• Molecules and Cells
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• 제24권3호
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• pp.378-387
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• 2007

The Bcl-2 family of proteins interacts at the mitochondria to regulate apoptosis. However, the anti-apoptotic Bcl-2 and $Bcl-X_L$ are not completely localized to the mitochondria. In an attempt to generate Bcl-2 and $Bcl-X_L$ chimeras that are constitutively localized to the mitochondria, we substituted their C-terminal transmembrane tail or both the C-terminal transmembrane tail and the adjacent loop with the equivalent regions from Bak or Bax mutant (BaxS184V) as these regions determine the mitochondrial localization of Bak and Bax. The effects of these substitutions on subcellular localization and their activities were assessed following expression in HeLa and CHO K1 cells. The substitution of the C-terminal tail or the C-terminal tail and the adjacent loop of Bcl-2 with the equivalent regions from Bak or the Bax mutant resulted in its association with the mitochondria. This change in subcellular localization of Bcl-2 chimeras triggered cells to undergo apoptotic-like cell death. The localization of this Bcl-2 chimera to the mitochondria may be associated with the disruption of mitochondrial membrane potential. Unlike Bcl-2, the loop structure adjacent to the C-terminal tail in $Bcl-X_L$ is crucial for its localization. To localize the $Bcl-X_L$ chimeras to the mitochondria, the loop structure next to the C-terminal tail in $Bcl-X_L$ protein must remain intact and cannot be substituted by the loop from Bax or Bak. The chimeric $Bcl-X_L$ with both its C-terminal tail and the loop structure replaced by the equivalent regions of Bak or Bax mutant localized throughout the entire cytosol. The $Bcl-X_L$ chimeras that are targeted to the mitochondria and the wild type $Bcl-X_L$ provided same protection against cell death under several death inducing conditions.

• 대한골관절종양학회지
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• 제11권2호
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• pp.118-125
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• 2005

목적: 골육종에서 세포 사멸과 관련된 survivin, bcl-2, bax 유전자의 발현을 조사하여 임상적 결과와의 연관성에 대해 알아 보고자 하였다. 대상 및 방법: 항암 약물 치료 전 절개 생검으로 얻은 50예의 골육종 조직을 면역조직화학 염색법을 통하여 survivin, bcl-2, bax의 발현을 관찰하였다. 임상적으로 항암 약물 치료에 대한 반응율, 국소재발, 원격전이, 종양학적 결과 등을 연구하여 surviving, bcl-2, bax 유전자 각각의 발현 또는 이들의 복합적인 발현과의 연관성에 대해 통계적으로 분석하였다. 결과: 면역조직화학염색법으로 검사한 survivin 유전자의 발현은 26예(52%)에서 관찰되었고, bcl-2는 23예 (46%), bax는 21예 (42%)에서 관찰되었다. Survivin과 bcl-2의 공동발현은 19예(38%), survivin과 bax의 공동 발현은 13예(26%), bcl-2와 bax의 공동 발현은 8예 (16%), 그리고 이들 3가지 모두의 발현은 총 8예 (16%)에서 관찰되었다. 검사한 3가지 세포 사멸 관련 유전자의 발현과 여러 임상적 변수와의 상관 관계를 조사 하였을 때 조직학적 분류, 나이, 성별, 국소 재발 등과는 유의한 연관성이 없었다. 항암 약물 반응율과 통계적으로 유의한 연관성을 보인 인자는 bcl-2 (P=0.04), 그리고 survivin과 bcl-2가 동시 발현된 경우 (P=0.044)였으며 나쁜 항암 약물 반응율을 나타냈다. 종양학적 결과 중 질병으로 인한 사망과의 연관성을 보인 인자 역시 bcl-2 (P=0.001), 그리고 survivin과 bcl-2가 동시발현된 경우 (P=0.027)였으며, 이들의 발현은 나쁜 종양학적 결과를 나타냈다. Kaplan-Meier 생존율 분석에서 bcl-2 (P=0.0012)의 발현과 survivin, bcl-2의 동시 발현 (P=0.0075)은 생존율과 역의 상관관계를 보였다. 결론: 골육종에서 세포 사멸 관련 유전자의 발현은 비교적 높게 보였으며, bcl-2의 발현은 항암 약물치료에 대한 불량한 반응과 낮은 생존율에 의미 있는 연관성을 보이며, survivin은 bcl-2와 동시에 발현되는 경우에만 이러한 종양학적 결과와 의미 있는 관련이 있었다. 따라서 세포 사멸 관련 유전자들의 면역조직화학염색법을 통한 관찰이 골육종의 예후 판정에 도움이 될 것으로 사료된다.

• Radiation Oncology Journal
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• 제27권4호
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• pp.218-227
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• 2009

목 적: 전립샘암 세포주 DU 145에서 엑스선과 중성자선에 의한 HIF-$1\alpha$와 아포프토시스 발현의 차이를 비교함으로써 엑스선과 중성자선의 방사선생물학적 차이의 기전을 알아보고자 한다. 대상 및 방법: 누드 마우스에 DU 145 전립샘암 세포주를 주입한 후 2 Gy 엑스선, 10 Gy 엑스선, 0.6 Gy 중성자선, 3.3 Gy 중성자선을 각각 조사했다. 엑스선을 조사한 군과 중성자선을 조사한 군에서 HIF-$1\alpha$, Bcl-2, Bax, 아포프토시스 발현 정도를 면역조직화학 염색과 western blotting을 이용하여 비교하였다. 아포토시스의 정도는 terminal deoxynucleotidyl biotin-dUTP nick end labeling (TUNEL) 염색을 이용하여 비교하였다. 결 과: 방사선 조사 1일째, X선을 조사한 군과 비교했을 때, 중성자선을 조사한 군에서 HIF-$1\alpha$와 Bcl-2의 발현은 감소하였고, Bax와 아포프토시스 세포의 수는 증가하였다. Bcl-2/Bax 비는 중성자선을 조사한 군에서 의미 있게 감소하였다. 이러한 HIF-$1\alpha$, Bcl-2, Bax, Bcl-2/Bax 비, 아포프토시스 발현의 차이는 방사선 조사 5일째에도 동일하게 유지되어 나타났다. 또한, HIF-$1\alpha$ 발현은 방사선 조사 5일째 Bcl-2 (p=0.031), Bax (p=0.037), TUNEL (p=0.016) 발현과 연관성을 보였다. 결 론: 중성자선 조사한 경우 엑스선에 비해 HIF-$1\alpha$와 Bcl-2 발현, Bcl-2/Bax 비가 감소하고, Bax 발현은 증가하였다. 중성자선 치료의 광자선과 다른 방사선생물학적인 반응은 HIF-$1\alpha$와 그로 인한 아포프토시스 관련 단백질 발현의 차이와 연관성이 있을 것으로 생각한다.

• Journal of Microbiology and Biotechnology
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• 제18권9호
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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.

• 한국식품영양과학회지
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• 제35권6호
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• pp.671-676
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• 2006

본 연구는 생강의 대표적인 비휘발성 매운맛 성분인 [6]-gingerol이 인체 유방암세포 MDA-MB-231에서 세포사멸에 미치는 영향을 살펴보았으며 그 결과는 다음과 같다. 세포사멸을 억제하는 단백질인 Bcl-2의 발현은 [6]-gingerol의 농도가 증가할수록 발현이 감소되었으며, mRNA 수준에서도 같은 양상을 보였다. 세포사멸을 유도하는 Bax의 단백질 발현은 [6]-gingerol의 농도가 증가되어도 유의적인 차이는 나타나지 않았으며 mRNA 수준에도 별 영향을 미치지 않았다. 그러나 세포사멸의 지표로 사용되는 Bcl-2/Bax의 비율은 [6]-gingerol의 농도가 증가할수록 감소를 보였다. 그리고 [6]-gingerol의 농도가 증가할수록 caspase-3의 활성이 증가하였다. 이상의 결과들로 볼 때, 인체 유방암 세포인 MDA-MB-231에서 [6]-gingerol은 암세포의 증식을 억제하고, 세포사멸을 유도하는 효과가 있는 것으로 사료된다.

• Archives of Pharmacal Research
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• 제22권5호
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• pp.448-453
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• 1999

In ginsenoside Rh2-treated rat glioma C6Bu-1 cells, apoptotic morphological changes, such as cell shrinkage, chromatin condensation and pyknosis were confirmed by means of electron microscopy. To evaluate whether induction of apoptosis by ginsenoside Rh2 is mediated by the members of Bcl-2 family, we first established C6Bu-1 cells overexpressing Bcl-2. It was demonstrated that the expression of Bcl-2, Bcl-xL, and Bax was not altered in ginsenoside Rh2-treated C6Bu-1 overexpressing C6Bu-1 cells failed to prevent from ginsenoside Rh2-induced cell death. These results suggest the existence of other apoptotic pathway that requires induction of apoptosis by ginsenoside Rh2 rather than the pathway through Bcl-2, $Bcl-x_{L}$ or Bax in C6Bu-1 cells.

• Clinical and Experimental Reproductive Medicine
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• 제29권3호
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• pp.167-178
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• 2002

Objective : The present study was performed to investigate whether apoptosis occur in human embryos by annexin staining and detect the expression of Fas, Fas-ligand (FasL), Bax, and Bcl-2 in human fragmented embryos derived from IVF-ET by immunofluorescence and Western blot analysis. Materials and Methods: Using annexin staining, immunofluorescence and Western blot analysis on normal and fragmented embryos, we were able to detect apoptotsis and apoptotic gene products in fragmented embryos. Result: Phosphatidylserine (PS) translocation, the marker for apoptosis, were detected frequently in fragmented embryos. Bcl-2 and Bax protein were detected in both fragmented and non-fragmented embryos. When fragmented embryos compared to normal embryos, immunofluorescent intensity of Bcl-2 tended to be lower in fragmented embryos. Bax gene expression increased in the fragmented embryos compared to the normal embryos. This result supports a model in which the molar ratio of Bcl-2 to Bax determines whether apoptosis induced or inhibited in human embryo. Fas was highly expressed in human preimplantation embryos but not FasL. It suggests that embryo may undergo apoptosis by binding with FasL produced by follicular or immune cells. Conclusion: The over expression of Bax and Fas will trigger apoptosis to lead embryo fragmentation and change embryo to be nonviable.

• 대한두경부종양학회지
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• 제16권2호
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• pp.161-166
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• 2000

Objective: The nm23 gene has been identified as a potential metastasis suppressor gene in various human neoplasms. Both Bcl-2, which promotes cell survival, and Bax, which promotes cell death, have been considered as major factors in controlling the apoptotic pathway. This study was carried out to determine whether these markers are useful in distinguishing potential intrinsic differences in tumor virulence of papillary thyroid cancers. Material and Method: The expressions of nm23, Bcl-2 and Bax have been evaluated using immunohistochemical techniques in 100 pure papillary thyroid cancers and 20 metastatic lymphnodes. The intensity of immnunoreactivity was graded on arbitrary four point scale(grade 0 or 1 : negative reactivity, grade 2 or 3 positive reactivity). The immunoreactivities were analyzed in relation to TNM atage, AMES score, local recurrence and distant metastasis, and that of metastatic LNs was compared with the tumors. Results: The expression of Bcl-2 and bax did not show any statistical differences by TNM stage, AMES score, recurrence, distant metastasis and also between the tumor and metastatic LN. However, the nm23 showed higher expression of Ki67 in distant metastasis than in control group and in metastatic LNs than in the tumors(p<0.05). Conclusion: Although the expression of Bcl-2 and Bax protein showed no correlation with clinical parameters representing tumor virulence, the nm23 expression could be an useful prognostic factor, especially in predicting nodal or distant metastasis in papillary thyroid cancer.

• Clinical and Experimental Reproductive Medicine
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• 제47권3호
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• pp.155-160
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• 2020

Objective: The genes Bcl-2 and Bax play important roles in apoptosis. Many studies have shown that formalin has a strong deleterious effect on male fertility and can induce apoptosis. L-carnitine has been reported to potentially reverse the negative effects of formalin, leading to improved spermatogenesis. In this study, we examined the levels of expression of Bcl-2 and Bax in mice treated with formalin and L-carnitine. Methods: Thirty adult BALB/c mice were categorized into three groups. The mice in the control group (n = 10) were not injected with any substance. The mice in the second group (n = 10) received 10 mg/kg of formalin daily via an intraperitoneal injection, while those in the final group (n = 10) were intraperitoneally injected daily with a dose of 10 mg/kg of formalin and 100 mg/kg of L-carnitine. All mice were kept in isolated cages for 31 days. Results: The expression of Bax was significantly higher in the formalin-treated mice than in the mice of the control group, while the expression of Bcl-2 was significantly lower in the formalin-treated mice than in the control mice. Additionally, relative to control mice, Bcl-2 expression increased and Bax expression decreased in the mice administered both formalin and L-carnitine. Conclusion: In this study, L-carnitine was shown to augment Bcl-2 expression and to reduce Bax expression, indicating that this compound may inhibit apoptosis. Due to its positive effects, L-carnitine can be used as a prophylactic treatment for people who routinely come into direct contact with formalin as an occupational hazard.

• 한방재활의학과학회지
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• 제18권2호
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• pp.33-43
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• 2008

Objectives : Sunghyangjungki-san(Xingxiangzhengqi-san) is a herb decoction prescribed frequently for stroke patients. The present study investigated neuroprotective effects of Sunghyangjungki-san(Xingxiangzhengqi-san) against the ischemic damage of the rat brain. Neuronal cell death under the cerebral ischemia is distinguished with the delayed cell death through apoptosis. Consequently, the effects of Sunghyangjungki-san(Xingxiangzhengqi-san) was evaluated with Bax and Bcl-2 expressions as apoptosis related factors in the brain tissues. Methods : The ischemic damage was induced by the middle cerebral artery occlusion(MCAO) method in Sprague-Dawley rats. Water extract of Sunghyangjungki-san(Xingxiangzhengqi-san) was treated for 5 days after the MCAO. Neurological scores and infarct size with TTC were measured. Bax and Bcl-2 expressions in the brain tissues were observed with immunohistochemistry. Results : Sunghyangjungki-san(Xingxiangzhengqi-san) treatment improved neurological score significantly at 5 days after the MCAO. Sunghyangjungki-san(Xingxiangzhengqi-san) treatment decreased infarct size by the MCAO, but it was not significant statistically. Sunghyangjungki-san(Xingxiangzhengqi-san) treatment attenuated Bax positive neurons significantly in the cerebral penumbra and the caudate putamen. Bcl-2 positive neurons were increased, but not significant. Sunghyangjungki-san(Xingxiangzhengqi-san) treatment increased Bcl-2/Bax expression ratios significantly in the cerebral penumbra and the caudate putamen. Conclusions : These results suggest that Sunghyangjungki-san(Xingxiangzhengqi-san) has a neuroprotective effect on the stroke with modulation of apoptosis related factors.