. We previously performed an in silico analysis of the Periplaneta americana transcriptome and detected periplanetasin-5 using an in silico antimicrobial peptide prediction method. In this study, we investigated whether periplanetasin-5 has anticancer activity against the human leukemia cell line K562. Cell growth and survival of K562 cells treated with periplanetasin-5 were decreased in a dose-dependent manner. By using flow cytometric analysis, acridine orange/ethidium bromide (AO/EB) staining and DNA fragmentation, we found that periplanetasin-5 induced apoptotic and necrotic cell death in leukemia cells. In addition, these events were associated with increased levels of the pro-apoptotic proteins Fas and cytochrome c and reduced levels of the anti-apoptotic protein Bcl-2. Periplanetasin-5 induces the cleavage of pro-caspase-9, pro-caspase-8, pro-caspase-3, and poly (ADP-ribose) polymerase (PARP). The above data suggest that periplanetasin-5 induces apoptosis via both the intrinsic and extrinsic pathways. Moreover, caspase-related apoptosis was further confirmed by using the caspase inhibitor carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]-fluoromethylketone (Z-VAD-FMK), which reversed the periplanetasin-5-induced reduction in cell viability. In conclusion, periplanetasin-5 caused apoptosis in leukemia cells, suggesting its potential utility as an anticancer therapeutic agent.

• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1737-1740
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• 2011

• 생명과학회지
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• 제22권10호
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• pp.1277-1285
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• 2012

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)은 암세포 선택적으로 작용하므로서 유용한 항암제로 주목 받고 있다. 그러나, TRAIL 에 내성을 나타내는 암세포도 많이 존재한다. 그러므로 TRAIL 내성을 극복할 수 있는 방법을 고안하는 연구는 암 치료 요법에 매우 중요하다. 본 연구에서는 SIRT1 siRNA 또는 SIRT1 inhibitor인 amurensin G를 사람 유방암세포에 처리하면 DR5및 c-Myc의 발현 증강과 c-$FLIP_{L/S}$ 및 Mcl-1 발현 억제를 유도하므로서, TRAIL 에 내성을 나타내는 사람유방암세포 MCF-7 세포의 TRAIL 감수성을 증강시킴을 알 수 있었다. 또한, SIRT1 억제에 의한 caspase 활성화, PARP cleavage 및 Bcl-2 발현감소를 나타내었다. 이러한 연구결과는 SIRT1 저해에 의한 DR5 유도와 함께 c-FLIP 발현 억제가 TRAIL 내성 암세포의 TRAIL 반응성 증강에 유용한 기전으로 사용 될 수 있음을 시사하였다.

• BMB Reports
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• 제36권5호
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• pp.468-474
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• 2003

The molecular mechanism of hypoxia-induced apoptosis has not been clearly elucidated. In this study, we investigated the involvement of extracellular signal-regulated protein kinase (ERK 1/2) in hypoxia-induced apoptosis using cobalt chloride in HeLa human cervical cancer cells. The cobalt chloride was used for the induction of hypoxia, and its $IC_{50}$ was $471.4\;{\mu}M$. We demonstrated the DNA fragmentation after incubation with concentrations more than $50\;{\mu}M$ cobalt chloride for 24 h, and also evidenced the morphological changes of the cells undergoing apoptosis with electron microscopy. Next, we examined the signaling pathway of cobalt chloride-induced apoptosis in HeLa cells. ERK1/2 activation occurred 6 and 9 h after treatment with $600\;{\mu}M$ cobalt chloride. Meanwhile, the pretreatment of the MEK 1 inhibitor (PD98059) completely blocked the cobalt chloride-induced ERK 1/2 activation. At the same time, the activated ERK 1/2 translocated into the nucleus and phosphorylated its transcriptional factor, c-Jun. In addition, the pretreatment of PD98059 inhibited the cobalt chloride-induced DNA fragmentation and apoptotic cell death. These results suggest that cobalt chloride is able to induce apoptotic activity in HeLa cells, and its apoptotic mechanism may be associated with signal transduction via ERK 1/2.

• Asian Pacific Journal of Cancer Prevention
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• 제15권18호
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• pp.7919-7923
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• 2014

20(S)-Protopanaxadiol (PPD), a ginsenoside isolated from Pananx quinquefolium L., has been shown to inhibit growth and proliferation in several cancer cell lines. The aim of this study was to evaluate its anticancer activity in human breast cancer cells. MCF-7 cells were incubated with different concentrations of 20(S)-PPD and cytotoxicity was evaluated by MTT assay. Occurrence of apoptosis was detected by DAPI and Annexin V-FITC/PI double staining. Mitochondrial membrane potential was measured with Rhodamine 123. The Bcl-2 and Bax expression were determined by Western blot analysis. Caspase activity was measured by colorimetric assay. 20(S)-PPD dose-dependently inhibited cell proliferation in MCF-7 cells, with an $IC_{50}$ value of $33.3{\mu}M$ at 24h. MCF-7 cells treated with 20(S)-PPD presented typical apoptosis, as observed by morphological analysis in cell stained with DAPI. The percentages of annexin V-FITC positive cells were 8.92%, 17.8%, 24.5% and 30.5% in MCF-7 cells treated with 0, 15, 30 and $60{\mu}M$ of 20(S)-PPD, respectively. Moreover, 20(S)-PPD could induce mitochondrial membrane potential loss, up-regulate Bax expression and down-regulate Bcl-2 expression. These events paralleled activation of caspase-9, -3 and PARP cleavage. Apoptosis induced by 20(S)-PPD was blocked by z-VAD-fmk, a pan-caspase inhibitor, suggesting induction of caspase-mediated apoptotic cell death. In conclusion, the 20(S)-PPD investigated is able to inhibit cell proliferation and to induce cancer cell death by a caspase-mediated apoptosis pathway.

• Journal of Korean Neurosurgical Society
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• 제40권1호
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• pp.1-5
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• 2006

Objective : Survivin is an inhibitor of apoptosis protein[IAP], which inhibits apoptosis through a pathway distinct from the Bcl-2 family members. Overexpression of survivin and Bcl-2 have been commonly reported in human neoplasms. The authors investigate whether there is a synergistic effect on the anti-apoptosis rate of primary brain tumors "in situ" based on the co-expression of survivin and Bcl-2. Methods : One hundred and two brain tumor patients who had been resected were included in this study. Survivin tin and Bcl-2 were detected by Western blotting analysis, while apoptosis was examined by DNA fragmentation analysis. An anti-apoptotic rate was assessed in these brain tumor samples based on the expression of survivin and Bcl-2 or co-expression of both. Results : Survivin and Bcl-2 were expressed in 57[55.9%] and 53[52.0%] of 102 brain tumor samples studied respectively, and co-expressed in 31[30.4%]. The percentage of astrocytic and meningeal tumors expressing survivin was significantly correlated with histological grades; however, Bcl-2 was not correlated [p=0.106]. The anti-apoptotic rate in primary brain tumors with survivin, Bcl-2, and both was detected in 49[86.0%] of 57 samples, 42[79.9%] of 53 samples, and 27[87.1%] of 31 samples, respectively. Their difference in the frequency of anti-apoptosis was not significant. Conclusion : Survivin or Bcl-2 is involved in the anti-apoptosis. However, it suggests that co-expression of survivin and Bcl-2, together, have no synergistic effect on the anti-apoptotic properties of the primary brain tumors.

• 대한한의학회지
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• 제27권1호
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• pp.220-228
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• 2006

Objectives : Interleukin-1 (IL-1)${\beta}$ in articular chondrocytes regulates differentiation, apoptosis, and inflammatory responses. It is still controversial, So, we investigated IL- $1{\beta}$ induces chondrocytes dedifferentiation and death. Also, we studied the role of the mitogen-activated protein kinase (MAPK) subtypes on IL-$1{\beta}$-induced dedifferentiation and apoptosis. Methods : To evaluation of dedifferentiation by chemokines of chondrocytes, we assessed such as proteoglycan, collagen, MMP-3 and MMP-13 by RT-PCR analysis. Also, to assess of apoptosis effect by chemokines, we measured annexin V/propidium iodode (PI) and sub G1 cells in chondrocytes by flowcytometric analysis Results : IL-$1{\beta}$ treatment did not affect activation of ERK-1/2, but stimulation of p38 kinase. Inhibition of phospho ERK-1/2 with PD98059 enhanced IL-1b-induced dedifferentiation, and apoptosis up to 13.5%, whereas inhibition of phospho p38 kinase with SB203580 inhibited dedifferentiation, and apoptosis. Conclusions : Our results indicate that SB203580, p38 kinase inhibitor, inhibits IL-$1{\beta}$-induced dedifferentiation, and apoptosis by the inhibition of type II collagen expression and proteoglycan synthesis of rabbit articular chondrocytes.