• 생약학회지
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• 제38권2호통권149호
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• pp.117-122
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• 2007

The specific activation of the immune system to control cancer growth in vivo has been a long-standing goal in cancer immunology. Whole tumor Iysates have been used either alone or combined with adjuvants to induce specific immune response in vivo. Here, we examined whether freezing/thawing (F/T) colon26-M3.1 tumor cell admixed with EN-3, glycoprotein purified from Acanthopanx Senticosus, could stimulate in vivo immunity by using a murine experimental tumor metastasis model produced by colon26-M3.1 carcinoma cells. Vaccination of mice with F/T treated colon26-M3.1 carcinoma cells in combination with EN-3 as an adjuvant resulted in a significant inhibition in tumor metastasis of mice against live colon26-M3.1 carcinoma challenge. In addition, the splenocytes from vaccinated mice exhibited a higher proliferating activity and secreted interferon-${\gamma}$. These results suggest that EN-3 can be applied to immunoadjuvant to enhance the antitumor immunity in vivo.

• Archives of Pharmacal Research
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• 제27권12호
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• pp.1253-1257
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• 2004

6-Methoxydihydrosanguinarine (6ME), a benzophenanthridine alkaloid derived from the methanol extracts of Hylomecon hylomeconoides, showed a dose-dependent effect at 1-10 ${\mu}M$ on causing apoptotic cell death in HT29 colon carcinoma cells $(IC_{50} = 5.0{\pm}0.2 {\mu}M)$. Treatment of HT-29 cells with 6ME resulted in the formation of internucleosomal DNA fragmentation. Treatment of the cells with 6ME caused activation of caspase-3, -8 and 9 protease and subsequent proteolytic cleavage of poly(ADP-ribose)polymerase. 6ME increased the expression of p53 and Bax and decreased the expression of Bid. These results indicate that p53 and proapoptotic Bcl-2 family proteins might participate in the antiproliferative activity of 6ME in HT29 cells.

• Asian Pacific Journal of Cancer Prevention
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• 제14권7호
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• pp.4249-4254
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• 2013

Background: Parafibromin is a protein encoded by the HRPT2 (hyperparathyroidism 2) oncosuppressor gene and its down-regulated expression is involved in pathogenesis of parathyroid, breast, gastric and colorectal carcinomas. This study aimed to clarify the effects of parafibromin expression on the phenotypes and relevant mechanisms of DLD-1 colon carcinoma cells. Methods: DLD-1 cells transfected with a parafibromin-expressing plasmid were subjected to examination of phenotype, including proliferation, differentiation, apoptosis, migration and invasion. Phenotype-related proteins were measured by Western blot. Parafibromin and ki-67 expression was detected by immunohistochemistry on tissue microarrays. Results: The transfectants showed higher proliferation by CCK-8, better differentiation by electron microscopy and ALP activity and more apoptotic resistance to cisplatin by DNA fragmentation than controls. There was no difference in early apoptosis by annexin V, capase-3 activity, migration and invasion between DLD-1 cells and their transfectants. Ectopic parafibromin expression resulted in down-regulated expression of smad4, MEKK, GRP94, GRP78, $GSK3{\beta}$-ser9, and Caspase-9. However, no difference was detectable in caspase-12 and -8 expression. A positive relationship was noted between parafibromin and ki-67 expression in colorectal carcinoma. Conclusions: Parafibromin overexpression could promote cell proliferation, apoptotic resistance, and differentiation of DLD-1 cells.

• Food Science and Biotechnology
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• 제16권2호
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• pp.260-264
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• 2007

Gleditsiae Semen (GS) has been used in both Korea and China as herbal medicine for the treatment of cephalalgia, catharsis, and other diseases. However, the apoptosis of GS against human cancer cells has not previously been investigated. The primary objective of this study was to determine the mechanisms inherent in GS-induced cytotoxicity and apoptosis, using methanolic extract of GS (GSE) in HT-29 human colon carcinoma cells. We found that GSE induced cytotoxicity in HT-29 cells in a dose-dependent manner, and this effect was verified via a lactate dehydrogenase release assay and a colony formation assay. In particular, HT-29 cells showed extensive cell death when treated with $50\;{\mu}g/mL$ of GSE; the calculated $IC_{50}$ value was $20\;{\mu}g/mL$. It induced characteristic apoptotic signs in HT-29 cells, including chromatin condensation and DNA fragmentation, occurring within 6-24 hr when the cells were treated at a concentration of $50\;{\mu}g/mL$. Interestingly, we detected the activation of caspase-3 and -9, but not caspase-8, and apoptotic bodies in GSE-treated HT-29 cells. Collectively, our results indicate that GSE induces apoptosis via a mitochondria-mediated apoptotic pathway, and these findings may be significant with regard to the development of a new drug for the treatment of human colon carcinoma cells.

• BMB Reports
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• 제41권11호
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• pp.803-807
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• 2008

We investigated the expression of muscarinic acetylcholine receptors (mAChRs) and their possible involvement in the regulation of cell proliferation in four colon cancer cell lines (SNU-61, SNU-81, SNU-407, and SNU-1033) derived from Korean colon carcinoma patients. A ligand binding assay showed that all four cell lines expressed mAChRs. Treatment of the four cell lines with the cholinergic agonist carbachol led to the activation of extracellular signal-regulated kinases 1 and 2 (ERK1/2). In SNU-407 cells, carbachol significantly stimulated cell proliferation, which could be abolished by the muscarinic antagonist atropine and the ERK1/2 kinase inhibitor PD98059. These results indicate that mAChRs specifically mediate the proliferation of SNU-407 colon cancer cells via the ERK1/2 pathway.

• 한국식품영양과학회지
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• 제30권2호
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• pp.314-319
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• 2001

In the present study, effects of $\beta$-alanine, a known taurine antagonist for its structural similarity, on the adaptive regulation and kinetic behavior of the taurine transporter were investigated in the HT-29, human colon carcinoma cell line. Pretreatment of the cell with $\beta$-alanine(10mM) for varying periods from 3 to 30 hrs significantly reduced the taurine uptake compared to the value for control cells. This decrease in the taurine transporter activity was dependent on the incubation time with $\beta$-alanine, and the maximal down-regulation of the transporter activity was observed in cells pretreated with $\beta$-alanine for 24 hrs (25% of the control value, p<0.01). The taurine transporter appears to bind exclusively with $\beta$-alanine in the HT-29 cells since the same concentration of $\alpha$-alanine added in the culture medium for 24 hrs did not influence the taurine uptake. Kinetic analyses of the taurine transporter activity was performed in the HT-29 cell line with varying taurine concentration (5~60$\mu$M) in the uptake medium. Active taurine uptake was significantly lower in $\beta$-alanine pretreated cells compared to the value for control cells in the range of taurine concentration used in the experiment (p<0.001). The cells pretreated with $\beta$-alanine showed a 50% lower maximal velocity (Vmax, 1.7$\pm$2.0 nmole.mg $protein^{-1}$.$30min^{-1}$), and a 99% higher Michaelis constant (Km, 40.3$\pm$7.6$\mu$M) than the control values (3.3$\pm$1.9 nmole.mg $protein^{-1}$.$30min^{-1}$, and 20.3$\pm$2.1$\mu$M, respectively). These results on kinetic data suggest that $\beta$-alanine induced down-regulation of the taurine transporter activity was associated with decreases in both maximal velocity and affinity of the transporter.

• Applied Biological Chemistry
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• 제49권3호
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• pp.248-253
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• 2006

조각인(Gleditsiae Semen)은 동아시아 지역에서 장 기능을 향상시키는 등의 여러 가지 민간요법으로 사용되는 한약재이다. 본 연구에서는 조각인의 항암활성을 검색하기 위한 목적으로 methanol, ethanol, acetone으로 추출한 뒤, 인간 유래의 대장암 세포주 HT-29에 처리하여 각 추출물의 암세포 성장 억제능을 확인하기 위하여 MTT-dye reduction assay를 이용하여 실험하였다. 그 결과, methanol 추출물에서 가장 높은 세포독성을 확인할 수 있었고, ethanol 추출물에서도 비교적 높은 암세포 성장 억제능을 볼 수 있었으나, acetone 추출물에서는 거의 세포독성이 나타나지 않았다. 그리고 추출물들을 $25\;{\mu}g/ml$의 농도로 암세포에 처리하여 위상차 현미경으로 세포주의 형태학적 변화를 관찰한 결과에서도 methanol 추출물에서의 활성이 가장 강력하게 나타남을 알 수 있었다. 조각인의 항암활성물질들의 용매특성을 알아보기 위하여 methanol 추출물을 극성도에 따라 용매분획 하여 분리한 각 분획물의 세포독성을 확인한 결과, water층 분획물에서 농도 의존적으로 세포독성을 나타냄을 확인하였다. 또한 조각인의 water층 분획물은 또 다른 대장암 세포주인 SW620에 대해서도 대조군에 비해 $25\;{\mu}g/ml$의 농도에서 2배 정도 높은 항암활성을 나타내고 있음을 MTT reduction assay와 LDH release assay를 통하여 확인 할 수 있었다.

• BMB Reports
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• 제33권5호
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• pp.407-411
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• 2000

The effects of heat shock, or all-trans retinoic acid, on the expression of the C-reactive protein mRNA in the HT-29 human colon carcinoma cells, as well as the functional role of the C-reactive protein as a molecular chaperone, were studied. The expression level of the C-reactive protein mRNA in the HT-29 cells was increased time-dependently when exposed to heat-shock, and dose-dependently when treated with all-trans retinoic acid. The activities of transglutaminase C and K in the HT-29 cells were significantly increased when treated with all-trans retinoic acid. The C-reactive protein prevented thermal aggregation of the citrate synthase and stabilized the target enzyme, citrate synthase. The C-reactive protein promoted functional refolding of the urea-denatured citrate synthase up to 40-70%. These results suggest that the C-reactive protein, which is induced in human colon carcinoma cells, when heated or treated with all-trans retinoic acid has in a part functional activity of the molecular chaperone.

• Archives of Pharmacal Research
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• 제23권2호
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• pp.167-171
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• 2000

We have investigated the in vitro cytotoxic effect of liposome-encapsulated N-(phospho-nacetyl)-L-aspartic acid (PALA) against C-26 murine colon cancer cells, and have compared it in this regard to free PALA. Three different PALA-containing liposomal formulations using distearoylphosphatidylcholine (DSPC), distearoylphosphatidylglycerol (DSPG), and polyethyle-neglycol-derivatized distearoylphosphatidylethanolamine (PEG-DSPE) were made and their cytotoxicity was measured. In 72 hr continuous exposure experiment with C-26 cells, the 50% growth inhibitory concentration ($IC_50$) of DSPG-PALA liposome formulation was $0.09\mu\$, which showed about 65-fold more potent than unencapsulated free PALA ($5.1\mu\$). Similar degree of increase in cytotoxicity was also observed in 1 hr exposure experiment. However the $IC_50$ of PEG-DSPE-PALA liposome and DSPC-PALA liposome were $10.7\mu\$and $11.8\mu\$respectively, which showed slightly less potent than unencapsulated free PALA. Physical characteristics of PALA-liposomes, such as the size and drug:lipid ratio were also determined. In conclusion, negatively-charged DSPG-PALA liposome showed the highest cytotoxic effect among tested on the C-26 cells in vitro.

• Applied Biological Chemistry
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• 제50권3호
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• pp.228-232
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• 2007

본 연구는 만형자(Vitex rotundifolia)의 세포독성을 확인하기 위한 목적으로 methanol, ethanol, acetone으로 추출한 뒤, 인간 유래의 대장암 세포주인 HT-29에 처리하여 MTT reduction assay를 이용하여 실험을 하였다. 그 결과, 모든 만형자 추출물에서 농도 의존적으로 성장 저해 효과가 나타났으며, 그 중에서도 acetone 추출물을 50 ${\mu}g/ml$ 농도로 처리 시 18%로 가장 높은 항암 효과를 보였다. 또한 각 용매별 추출물을 50 ${\mu}g/ml$를 처리하여 HT-29 세포주의 성장을 관찰한 결과, acetone 추출물은 대조구에 비하여 암세포의 수축 등 형태변화가 두드러지게 나타났으며, Hoechst 33342 staining을 통하여 apoptotic body가 형성된 것을 확인 하였다. 그리고 가장 활성이 좋은 acetone 추출물을 용매 분획하여 얻은 분획물 중, n-hexane 분획물에서 농도 의존적으로 세포독성을 나타냄을 알 수 있었다. 또한 만형자의 n-hexane 분획물은 다른 대장암 세포주 SW620에 대해서도 50 ${\mu}g/ml$ 농도에서 대조군에 비하여 7배 정도의 높은 세포독성을 나타내고 있음을 MTT reduction assay와 LDH release assay를 통하여 확인 할 수 있었다.