• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2001년도 제2회 생물정보학 국제심포지엄
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• pp.139-149
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• 2001

Since 1990, the National Cancer Institute(NCI) has screened more than 60.000 compounds against a panel of 60 human cancer cell lines. The 50-percent growth-inhibitory concentration (GI$_{50}$) values encode unexpectedly rich, detailed information on mechanisms of drug action and drug resistance. Each compound's pattern is like a fingerprint, essentially unique among the many billions of distinguishable possibilities. These activity patterns are being used in conjunction with molecular structural features of the tested agents to explore the NCI's database of more than 460, 000 compounds, and they are providing insight into potential target molecules and modulators of activity in the 60 cell lines. For example, the information is being used to search for candidate anticancer drugs that are not dependent on intact p53 suppressor gene function for their activity. It remains to be seen how effective this information-intensive strategy will be at generating new clinically active agents.s.

• Asian Pacific Journal of Cancer Prevention
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• 제14권8호
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• pp.4501-4507
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• 2013

Caveolin-1 is a scaffold protein on the cell membrane. As the main component of caveolae, caveolin-1 is involved in many biological processes that include substance uptake and transmembrane signaling. Many of these processes and thus caveolin-1 contribute to cell transformation, tumorigenesis, and metastasis. Of particular interest are the dual rolesof tumor suppressor and oncogene that caveolin-1 appear to play in different malignancies, including pancreatic cancer. Therefore, analyzing caveolin-1 regulators and understanding their mechanisms of actionis key to identifying novel diagnostic and therapeutic tools for pancreatic cancer. This review details the mechanisms of action of caveolin-1 regulators and the potential significance for pancreatic cancer treatment.

• Molecules and Cells
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• 제20권2호
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• pp.196-200
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• 2005

The neurofibromatosis type2 (NF2) tumor suppressor gene product, merlin, is structurally related to the ezrin-radixin-moesin (ERM) family of proteins that anchor the actin cytoskeleton to specific membrane proteins and participate in cell signaling. However, the basis of the tumor suppressing activity of merlin is not well understood. Previously, we identified a role of merlin as an inhibitor of the Ras-ERK signaling pathway. Recent studies have suggested that phosphorylation of merlin, as of other ERM proteins, may regulate its function. To determine whether phosphorylation of merlin affects its suppression of Ras-ERK signaling, we generated plasmids expressing full-length merlin with substitutions of serine 518, a potential phosphorylation site. A substitution that mimics constitutive phosphorylation (S518D) abrogated the ability of merlin to suppress effects of the Ras-ERK signaling pathway such as Ras-induced SRE transactivation, Elk-mediated SRE transactivation, Ras-induced ERK phosphorylation and Ras-induced focus formation. On the other hand, an S518A mutant, which mimics nonphosphorylated merlin, acted like wild type merlin. These observations show that mimicking merlin phosphorylation impairs not only growth suppression by merlin but also its inhibitory action on the Ras-ERK signaling pathway.

• BMB Reports
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• 제50권5호
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• pp.269-274
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• 2017

The biological activities of macrophage migration inhibitory factor (MIF) might be mediated through a classical receptor-mediated or non-classical endocytic pathway. JAB1 (C-Jun activation domain-binding protein-1) promotes the degradation of the tumor suppressor, p53, and the cyclin-dependent kinase inhibitor, p27. When MIF and JAB1 are bound to each other in various intracellular sites, MIF inhibits the positive regulatory effects of JAB1 on the activity of AP-1. The intestinal parasite, Anisakis simplex, has an immunomodulatory effect. The molecular mechanism of action of As-MIF and human JAB1 are poorly understood. In this study, As-MIF and hJAB1 were expressed and purified with high solubility. The structure of As-MIF and hJAB1 interaction was modeled by homology modeling based on the structure of Ace-MIF. This study provides evidence indicating that the MIF domain of As-MIF interacts directly with the MPN domain of hJAB1, and four structure-based mutants of As-MIF and hJAB1 disrupt the As-MIF-hJAB1 interaction.

• Biomolecules & Therapeutics
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• 제27권2호
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• pp.210-215
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• 2019

Colorectal cancer is one of the leading causes of cancer related death due to a poor prognosis. In this study, we investigated the effect of Gomisin G on colon cancer growth and examined the underlying mechanism of action. We found that Gomisin G significantly suppressed the viability and colony formation of LoVo cells. Gomisin G reduced the phosphorylation level of AKT implying that Gomisin G suppressed the PI3K-AKT signaling pathway. Gomisin G also induced apoptosis shown by Annexin V staining and an increased level of cleaved poly-ADP ribose polymerase (PARP) and Caspase-3 proteins. Furthermore, Gomisin G remarkably triggered the accumulation of cells at the sub-G1 phase which represents apoptotic cells. In addition, the level of cyclin D1 and phosphorylated retinoblastoma tumor suppressor protein (Rb) was also reduced by the treatment with Gomisin G thus curtailing cell cycle progression. These findings show the suppressive effect of Gomisin G by inhibiting proliferation and inducing apoptosis in LoVo cells. Taken together, these results suggest Gomisin G could be developed as a potential therapeutic compound against colon cancer.

• Journal of Microbiology and Biotechnology
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• 제24권12호
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• pp.1654-1663
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• 2014

To examine the effect of tumor suppressor protein p53 on the antitumor activity of 2-methoxyestradiol (2-MeO-$E_2$), 2-MeO-$E_2$-induced cell cycle changes and apoptotic events were compared between the human colon carcinoma cell lines HCT116 ($p53^{+/+}$) and HCT116 ($p53^{-/-}$). When both cell types were exposed to 2-MeO-$E_2$, a reduction in the cell viability and an enhancement in the proportions of $G_2/M$ cells and apoptotic sub-$G_1$ cells commonly occurred dose-dependently. These 2-MeO-$E_2$-induced cellular changes, except for $G_2/M$ arrest, appeared to be more apparent in the presence of p53. Immunofluorescence microscopic analysis using anti-${\alpha}$-tubulin and anti-lamin B2 antibodies revealed that after 2-MeO-$E_2$ treatment, impaired mitotic spindle network and prometaphase arrest occurred similarly in both cell types. Following 2-MeO-$E_2$ treatment, only HCT116 ($p53^{+/+}$) cells exhibited an enhancement in the levels of p53, p-p53 (Ser-15), $p21^{WAF1/CIP1}$, and Bax; however, the Bak level remained relatively constant in both cell types, and the Bcl-2 level decreased only in HCT116 ($p53^{+/+}$) cells. Additionally, mitochondrial apoptotic events, including the activation of Bak and Bax, loss of ${\Delta}{\psi}m$, activation of caspase-9 and -3, and cleavage of lamin A/C, were more dominantly induced in the presence of p53. The Bak-specific and Bax-specific siRNA approaches confirmed the necessity of both Bak and Bax activations for the 2-MeO-$E_2$-induced apoptosis in HCT116 cells. These results show that among 2-MeO-$E_2$-induced apoptotic events, including prometaphase arrest, up-regulation of Bax level, down-regulation of Bcl-2 level, activation of both Bak and Bax, and mitochondria-dependent caspase activation, the modulation of Bax and Bcl-2 levels is the target of the pro-apoptotic action of p53.

• 생명과학회지
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• 제31권4호
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• pp.400-409
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• 2021

천연 benzophenanthridine alkaloid의 일종인 sanguinarine에 의한 인간 암세포에서의 세포사멸 유도는 암 치료를 위한 잠재적 치료 가능성으로 여겨져 왔으나 기본적인 항암 기전은 여전히 불분명하다. 종양 억제제 p53의 결실 또는 돌연변이는 결장암세포의 항암제 내성에 대한 주요 원인으로 작용하다. 따라서, 본 연구에서는 정상 p53을 가진 HCT116 (p53+/+) 및 p53이 결여된 HCT116 (p53-/-) 결장암세포를 대상으로 sanguinarine에 의해 유도되는 세포사멸에서 p53의 역할을 조사하였다. 본 연구의 결과에 의하면, sanguinarine은 HCT116 (p53-/-) 세포에 비하여 HCT116 (p53+/+) 세포의 생존력을 현저히 감소시켰다. 아울러 sanguinarine은 HCT116 (p53-/-) 세포보다 HCT116 (p53+/+) 세포에서 p53 및 cyclin-dependent kinase 억제제 p21^WAF1/CIP1의 발현을 증가시키면서 DNA 손상 및 세포사멸의 유도를 증가시켰다. Sanguinarine은 HCT116 (p53+/+) 세포에서 외인성 및 내인성 세포사멸의 개시에 관여하는 caspase-8 및 caspase-9의 활성을 증가시켰으며, 전형적인 효과기 caspase인 caspase-3을 활성화시켰다. 또한, sanguinarine은 HCT116 (p53+/+) 세포에서 Bax/Bcl-2의 발현 비율을 증가시키고 미토콘드리아 손상을 유발하였지만, HCT116 (p53-/-) 세포에서는 이러한 현상이 관찰되지 않았다. 결론적으로 본 연구의 결과는 sanguinarine은 HCT116 결장암세포에서 p53 의존적으로 외인성 및 내인성 세포사멸의 경로 활성을 통하여 세포사멸을 유도하였음을 의미한다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권2호
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• pp.703-712
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• 2016

Monoclonal antibodies with specific antigens have been widely used as targeted therapy for cancer. Hep88 mAb is a monoclonal antibody which shows specific binding with anti-cancer effects against the HepG2 cell line. However, its mechanisms of action are still not completely understood. We examined cell cycling and apoptosis by flow cytometry and mRNA expression of factors involved in apoptosis and paraptosis in Hep88 mAb-treated HepG2 cells by real-time PCR. The cell-cycle analysis demonstrated that growth-inhibitory activity was associated with G2/M cell cycle arrest. Hep88 mAb induced a significant increase in apoptotic cell populations in a dose- and time-dependent manner. The mRNA expression results also suggested that the process triggered by Hep88 mAb involved up-regulation of tumor suppressor p53, pro-apoptotic Bax, Cathepsin B, Caspase-3 and Caspase-9, with a decrease of anti-apoptotic Bcl-2 - thus confirming paraptosis and apoptosis programmed cell death. These findings represent new insights into the molecular mechanisms underlying the anti-cancer properties of Hep88 mAb in liver cancer cells.

• 대한한방내과학회지
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• 제36권1호
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• pp.13-21
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• 2015

Objectives : In Korea, Rhus verniciflua Stokes (RVS) has been used in traditional medicine for various diseases such as back pain, syndromes of the blood system in women, gastrointestinal disease, and cancer. However, the molecular mechanisms of its anti-cancer activity have not been clearly elucidated yet. Methods : This study investigated the possible mechanisms by which RVS extract (RVE) exerts its anti-proliferative action in cultured human breast carcinoma MCF-7 cells. Results : Treatment with RVE in MCF-7 cells resulted in inhibition of cell viability through G1 arrest of the cell cycle and induction of apoptosis in a time- and concentration-dependent manner, as determined by MTT assay and flow cytometry analysis. The induction of G1 arrest by RVE treatment was associated with the inhibition of cyclin D1, cyclin-dependent kinase (Cdk) 2, retinoblastoma protein (pRB), and mouse double minute 2 (MDM2) expression. Moreover, RVE treatment concentration dependently increased the levels of tumor suppressor p53, which was associated with the marked induction of Cdk inhibitors such as p21 (Waf1/Cip1) and p27 (Kip1). However, the inhibition of p53 function by the wild-type p53-specific inhibitor, pifithrin-α, abolished the above-mentioned effects of RVE, showing that p53 was responsible for the cytotoxicity of RVE Conclusions : These data indicate that a molecular pathway involving p53-dependent G1 cell cycle arrest plays a pivotal role in the cellular response to RVE, and demonstrate the potential applications of RVE as an anti-cancer drug for breast cancer treatment.

• 생명과학회지
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• 제19권6호
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• pp.705-710
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• 2009

Sodium butyrate (NaBt)는 장에서 탄수화물대사로부터 생겨나는 짧은 천연지방산 사슬로 다양한 인간 암세포들 에게서 강력한 항암효능을 나타냄이 보고된 바 있지만 자세한 기전은 아직 알려져 있지 않다. 이 논문에서 우리는 NaBt가 주요 세포부착분자이면서 종양억제인자의 일종인 E-cadherin의 발현을 세포-특이적으로 촉진하는 기전을 연구하였다. 또한 NaBt는 E-eadherin의 발현을 촉진하는 것으로 알려진 p21의 발현도 증가시켰지만, NaBt에 의하여 증가한 p21은 E-cadherin의 활성화와 관련이 없음이 밝혀졌다. 그 대신에 NaBt는 CCAAT-box를 통한 E-cadherin 유전자의 프로모터 활성을 증가시킴으로써 E-cadherin의 발현을 전사수준에서 촉진하는 것 같다. 이렇게 NaBt에 의하여 증가된 E-cadherin은 주로 세포간 접촉면에 위치하면서 Hep3B 세포를 더 분화된 형태로 유도하여 NaBt의 항암활성이 나타나는 것 같다.