• BMB Reports
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• 제36권3호
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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.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.2425-2427
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• 2012

Ornithine decarboxylase (ODC), the first enzyme in the polyamine biosynthesis, plays an important role in tumor progression, cell proliferation and differentiation. In recent years, ODC has been the subject of intense study among researchers, as a target for anti-cancer therapy and specific inhibitory agents, have the potential to suppress carcinogenesis and find applications in clinical therapy. In particular, it is suggested that ODC is a promising candidate target for natural products in cancer chemoprevention. Future exploration of ornithine decarboxyalse inhitors present in nature may offer great hope for finding new cancer chemporeventive agents.

• Biomolecules & Therapeutics
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• 제20권1호
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• pp.19-26
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• 2012

There are many cyclic peptides with diverse biological activities, such as antibacterial activity, immunosuppressive activity, and anti-tumor activity, and so on. Encouraged by natural cyclic peptides with biological activity, efforts have been made to develop cyclic peptides with both genetic and synthetic methods. The genetic methods include phage display, intein-based cyclic peptides, and mRNA display. The synthetic methods involve individual synthesis, parallel synthesis, as well as split-and-pool synthesis. Recent development of cyclic peptide library based on split-and-pool synthesis allows on-bead screening, in-solution screening, and microarray screening of cyclic peptides for biological activity. Cyclic peptides will be useful as receptor agonist/antagonist, RNA binding molecule, enzyme inhibitor and so on, and more cyclic peptides will emerge as therapeutic agents and biochemical tools.

• 약학회지
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• 제15권1호
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• pp.16-23
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• 1971

Seven organic arsine compounds are synthesized as potential anti-tumor agents are subjected to the screening test of activity against SN-36 Leukemia, Sarcoma 180 and Ehrlich ascites carcinoma. Three compounds, namely N-(5-Nitrofroyl)-p-arsanilic acid, N-(2, 4-Dihydroxybenzoethyl)-p-arsanilic acid and N-$\alpha$(p-arsanilido) acetyl thiourea of the all synthesized compounds showed comparatively potential activities against experimental ascitic tumors both through cytological findings and survival duration.

• 동의생리병리학회지
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• 제19권2호
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• pp.441-445
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• 2005

Tripterygium regelii has been used as an oriental medicine, especially antiparasitic, anti-inflammatory and detoxifying agents in East asia. During our research to develop new antitumor agents from natural products, MeOH ext. and CH2Cl2 ext. of Tripterygium regelii showed the potent antitumor activity. In order to purify active compounds from Tripterygium regelii, activity-guided fractionation was carried out. Silica gel and RP-18 column chromatography for the active fraction led to the isolation of two compounds and their antitumor activities were studied. Those two compounds didn't show potent antitumor activity against human tumor cell lines. The structure of two compounds were determined by $^1H-NMR$, $^{13}C-NMR$, DEPT, $^1H-^{13}C$ COSY and IR spectrum. Compound I and Compound II were turned out to be Celastrol, and ${\beta}-sitosteryl-3-o-{\beta}-D-glucopyranoside$ respectively.

• Journal of Pharmaceutical Investigation
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• 제34권1호
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• pp.23-27
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• 2004

The urushiol-ethanol corpuscle of 320 nM in average particle size was prepared and concentrated by ultra homogenization and centrifugation. The cytotoxic profiles of this particle for use as anti-tumor agent have been evaluated in vitro in cultures of human fibroblasts (MRC-9) and celvical carcinoma cells (CUMC-3). The cytotoxicty assays revealed that the inhibitor effect of $10^{-5}$ M urushiol-ethanol particle on the growth of MRC-9 was hardly detected, while CUMC-3 cells exhibited over 50% of growth inhibition under the same conditions. In addition, a clear multiple-unit ladder pater of apoptotic DNA was observed for the urushiol treated CUMC-3 cells. Thus, the results indicated that urushiol inhibited growth of celvical carcinoma cells by inducing apoptosis, which is a mechanism observed with other typical antitumor agents.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2003년도 춘계학술대회 논문집
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• pp.95.1-95
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• 2003

Ginger (Zingiber officinale Roscoe, Zingiberaceae) has a wide array of pharmacologic effects. Our previous studies have demonstrated that [6]-gingerol, a major pungent ingredient of ginger, inhibits mouse skin tumor promotion and anchorage-independent growth of cultured mouse epidermal cells stimulated with epidermal growth factor. In this study, we have investigated the molecular mechanisms underlying chemopreventive effects of [6]-gingerol on mouse skin carcinogenesis. Cyclooxygenase-2 (COX-2), a key enzyme in the formation of prostaglandins, has been recognized as a molecular target of many chemopreventive as well as anti-inflammatory agents. The murine COX-2 promoter contains several transcriptional elements, particularly those involved in regulating inflammatory processes. One of the essential transcription factors responsible for COX-2 induction is NF-kappa B. Topical application of [6]-gingerol inhibited the COX-2 expression through suppression of NF-kappa B activation in phorbol ester-treated mouse skin. [6]-Gingerol, through down-regulation of p38 MAPK, abrogated the DNA binding activity of NF-kappa B by blocking phosphorylation of p65/RelA at the Ser 536 residue. These findings suggest that [6]-gingerol exerts an anti-tumor promotional activity through inhibition of the p38 MAPK-NF-kappa B siganling cascade in mouse skin.

• Genomics & Informatics
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• 제6권1호
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• pp.44-49
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• 2008

Protein kinase C (PKC) is a family of kinases involved in the transduction of cellular signals that promote lipid hydrolysis. PKC plays a pivotal role in mediating cellular responses to extracellular stimuli involved in proliferation, differentiation and apoptosis. Comparative analysis of the PKC-${\alpha},{\beta},{\varepsilon}$ isozymes of 200 recently sequenced microbial genomes was carried out using variety of bioinformatics tools. Diversity and evolution of PKC was determined by sequence alignment. The ser/thr protein kinases of Streptomyces coelicolor A3 (2), is the only bacteria to show sequence alignment score greater than 30% with all the three PKC isotypes in the sequence alignment. S.coelicolor is the subject of our interest because it is notable for the production of pharmaceutically useful compounds including anti-tumor agents, immunosupressants and over two-thirds of all natural antibiotics currently available. The comparative analysis of three human isotypes of PKC and Serine/threonine protein kinase of S.coelicolor was carried out and possible mechanism of action of PKC was derived. Our analysis indicates that Serine/ threonine protein kinase from S. coelicolor can be a good candidate for potent anti-tumor agent. The presence of three representative isotypes of the PKC super family in this organism helps us to understand the mechanism of PKC from evolutionary perspective.

• Journal of Gastric Cancer
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• 제24권1호
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• pp.29-56
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• 2024

In recent years, remarkable progress has been made in the molecular profiling of gastric cancer. This progress has led to the development of various molecular classifications to uncover subtype-specific dependencies that can be targeted for therapeutic interventions. Human epidermal growth factor receptor 2 (HER2) is a crucial biomarker for advanced gastric cancer. The recent promising results of novel approaches, including combination therapies or newer potent agents such as antibody-drug conjugates, have once again brought attention to anti-HER2 targeted treatments. In HER2-negative diseases, the combination of cytotoxic chemotherapy and programmed cell death-1/programmed cell death ligand-1 (PD-1/PD-L1) inhibitors has become the established standard of care in first-line settings. In the context of gastric cancer, potential biomarkers such as PD-L1 expression, Epstein-Barr virus, microsatellite instability, and tumor mutational burden are being considered for immunotherapy. Recently, promising results have been reported in studies on anti-Claudin18.2 and fibroblast growth factor receptor 2 treatments. Currently, many ongoing trials are aimed at identifying potential targets using novel approaches. Further investigations will be conducted to enhance the progress of these therapies, addressing challenges such as primary and acquired resistance, tumor heterogeneity, and clonal evolution. We believe that these efforts will improve patient prognoses. Herein, we discuss the current evidence of potential targets for systemic treatment, clinical considerations, and future perspectives.

• Journal of Microbiology and Biotechnology
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• 제11권4호
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• pp.656-662
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• 2001

Angiogenesis is known as a crucial process in the growth and spreading of tumor cells. Accordingly, the effective inhibition of this process would appear to be a promising way to cure angiogenesis-related diseases, including cancer. This study demonstrates that acalycixenolide E (AX-E) from the marine organism Acalycigorgia inermis exhibits a potent anti-angiogenic activity both in vitro and in vivo. AX-E inhibits the bFGF-induced proliferation of HUVECs in a dose dependent manner, along with the bFGF-induced migration, invasion, and tube formation of HUVECs. Moreover, AX-E potently inhibits the in vivo neovascularization of the chorioallantoic membranes (CAMs) of growing chick embryos. interestingly, AX-E suppresses the expression of metalloproteases 2 and 9, yet shows no effect on their activities. The novel chemical structure and potent anti-angiogenic activity of AX-E will be of great value in elucidating the molecular mechanism of angiogenesis as well as in the development of a novel anti-angiogenic drug.