• Biomolecules & Therapeutics
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• 제32권3호
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• pp.267-280
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• 2024

Apoptosis, programmed cell death pathway, is a vital physiological mechanism that ensures cellular homeostasis and overall cellular well-being. In the context of cancer, where evasion of apoptosis is a hallmark, the overexpression of anti-apoptotic proteins like Bcl2, Bcl-xL and Mcl-1 has been documented. Consequently, these proteins have emerged as promising targets for therapeutic interventions. The BCL-2 protein family is central to apoptosis and plays a significant importance in determining cellular fate serving as a critical determinant in this biological process. This review offers a comprehensive exploration of the BCL-2 protein family, emphasizing its dual nature. Specifically, certain members of this family promote cell survival (known as anti-apoptotic proteins), while others are involved in facilitating cell death (referred to as pro-apoptotic and BH3-only proteins). The potential of directly targeting these proteins is examined, particularly due to their involvement in conferring resistance to traditional cancer therapies. The effectiveness of such targeting strategies is also discussed, considering the tumor's propensity for anti-apoptotic pathways. Furthermore, the review highlights emerging research on combination therapies, where BCL-2 inhibitors are used synergistically with other treatments to enhance therapeutic outcomes. By understanding and manipulating the BCL-2 family and its associated pathways, we open doors to innovative and more effective cancer treatments, offering hope for resistant and aggressive cases.

• Molecules and Cells
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• 제37권3호
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• pp.264-269
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• 2014

The molecular interaction between tumor suppressor p53 and the anti-apoptotic Bcl-2 family proteins plays an essential role in the transcription-independent apoptotic pathway of p53. In this study, we investigated the binding of p53 DNA-binding domain (p53DBD) with the anti-apoptotic Bcl-2 family proteins, Bcl-w, Mcl-1, and Bcl-2, using GST pull-down assay and NMR spectroscopy. The GST pull-down assays and NMR experiments demonstrated the direct binding of the p53DBD with Bcl-w, Mcl-1, and Bcl-2. Further, NMR chemical shift perturbation data showed that Bcl-w and Mcl-1 bind to the positively charged DNA-binding surface of p53DBD. Noticeably, the refined structural models of the complexes between p53DBD and Bcl-w, Mcl-1, and Bcl-2 showed that the binding mode of p53DBD is highly conserved among the anti-apoptotic Bcl-2 family proteins. Furthermore, the chemical shift perturbations on Bcl-w, Mcl-1, and Bcl-2 induced by p53DBD binding occurred not only at the p53DBD-binding acidic region but also at the BH3 peptide-binding pocket, which suggests an allosteric conformational change similar to that observed in Bcl-$X_L$. Taken altogether, our results revealed a structural basis for a conserved binding mechanism between p53DBD and the anti-apoptotic Bcl-2 family proteins, which shed light on to the molecular understanding of the transcription-independent apoptosis pathway of p53.

• 한국산학기술학회논문지
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• 제14권8호
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• pp.3843-3849
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• 2013

이배체 단위발생 돼지 난자를 체외 배양시 배반포 형성 단계에서 FBS (우태아 혈청), BSA (우혈청 알부민), EGF(상피세포 성장인자)를 배양액에 첨가하였을 때 이배체 단위발생 에서 총세포수, 세포사멸 및 세포사멸에 관여하는 유전자의 발현 효과를 조사하고자 본 연구를 수행하였다. 0.4% BSA를 배양액에 첨가 하였을 때 2 세포기 단계 단위발생의 발달은 배반포 까지는 강화 되었다 (p<0.01). FBS 처리 시는 배반포의 세포 수는 감소시켰으나 세포 사멸률은 증가하였다(p<0.01). 하지만 EGF가 존재할 때 BSA 처리는 총 세포수를 증가 시켰다. RT-PCR의 결과에 의하면 EGF는 0.4% BSA가 존재하는 배양액에서는 Bcl-xL mRNA 발현을 증가시키고 BSA와 EGF 가 단독으로 존재 할 때는 효과가 없었다. 하지만 FBS 처리시 Bcl-xL 유전자 발현은 감소하고 Bak 유전자의 발현은 증가시킨다. 이러한 결과 세포사멸에 관여하는 유전자의 발현은 배양액의 첨가물에 따라 유의적으로 영향을 받으며, 돼지 배아의 체외 배양시 세포사멸과 초기발달에 관여함을 시사한다.

• Journal of Microbiology and Biotechnology
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• 제26권2호
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• pp.287-294
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• 2016

The effect of kaempferol (3,5,7,4-tetrahydroxyflavone), a flavonoid compound that was identified in barnyard millet (Echinochloa crus-galli var. frumentacea) grains, on G₂-checkpoint and apoptotic pathways was investigated in human acute leukemia Jurkat T cell clones stably transfected with an empty vector (J/Neo) or a Bcl-xL expression vector (J/Bcl-xL). Exposure of J/Neo cells to kaempeferol caused cytotoxicity and activation of the ATM/ATR-Chk1/Chk2 pathway, activating the phosphorylation of p53 (Ser-15), inhibitory phosphorylation of Cdc25C (Ser-216), and inactivation of cyclin-dependent kinase 1 (Cdk1), with resultant G₂-arrest of the cell cycle. Under these conditions, apoptotic events, including upregulation of Bak and PUMA levels, Bak activation, mitochondrial membrane potential (Δψm) loss, activation of caspase-9, -8, and -3, anti-poly (ADP-ribose) polymerase (PARP) cleavage, and accumulation of apoptotic sub-G₁ cells, were induced without accompanying necrosis. However, these apoptotic events, except for upregulation of Bak and PUMA levels, were completely abrogated in J/Bcl-xL cells overexpressing Bcl-xL, suggesting that the G₂-arrest and the Bcl-xL-sensitive mitochondrial apoptotic events were induced, in parallel, as downstream events of the DNA-damage-mediated G₂-checkpoint activation. Together these results demonstrate that kaempferol-mediated antitumor activity toward Jurkat T cells was attributable to G₂-checkpoint activation, which caused not only G₂-arrest of the cell cycle but also activating phosphorylation of p53 (Ser-15) and subsequent induction of mitochondria-dependent apoptotic events, including Bak and PUMA upregulation, Bak activation, Δψm loss, and caspase cascade activation.

• Radiation Oncology Journal
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• 제21권3호
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• pp.222-226
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• 2003

목적: 변이를 보이는 lpr 마우스와 Fas ligand 변이를 보이는 gld 마우스를 이용하여 in vivo에서 Fas와 Fas ligand의 발현이 전리 방사선에 의해 유도되는 apoptosis에서 어떤 역할을 하는지 조사하고자 하였다. 대상 및 방법: Fas의 변이를 보이는 $C57BL/6J-Fas^{lpr}$ 마우스와 대조군인 C57BL/6J 마우스, Fas ligand 변이를 보이는 $C3H/HeJ-Fas^{gld}$ 마우스와 대조군인 C3H/HeJ 마우스를 대상으로 하였다. 마우스는 8주령 웅성으로서 전신 방사선 조사하여 일정 시간 후 비장을 적출하였다. 조직을 hematoxylin-eosin 염색하여 apoptosis 유도 수준을 비교 분석하였다. 또한 apoptosis 조절 물질인 p53, Bcl-2, Bax, Bcl-X_L,\;Bcl-X_S$에 대하여 Western Western blotting을 시행하고 발현수준을 densitometry로 분석하여 관련된 기전을 연구하였다. 결과: 2.5 Gydh k10 Gy 조사시에 $C57BL/6J-Fas^{lpr}$ 마우스와 $C3H/HeJ-Fas^{gld}$ 마우스에서 대조군 비하여 방사선에 의한 apoptosis가 유의하게 감소되는 것으로 나타났다(p<0.05). C57BL/6J 마우스와, C3H/HeJ 마우스에서 10 Gy 방사선 조사 후 Bax가 8시간 째에 각각 3배, 3.3배의 증가를 보였으나 $C57BL/6J-Fas^{lpr}$ 마우스와, $C3H/HeJ-Fas^{gld}$ 마우스에서는 뚜렷한 발현증가가 관찰되지 않았다. 결과: Fas의 변이가 있는 lpr 마우스와 Fas ligand의 변이가 있는 gld 마우스에서 방사선에 의한 apoptosis가 대조군 보다 현저하게 낮으며 이는 방사선에 의한 Bax의 유도가 미약한 것과 연관된 것으로 나타났다. 방사선에 의한 apoptosis 유도에 Fas의 역할이 매우 중요한 것으로 보인다.

• Journal of Gastric Cancer
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• 제3권2호
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• pp.75-79
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• 2003

Purpose: Evidence exists that dysregulation of apoptosis is involved in the pathogenesis of cancer development. The Bcl-$x_{L}$/Bcl-2-associated death promoter (BAD), a member of the Bcl-2 family, is a critical regulatory component of the intrinsic cell-death pathway that exerts its pro-apoptotic effect upon heterodimerization with anti-apoptotic proteins Bcl-2 and Bcl-$X_{L}$. Expression of the BAD protein has been reported in several cancer types, but not in stomach cancer. The aim of this study was to explore the expression status of the BAD protein in gastric carcinomas. Materials and Methods: In the current study, we analyzed the expression of the BAD protein in 60 advanced gastric adenocarcinomas by using immunohistochemistry and a tissue microarray approach. Results: Immunopositivity (defined as $\geq\30\%$) was observed for the BAD protein in 57 ($95\%$) of the 60 cancers. Normal gastric mucosal cells showed weaker expressions of the BAD protein than gastric carcinomas. Conclusion: Taken together, these results suggest that stomach cancer cells in vivo may need BAD protein expression for apoptosis. Also, the higher expression of the BAD protein in stomach cancer cells than in normal gastric mucosal cells suggests that apoptosis might be easily triggered in susceptible stomach cancer cells, thereby producing selective pressure to make more apoptosis-resistant cells during tumor development.

• 생명과학회지
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• 제17권11호
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• pp.1596-1600
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• 2007

본 연구에서 봉독의 apoptosis 유도에 의한 항암기전 효능을 A549 인체폐암세포를 대상으로 조사하였으며, apoptosis 유발에 관여할 것으로 예상되는 중요한 유전자들의 발현 및 활성에 미치는 봉독의 영향을 조사하였다. A549 세포의 생존율은 봉독의 처리 농도 증가에 따라 강력하게 억제되었으며, 이는 염색질 응축 현상을 동반한 apoptosis 유발에 의한 것임을 알 수 있었다. 봉독 처리에 의한 apoptosis 유발은 Bax 및 Bcl-xL의 발현 변화 없이 Bcl-2의 발현 감소에 따른 상대적인 Bax의 발현 증가와 IAP family에 속하는 인자들의 발현 감소 및 caspase의 활성화와 연관성이 있었다.

• 생명과학회지
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• 제27권12호
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• pp.1507-1514
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• 2017

김치는 한국에서 가장 인기 있는 발효식품이며, 여러 연구에서 암예방, 항비만, 항염증 등의 활성을 가지는 건강기능성 식품으로 보고되고 있다. 본 실험에서는 김치의 기능성을 높이기 위하여 항암기능성이 알려진 겨우살이 추출물을 첨가하여 개발한 암환자용 김치(kimchi B)의 암세포 증식억제능 및 그 기전에 대하여 검토하였다. 인체 폐암 A549세포를 이용하여 증식저해 효과와 apoptosis 유도 및 관련된 mRNA 유전자 발현에 미치는 영향을 관찰하였으며, 대조군으로는 표준화김치(kimchi A)를 사용하였다. A549 인체 폐암 세포를 이용한 성장 저해시험에서 MTT 방법과 hemocytometer를 이용하여 암세포 수를 개수한 결과, 김치를 첨가한 군에서 농도 의존적으로 증식억제 효과가 나타났으며, 특히 kimchi B를 첨가한 군에서 더 높은 증식억제 효과를 확인할 수 있었다. DAPI 염색을 통해 암세포 핵의 형태적 특징을 조사한 결과 kimchi B를 첨가한 군에서 DNA단편이 발견되어, A549 인체 폐암세포의 증식억제효과는 apoptosis에 의한 것으로 관찰되었다. Apoptosis의 기전을 알아보기 위하여 Bcl-2 family (Bax, Bcl-2, Bcl-xL) 발현과 p53, p21 발현을 측정한 결과, kimchi B를 첨가한 군에서 Bax 유전자는 증가하고 Bcl-2 유전자 발현이 감소하여, 이들 유전자 발현과 관련되어 apoptosis가 유도되었음을 확인할 수 있었으며, 이들 유전자들의 발현은 p21 발현 증가에 의한 것으로 보아 kimchi B를 처리한 A549인체 폐암세포는 p53 비의존적인 p21 발현증가에 의해 암세포 증식저해 효과를 나타낸 것으로 사료된다. 이 연구를 바탕으로 암환자들을 위한 기능성이 증진된 김치 개발에 활용이 가능할 것으로 기대된다.

• Toxicological Research
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• 제23권3호
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• pp.215-221
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• 2007

Although sanguinarine, a benzophenanthridine alkaloid, possesses anti-cancer properties against several cancer cell lines, the molecular mechanisms by which it inhibits cell growth and induces apoptosis have not been clearly understood. In order to further explore the critical events leading to apoptosis in sanguinarine-treated MCF-7 human breast carcinoma cells, the following effects of sanguinarine on components of the mitochondrial apoptotic pathway were examined: generation of reactive oxygen species (ROS), alteration of the mitochondrial membrane potential (MMP), and the expression changes of Bcl-2 family proteins. We show that sanguinarine-induced apoptosis is accompanied by the generation of intracellular ROS and disruption of MMP as well as an increase in pro-apoptotic Bax expression and a decrease of anti-apoptotic Bcl-2 and Bcl-xL expression. The quenching of ROS generation with N-acetyl-L-cysteine, the ROS scavenger, protected the sanguinarine-elicited ROS generation, mitochondrial dysfunction, modulation of Bcl-2 family proteins, and apoptosis. Based on these results, we propose that the cellular ROS generation plays a pivotal role in the initiation of sanguinarine-triggered apoptotic death.

• 동의생리병리학회지
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• 제20권2호
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• pp.358-364
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• 2006

To investigate the possible mechanism of Drynariae Rhizoma extracts as a candidate of anti-cancer drug, I examined the effects of Drynariae Rhizoma extracts on the apoptosis of U937 cell line. MTT assay, flow cytometric analysis, SDS-polyacrylamide gel electrophoresis, Western blot analysis, and RT-PCR were performed. Drynariae Rhizoma extracts treatment reduced the cell viablilty of U937 cells in a dose-dependent manner, which was associated with induction of apoptotic cell death. Drynariae Rhizoma extracts treatment also reduced the levels of Bcl-xL anti-apoptotic protein expression and increased the levels of caspase-3, p53, pro-apoptotic protein, in U937 cells. RT-PCR data revealed that the level of bcl-2, bcl-xL mRNA expressions decreased in a dose-dependent manner. These findings suggest that Drynariae Rhizoma extracts may have induction of apoptotic cell death via regulation of several growth regulatory gene products. The abbreviations used are: FBS, fetal bovine serum; PBS, phosphate buffered saline; PI, propidium iodide; OD, optical density; DiOC6, 3,3-dihexyloxa carbcyanine iodide; MTT, 3 [4-5-dimethylthiazol-2-yl] -2-diphenyltetrazolium bromide.