• Journal of Life Science
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• v.26 no.3
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• pp.376-386
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• 2016

Apoptosis induction has been proposed as an efficient mechanism by which malignant tumor cells can be removed following chemotherapy. The intrinsic mitochondria-dependent apoptotic pathway is frequently implicated in chemotherapy-induced tumor cell apoptosis. Since DNA-damaging agent (DDA)-induced apoptosis is mainly regulated by the tumor suppressor protein p53, and since more than half of clinical cancers possess inactive p53 mutants, microtubule-damaging agents (MDAs), of which apoptotic effect is mainly exerted via p53-independent routes, can be promising choice for cancer chemotherapy. Recently, we found that the apoptotic signaling pathway induced by MDAs (nocodazole, 17α-estradiol, or 2-methoxyestradiol) commonly proceeded through mitotic spindle defect-mediated prometaphase arrest, prolonged Cdk1 activation, and subsequent phosphorylation of Bcl-2, Mcl-1, and Bim in human acute leukemia Jurkat T cells. These microtubule damage-mediated alterations could render the cellular context susceptible to the onset of mitochondria-dependent apoptosis by triggering Bak activation, Δψm loss, and resultant caspase cascade activation. In contrast, when the MDA-induced Bak activation was inhibited by overexpression of anti-apoptotic Bcl-2 family proteins (Bcl-2 or Bcl-xL), the cells in prometaphase arrest failed to induce apoptosis, and instead underwent mitotic slippage and endoreduplication cycle, leading to formation of populations with 8N and 16N DNA content. These data indicate that cellular apoptogenic mechanism is critical for preventing polyploid formation following MDA treatment. Since the formation of polyploid cells, which are genetically unstable, may cause acquisition of therapy resistance and disease relapse, there is a growing interest in developing new combination chemotherapies to prevent polyploidization in tumors after MDA treatment.

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.394-398
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• 2000

A methanol extract of the root of Peucedanum japonicum, used as a medicinal herb, showed an inhibitory effect on mammalian topoisomerase I activity. The methanol extract was suspended in ethyl acetate, and a topoisomerase I inhibitor in the organic soluble fraction was then isolated by silica gel and thin layer chromatography. The topoisomerase I inhibitory compound was indentified as falcarindiol based on the analysis of EI-MS, $^1$H and \ulcornerC NMR spectroscopy. This inhibitory showed cytotoxicity against human leukemia Jurkat T and HL60 cells with an IC\ulcorner value of 7 $\mu\textrm{g}$/ml. These results suggest the possibility of falcarindiol as a new anticancer agent which can be expected to have a synergistic effect on other anticancer drugs. In addition, the present data show that falcarindiol has antifungal, yet not antibacterial, activity.

• Proceedings of the Korean Society of Life Science Conference
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• 2006.09a
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• pp.118.1-118.1
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• 2006

• Proceedings of the Korean Society of Life Science Conference
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• 2006.09a
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• pp.117.1-117.1
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• 2006

• Korean Journal of Medicinal Crop Science
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• v.26 no.1
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• pp.42-54
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• 2018

Background: Allergic diseases like such as atopic dermatitis, asthma, and rhinitis have recently increased both domestically and globally. The present study was undertaken to select candidates with anti-allergic activity from plant resources. Methods and Results: Fifty-six plant extracts at $20{\mu}g/m{\ell}$ were screened against ${\beta}$-hexosaminidase production and interleukin (IL)-4 release in degranulated rat basophilic leukemia (RBL)-2H3 cells. The anti-allergy activity of three plant extracts selected from the preliminary screening experiment, Polygonatum sibiricum F. Delaroche (root), Pyrus pytifolia var. culta (Makino) Nakai (leaf), and Rehmannia glutinosa (Gaertn.) Libosch. ex Steud (root) were measured at concentrations of $2-250{\mu}g/m{\ell}$ in three cell lines as RBL-2H3, HaCaT and Jurkcat T cells. The assay showed the root extract of R. glutinosa to have an inhibitory activity of 4.2% - 28.6% on ${\beta}$-hexosaminidase production from IgE-sensitized RBL-2H3 cells. Each extract of P. sibiricum and R. glutinosa reduced IL-4 release in IgE-sensitized RBL-2H3 cells, respectively. The leaf extract of P. pyrifolia var. culta showed a significantly potent suppressive effect of 10.2% - 74.7% on the mRNA expression of tumor necrosis factor (TNF)-${\alpha}$ in HaCaT cells sensitized with TNF-a and INF-g, and showed inhibitory effect of -8.6% - 90.9% on the mRNA expression of IL-2 in Jurkat T cells sensitized with PMA and A23187. Conclusions: The results showed that the root of R. glutinosa and leaf of P. pyrifolia var. culta could be useful candidates as antiallergy materials.

• Journal of Life Science
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• v.33 no.1
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• pp.15-24
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• 2023

To examine the antitumor effect of proso millet grains, whether proso millet grains exert apoptotic activity against human cancer cells was investigated. When the cytotoxicity of 80% ethanol (EtOH) extract of proso millet grains was tested against various cancer cells using MTT assay, more potent cytotoxicity was observed against human breast cancer MDA-MB-231 cells than against other cancer cells. When the EtOH extract was evaporated to dryness, dissolved in water, and then further fractionated by sequential extraction using four organic solvents (n-hexane, methylene chloride, ethyl acetate, and n-butanol), the BuOH fraction exhibited the highest cytotoxicity against MDA-MB-231 cells. Along with the cytotoxicity, TUNEL-positive apoptotic nucleosomal DNA fragmentation and several apoptotic responses including BAK/BAX activation, mitochondria membrane potential (Δψm) loss, mitochondrial cytochrome c release into the cytosol, activation of caspase-8/-9/-3, and degradation of poly (ADP-ribose) polymerase (PARP) were detected. However, human normal mammary epithelial MCF-10A cells exhibited a significantly lesser extent of sensitivity compared to malignant MDA-MB-231 cells. Irrespective of Fas-associated death domain (FADD)-deficiency or caspase-8-deficiency, human T acute lymphoblastic leukemia Jurkat cells displayed similar sensitivities to the cytotoxicity of BuOH fraction, excluding an involvement of extrinsic apoptotic mechanism in the apoptosis induction. These results demonstrate that the cytotoxicity of BuOH fraction from proso millet grains against human breast cancer MDA-MB-231 cells is attributable to intrinsic apoptotic cell death resulting from BAK/BAX activation, and subsequent mediation of mitochondrial damage-dependent activation of caspase cascade.

• KSBB Journal
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• v.22 no.1
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• pp.22-29
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• 2007

The water-soluble materials extracted from fruit bodies and mycelium of H. erinaceum were prepared. In-vitro anticancer activities on cancer cells and In-vivo proliferation effect on mouse peritoneal exudate cell and spleen cell of samples were investigated. Also, nitric oxide (NO) generation of peritoneal exudate cell, IL-2 production capacity of spleen cells and phagocytic activity of peritoneal macrophages were examined. The water extracts of H. erinaceum suppressed the proliferation of cancer cell (HeLa, Raw264.7, Jurkat, KATO3, EL4, LyD9) with concentration-dependent. The water extract from fruit body showed better suppression effect than that from mycelium in most of cancer cells used. The anticancer effect of water extract of fruits body in the range of 0.01 and 10 mg/ml for Raw 264.7 and EL4 cell lines were the same as the Taxol with one thousandth equivalent of fruit body concentration. Water extracts of fruit body and liquid-cultured products of H. erinaceum induced nitric oxide (NO) generation of peritoneal exudate cell and increased NO generation by stimulus of lipopolysaccharide. Water extracts alone did not induce the proliferation and IL-2 production capacity of spleen cells. However, spleen's proliferation and IL-2 production were induced significantly by the addition of lipopolysaccharide and Con A (concanavalin A) or Con A alone, and the effectiveness of mycelium extract with water were more active than those from fruit body.