• Journal of Microbiology and Biotechnology
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• v.17 no.11
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• pp.1856-1861
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• 2007

Physiological cell conditions such as glucose deprivation and hypoxia play roles in the development of drug resistance in solid tumors. These tumor-specific conditions cause decreased expression of DNA topoisomerase $II{\alpha}$, rendering cells resistant to topo II target drugs such as etoposide. Thus, targeting tumor-specific conditions such as a low glucose environment may be a novel strategy in the development of anticancer drugs. On this basis, we established a novel screening program for anticancer agents with preferential cytotoxic activity in cancer cells under glucose-deprived conditions. We recently isolated an active compound, AA-98, from Streptomyces sp. AA030098 that can prevent stress-induced etoposide resistance in vitro. Furthermore, LC-MS and various NMR spectroscopic methods identified AA-98 as mithramycin, which belongs to the aureolic acid group of antitumor compounds. We found that mithramycin prevents the etoposide resistance that is induced by glucose deprivation. The etoposide-chemosensitive action of mithramycin was just dependent on strict low glucose conditions, and resulted in the selective cell death of etoposide-resistant HT-29 human colon cancer cells.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.2235-2240
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• 2012

c-Src is one member of non-receptor tyrosine kinase protein family that has over expression and activation in many human cancer cells. It has been shown that c-Src is implicated in various downstream signaling pathways associated with EGFR-dependent signaling such as MAPK and STAT5 pathways. Transactivation of EGFR by c-Src is more effective than EGFR ligands. To inhibit the c-Src expression, we used c-Src antisense oligonucleotide complexed with PAMAM Denderimes. The effect of c-Src antisense oligonucleotide on HT29 cell proliferation was determined by MTT assay. Then, the expression of c-Src, EGFR and the genes related to EGFR-depended signaling with P53 was applied by real time PCR. We used western blot analysis to elucidate the effect of antisense on the level of c-Src protein expression. The results showed, c-Src antisense complexed with PAMAM denderimers has an effective role in decrease of c-Src expression and EGFR-dependent downstream genes.

• The Korean Journal of Food And Nutrition
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• v.5 no.1
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• pp.13-22
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• 1992

This study was divised to observe the inhibitory effect of growth rate of human colon cancer cells by Eucommial leaf extract, in vitro. Three species of human colon cancer cells, HRT-18, HCT-48 and HT-29, were used for the experiment. Each extract of Eucommial leaf was prepared by extraction with water, 95% alcohol, acetone, chloroform and petroleum ether, and then the inhibitory effect of each extract on the growth rate of cells was compared with control group and each other. The experimental results obtained are summarized as follows; 1. Inhibitory effects on growth rate of human colon cancer fells were strongest in the petroleum ether extract and next in the chloroform extract. 2. Inhibitory effects on the growth rate of the cancer cells by extracts of water, 95% alcohol and acetone were weaker than that of petroleum ether and chloroform. 3. Inhibitory effect of each extract on the cancer cell growth was shown most strong activity in HT-29, and was in order of HRT 18 and HCT-48. In view of the results, it could be suggested that inhibitory effects of non-polar solvent's extracts against the cancer cell growth were more stronger than that of polar solvents and the effects were indicated difference according to the species of the cells.

• Natural Product Sciences
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• v.25 no.1
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• pp.11-15
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• 2019

Lauraceae is a family medicinal plant whose tubers possesses antimicrobial, and cytotoxic, such as antiparasitic and anti-inflammatory special effects and has been used for the medicine in the cure of hepatitis and rheumatism. The antimicrobial activities of bioactive compounds including one neolignan; kunstlerone (1) and two alkaloids include isocaryachine (2) and noratherosperminine (3) as well as crude hexane, methanol and dichloromethane extracts were evaluated. Additionally, the effect of compounds 1, 2 and 3 were evaluated on A549, PC-3, A375, HT-29 and WRL-68 cell lines. In conclusion, kunstlerone 1 showed moderate cytotoxicity against various cancer cell lines such as A549, PC-3, A375, HT-29 and WRL-68, respectively with $EC_{50}$ values of 28.02, 26.78, 33.78, 33.65 and $16.46{\mu}g/mL$. The crude methanol extract showed antigrowth activity against S. pyogenes II and B. cereus, with MICs of $256{\mu}g/mL$. The compounds kunstlerone (1), isocaryachine (2) and noratherosperminine (3) showed complete inhibition against P. shigelloides, with MIC ${\leq}60{\mu}g/mL$ compare to ampicillin, as a positive control, which showed antigrowth activity against P. shigelloides at MIC $10{\mu}g/mL$.

• Food Science of Animal Resources
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• v.41 no.2
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• pp.261-273
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• 2021

Leuconostoc mesenteroides H40 (H40) was isolated from kimchi, and its probiotic properties and neuroprotective effect was evaluated in oxidatively stressed SH-SY5Y cells. H40 was stable in artificial gastric conditions and can be attached in HT-29 cells. In addition, H40 did not produce β-glucuronidase and showed resistant to several antibiotics. The conditioned medium (CM) was made using HT-29 cells refined with heat-killed probiotics (Probiotics-CM) and heated yogurts (Y-CM) to investigate the neuroprotective effect. Treatment with H40-CM not only increased cell viability but also significantly improved brain derived neurotropic factor (BDNF) expression and reduced the Bax/Bcl-2 ratio in oxidatively stress-induced SH-SY5Y cells. Besides, probiotic Y-CM significantly increased BDNF mRNA expression and decreased Bax/Bcl-2 ratio. The physicochemical properties of probiotic yogurt with H40 was not significantly different from the control yogurt. The viable cell counts of lactic acid bacteria in control and probiotic yogurt with H40 was 8.66 Log CFU/mL and 8.96 Log CFU/mL, respectively. Therefore, these results indicate that H40 can be used as prophylactic functional dairy food having neuroprotective effects.

• Journal of Radiation Industry
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• v.9 no.4
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• pp.187-192
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• 2015

CD44 is a particular adhesion molecule and facilitates both cell-cell and cell-matrix interactions. In particular, splice variants of CD44 are particularly overexpressed in a large number of malignancies and carcinomas. In this study, the $^{177}Lu$-labelled CD44 targeting antibody was prepared and bioevaluated in vitro and in vivo. Anti-CD44 was immunoconjugated with the equivalent molar ratio of cysteine-based DTPA-NCS and radioimmunoconjugated with $^{177}Lu$ at room temperature within 15 minutes. The stability was tested in human serum. An in vitro study was carried out in HT-29 human colon cancer cell lines. For the biodistribution study $^{177}Lu$-labelled anti-CD44 was injected in xenograft mice. Anti-CD44 was immunoconjugated with cysteine-based DTPA-NCS and purified by a centricon filter system having a molecular cut-off of 50 kDa. Radioimmunoconjugation with $^{177}Lu$ was reacted for 15 min at room temperature. The radiolabeling yield was >99%, and it was stable in human serum without any fragmentation or degradation. The radioimmunoconjugate showed a high binding affinity on HT-29 colon cancer cell surfaces. In a biodistribution study, the tumor-to-blood ratio of the radioimmunoconjugate was 43 : 1 at 1 day post injection (p.i) in human colon cancer bearing mice. The anti-CD44 monoclonal antibody for the targeting of colon cancer was effectively radioimmunoconjugated with $^{177}Lu$. The in vitro high immunoactivity of this radioimmunoconjugate was determined by a cell binding assay. In addition, the antibody's tumor targeting ability was demonstrated with very high uptake in tumors. This radioimmunoconjugate is applicable to therapy in human colon cancer with highly expressed CD44.

• Journal of Life Science
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• v.17 no.11
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• pp.1533-1538
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• 2007

This study was carried out to determine the inhibitory effects of solvent extracts from Sargassum hemiphyllum on growth of cancer cell lines (AGS human gastric adenocarcinoma and HT-29 human colon cancer cells) and production of lipid peroxides. Inhibitory effects of acetone with methylene chloride extract from S. hemiphyllum on the growth of AGS and HT-29 cancer cells were increased as dose dependent patterns (p<0.05). The methanol extract was more effective on inhibition of growth of AGS. The treatments of hexane, 85% aq. methanol, butanol and water fractions significantly inhibited the growth of cancer cells (p<0.05) and the inhibitory effect was stronger in HT-29. In DCFH-DA (dichlorodihydrofluorescin diacetate) assay, acetone with methylene chloride and methanol extracts showed a stronger inhibitory effect on the production of cellular lipid peroxides (p<0.05) compared with the butanol and hexane fractions. These results indicate that the consumption of S. hemiphyllum may be recommended as a potent functional food for preventing cellular oxidation and cancer.

• Journal of Life Science
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• v.29 no.11
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• pp.1227-1234
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• 2019

Prunus mume, also known as maesil, is a popular fruit consumed in East Asia (Korea, Japan, and China). It contains high amounts of organic acids, minerals, and polyphenols and has been used as a medication for fever, vomiting, and detoxification. In this study, the anti-proliferative and apoptotic effects of solvent fractions from maesil were evaluated using sulforhodamine B (SRB) assays, morphological evaluations, Hoechst 33258 staining, and western blotting. Addition of the maesil methanol fraction (MMF) and the maesil butanol fraction (MBF) significantly and dose-dependently decreased the cell viability of HT-29 human colon cancer cells. Colony-forming assays confirmed that the MMF and MBF treatments decreased colony numbers when compared with untreated control cells. Treatment of HT-29 cells with MMF and MBF caused a distortion of the cell morphology to a shrunken cell mass. Treatment with MMF and MBF also dose-dependently increased nuclear condensation and the formation of apoptotic bodies in HT-29 cells. Treatment with MMF and MBF significantly and dosedependently increased the expression of Bax (a pro-apoptotic protein), caspase-3, and poly ADP-ribose polymerase (PARP) and decreased the expression of Bcl-2 (an anti-apoptotic protein). MMF significantly and dose-dependently inhibited cell proliferation induced by bisphenol A, an environmental hormone. Therefore, MMF may have potential use as a functional food and as a possible therapeutic agent for the prevention of colon cancer.

• Journal of Life Science
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• v.19 no.9
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• pp.1251-1257
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• 2009

We investigated the growth inhibitory effect of internal organs of Todarodes pacificus (TP) on proliferation in human cancer cell lines in vitro. The internal organs of TP were extracted with methanol (TPM), which was then further fractionated into four subfractions by using a solvent partition method, resulting in hexane (TPMH), methanol (TPMM), butanol (TPMB), and aqueous (TPMA) soluble fractions. We determined the cytotoxic effect of these four fractions in three kinds of cancer cell lines - HepG2, MCF-7 and HT-29 - by MTT assay. Among the four subfractions of TPM, TPMH showed the strongest cytotoxic effects at a concentration of $300{\mu}g$/ml, displaying 91.56% on the HepG2 cell line and 85.93% on the MCF-7 cell line. Morphological changes such as membrane shirinking and blebbing of cells were also observed during TPMH treatment of HepG2 cells. In addition, we also observed quinone reductase (QR) induced effect in the methanol (TPMM) layer of HepG2 cells. TPMM showed the highest induction activity of quinone reductase on HepG2 cells among the other partition layers. The QR induced effect of TPMM was determined to be 2.7 at a level of $360{\mu}g$/ml with a control value of 1.0. Although further studies are needed, the present work suggests that internal organs of Todarodes pacificus (TP) may be a chemopreventive agent for the treatment of human cells.

• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1482-1489
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• 2009

In this study, we investigated the anti-proliferative effect of polysaccharides from Salicornia herbacea on HT-29 human colon cancer cells. Crude polysaccharides from S. herbacea (CS) were prepared by extraction with hot steam water, and fine polysaccharides from S. herbacea (PS) were obtained through further size exclusion chromatography. The anti-proliferative effect of CS and PS were measured using the MTS assay, apoptosis analysis, cell cycle analysis, and RT-PCR. HT-29 cells were treated with CS or PS at different dosages (0.5, 1, 2, 4 mg $ml^{-1}$) for 24 or 48 h. CS and PS inhibited proliferation and stimulated apoptosis of cells in a dose-dependent manner. Flow cytometric analysis after Annexin V-FITC and PI staining revealed that treatment with CS or PS increased total apoptotic death of cells to 24.99% or 91.59%, respectively, in comparison with the control (13.51 %). PS increased early apoptotic death substantially - up to 12 times more than the control. Treatment with CS or PS resulted in a concentration-dependent increase of the G2/M cell population of the cell cycle as determined by flow cytometry. G2/M arrest was induced significantly with the highest concentration (4 mg $ml^{-1}$) of PS. RT-PCR was performed to study the correlation between G2/M arrest and transcription of cell cycle control genes. The anti-proliferative activity of CS and PS was accompanied by inhibition of cyclin B1, and Cdc 2 mRNA. Moreover, both CS and PS induced expression of the p53 tumor suppressor gene and the Cdk inhibitor p21. These results suggest that polysaccharides from S. herbacea have anti-cancer activity in human colon cancer cells.