• 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.

• BMB Reports
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• 제32권3호
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• pp.266-272
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• 1999

The insulin-like growth factor (IGF) system consisting of IGF-I, IGF-II, IGF-receptors, and IGF-binding proteins (IGFBP) regulates the proliferation of a variety of cancer cell types. To examine whether a decrease in endogenous IGFBP-3 stimulates proliferation or inhibits differentiation, Caco-2 cells, a human colon adenocarcinoma cell line, were stably transfected with an anti-sense IGFBP-3 expression construct or pcDNA3 vector as control. Accumulation of IGFBP-3 mRNA and secretion of IGFBP-3 into serum-free conditioned medium, 9 days after plating, were significantly lower in Caco-2 cell clones transfected with anti-sense IGFBP-3 cDNA compared to the controls. The anti-sense clones grew at a similar rate to the controls for 8 days after plating, but achieved a higher final density between days 10 and 12. The levels of sucrase-isomaltase mRNA, a marker of enterocyte differentiation of Caco-2 cells, were lower in the anti-sense clones examined on day 9. In conclusion, proliferation of Caco-2 cells can be stimulated by lowering endogenously-produced IGFBP-3.

• Asian Pacific Journal of Cancer Prevention
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• 제13권12호
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• pp.6349-6355
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• 2012

Previous studies showed that Math1 homologous to human Hath1 can cause mouse goblet cells to differentiate. In this context it is important that the majority of colon cancers have few goblet cells. In the present study, the potential role of Hath1 in colon carcinogenesis was investigated. Sections of paraffin-embedded tissues were used to investigate the goblet cell population of normal colon mucosa, mucosa adjacent colon cancer and colon cancer samples from 48 patients. Hath1 and Muc2 expression in these samples were tested by immunohistochemistry, quantitative real-time reverse transcription -PCR and Western blotting. After the recombinant plasmid, pcDNA3.1(+)-Hath1 had been transfected into HT29 colon cancer cells, three clones were selected randomly to test the levels of Hath1 mRNA, Muc2 mRNA, Hath1, Muc2, cyclin D1 and p27 by quantitative real-time reverse transcription-PCR and Western blotting. Moreover, the proliferative ability of HT29 cells introduced with Hath1 was assessed by means of colony formation assay and xenografting. Expression of Hath1, Muc2, cyclin D1 and p27 in the xenograft tumors was also detected by Western blotting. No goblet cells were to be found in colon cancer and levels of Hath1 mRNA and Hath1, Muc2 mRNA and Muc2 were significantly down-regulated. Hath1 could decrease cyclin D1, increase p27 and Muc2 in HT29 cells and inhibit their proliferation. Hath1 may be an anti-oncogene in colon carcinogenesis.

• Asian Pacific Journal of Cancer Prevention
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• 제15권21호
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• pp.9159-9164
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• 2014

Background: In this study eugenol (EU) loaded nanoemulsions (NEs) emulsified with modified starch were prepared and their apoptotic potential against liver and colon cancer cells was examined in comparison with bulk EU. Materials and Methods: We prepared stable EU loaded NEs whcih were characterized by dynamic light scattering, centrifugation and gas chromatography. Furthermore, cell viability was determined using MTT assay, and apoptosis and cell cycle analysess by flow cytometry. Results: HB8065 (liver) and HTB37 (colon) cells when treated with EU:CA NEs demonstrated greater apoptotic cells percentages as evidenced by microscopic images and flow cytometric evaluations. It was observed that EU and EU:CA NE induced apoptosis in both cell lines via reactive oxygen species (ROS) generation. Conclusions: The present study demonstrated that ROS plays a critical role in EU and EU:CA NE induced apoptosis in HB8065 and HTB37 cells. This is the first report on the antiproliferative mechanisms of EU loaded NE.

• Biomolecules & Therapeutics
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• 제15권2호
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• pp.95-101
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• 2007

Resveratrol (3,5,4’-trihydroxy-trans-stilbene), a naturally occurring phytoallexin abundant in grapes and several plants, has been shown to be active in inhibiting proliferation and inducing apoptosis in several human cancer cell lines. On the line of the biological activity of resveratrol, a variety of resveratrol analogs were synthesized and evaluated for their growth inhibitory effects against several human cancer cell lines. In the present study, we found that one of the resveratrol analogs, 3,4,5-trimethoxy-4’-bromo-cis-stilbene, markedly suppressed human colon cancer cell proliferation (EC$_{50}$ = 0.01 ${\mu}$g/ml), and the inhibitory activity was superior to its corresponding trans-isomer (EC$_{50}$ = 1.6 ${\mu}$g/ml) and resveratrol (EC$_{50}$ = 18.7 ${\mu}$g/ml). Prompted by the strong growth inhibitory activity in cultured human colon cancer cells (Col2), we investigated its mechanism of action. 3,4,5-Trimethoxy-4’-bromo-cis-stilbene induced arrest of cell cycle progression at G2/M phase and increased at sub-G1 phase DNA contents of the cell cycle in a time- and dose-dependent manner. Colony formation was also inhibited in a dose-dependent manner, indicating the inhibitory activity of the compound on cell proliferation. Moreover, the morphological changes and condensation of the cellular DNA by the treatment of the compound were well correlated with the induction of apoptosis. These data suggest the potential of 3,4,5-trimethoxy-4’-bromo-cis-stilbene might serve as a cancer chemotherapeutic or chemopreventive agent by virtue of arresting the cell cycle and inducing apoptosis for the human colon cancer cells.

• 한국식품영양과학회지
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• 제33권4호
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• pp.633-640
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• 2004

녹차분말을 포함하는 차가버섯 조성물의 수용성 추출물에 의한 인체 위암 세포 AGS 및 대장암 세포 HCT-15, 그리고 마우스 정상세포 NIH3T3 fibroblast의 세포생육에 미치는 효과를 세포 수 측정방법과 MTT assay 방법으로 측정하였다. 차가버섯 조성물의 수용성 추출물은 인체 대장암 세포주 HCT-15와 위암 세포주 AGS의 생육을 억제하였다. 그러나 동일한 실험조건 하에서 마우스 정상 세포주 NIH3T3은 80% 이상의 생존율을 나타내었다. 본 연구의 결과로 차가버섯 조성물의 수용성 추출물은 정상세포에는 독성을 나타내지 않으면서 위암 및 대장암 세포에는 높은 생육억제 효과를 나타냄을 알 수 있었다.

• 산업식품공학
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• 제15권1호
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• pp.64-69
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• 2011

본 실험에서는 대장암 세포 HT-29의 증식을 억제하고 세포 사멸을 유도하는 천연소재 발굴을 목적으로, 오미자(Schizandra chinensis Baillon) 열수 추출물을 이용하여 인체대장암 세포 HT-29의증식에 미치는 영향을 확인하였다. 오미자 열수 추출물이 HT-29 대장암 세포의 apoptosis 유도 효과 및 기전에 미치는 영향을 분자생물학적 방법으로 실험하여 다음과 같은 결론을 얻었다. MTT assay를 통해 인체 대장암세포 HT-29는 오미자 시료농도 0, 1.0, 2.0, 4.0 mg/mL에서 암세포 사멸농도가 각각 0%, 10%, 70%, 88%를 나타내었다. 대장암세포에 오미자 추출물을 처리하고 cell cycle 분석 결과, 시료농도 의존적으로 sub-G1기가 증가하였고, G0/G1기는 감소되는 것을 통해, apoptosis가 일어나 세포 증식을 저해하는 것으로 확인되었다. 대장암세포 핵의 형태학적 변화를 보면, 오미자 추출물 처리 시 농도 의존적으로 세포수가 감소되는 것이 뚜렷이 관찰되었고 cell shrinking, chromatin condensation등 apototic body 등과 같은 형태학적 변화들이 뚜렷하게 관찰되었다. RT- PCR을 통한 유전자 발현은, 오미자 추출물 농도 의존적으로 p53 유전자 발현이 증가되는 것을 통해 대장암세포의 증식억제를 확인할 수 있었다. In vitro 실험에서 오미자 열수추출물이 대장암세포의 성장을 저해하는 효과가 있음을 확인하였으며, 오미자 추출물에 함유된 활성 본체 규명 및 apoptosis를 유도하는 작용기작에 관한 연구가 수행중이다.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.229.1-229.1
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• 2003

The anti proliferative effects of bile acids and their derivatives on HT -29 human colon cancer cells were investigated. Ursodeoxycholic acid (UDCA) and its synthetic derivatives, HS-1030 and HS-1183, and chenodeoxycholic acid (CDCA) and its synthetic derivatives, HS-1199 and HS-1200 were employed for this study. General evaluations focusing on cell cycle were conducted in HT -29 human colon adenocarcinoma cell line (p53 mutant type). (omitted)

• Asian Pacific Journal of Cancer Prevention
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• 제16권18호
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• pp.8563-8566
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• 2016

Colorectal cancer is one of the most common lethal cancer types worldwide. In recent years, widespread and large-scale studies have been done on medicinal plants for anti-cancer effects, including Glycyrrhiza glabra. The aim of this study was to evaluate the effects of an ethanol extract Glycyrrhiza glabra on the expression of HSP90, growth and apoptosis in the HT-29 colon cancer cell line. HT-29 cells were treated with different concentrations of extract (50,100,150, and $200{\mu}g/ml$). For evaluation of cell proliferation and apoptosis, we used MTT assay and flow cytometry technique, respectively. RT-PCR was also carried out to evaluate the expression levels of HSP90 genes. Results showed that Glycyrrhiza glabra inhibited proliferation of the HT-29 cell line at a concentration of $200{\mu}g/ml$ and this was confirmed by the highest rate of cell death as measured by trypan blue and MTT assays. RT-PCR results showed down-regulation of HSP90 gene expression which implied an ability of Glycyrrhiza glabra to induce apoptosis in HT-29 cells and confirmed its anticancer property. Further studies are required to evaluate effects of the extract on other genes and also it is necessary to make an extensive in vivo biological evaluation and subsequently proceed with clinical evaluations.

• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10483-10487
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• 2015

Heptaphylline derivatives are carbazoles in Clausena harmandiana, a medicinal plant that is utilized for headache, stomach ache, and other treatments of illness. The present study examined the effects of heptaphylline and 7-methoxyheptaphylline on apoptosis of human colon adenocarcinoma cells (HT-29 cell line). Quantification of cell viability was performed using cell proliferation assay (MTT assay) and of protein expression through immunoblotting. The results showed that only heptaphylline, but not 7-methoxyheptaphylline, significantly significantly activated cleaved of caspase-3 and poly (ADP-ribose) polymerase (PARP-1) which resulted in HT-29 cell death. We found that heptaphylline activated BH3 interacting-domain death agonist (Bid) and Bak, proapoptotic proteins. In contrast, it suppressed X-linked inhibitor-of-apoptosis protein (XIAP), Bcl-xL and survivin, inhibitors of apoptosis. In addition, heptaphylline inhibited activation of NF-${\kappa}B$/p65 (rel), a regulator of apoptotic regulating proteins by suppressing the activation of Akt and $IKK{\alpha}$, upstream regulators of p65. The findings suggested that heptaphylline induces apoptosis in human colon adenocarcinoma cells.