• Biomolecules & Therapeutics
• /
• 제24권3호
• /
• pp.320-327
• /
• 2016

Columbianadin (CBN), a natural coumarin from Angelica decursiva (Umbelliferae), is known to have various biological activities including anti-inflammatory and anti-cancer effects. In this study, the anti-proliferative mechanism of actions mediated by CBN was investigated in HCT-116 human colon cancer cells. CBN effectively suppressed the growth of colon cancer cells. Low concentration (up to $25{\mu}M$) of CBN induced apoptosis, and high concentration ($50{\mu}M$) of CBN induced necroptosis. The induction of apoptosis by CBN was correlated with the modulation of caspase-9, caspase-3, Bax, Bcl-2, Bim and Bid, and the induction of necroptosis was related with RIP-3, and caspase-8. In addition, CBN induced the accumulation of ROS and imbalance in the intracellular antioxidant enzymes such as SOD-1, SOD-2, catalase and GPx-1. These findings demonstrate that CBN has the potential to be a candidate in the development of anti-cancer agent derived from natural products.

• Molecules and Cells
• /
• 제44권10호
• /
• pp.710-722
• /
• 2021

Hypoxia, or low oxygen tension, is a hallmark of the tumor microenvironment. The hypoxia-inducible factor-1α (HIF-1α) subunit plays a critical role in the adaptive cellular response of hypoxic tumor cells to low oxygen tension by activating gene-expression programs that control cancer cell metabolism, angiogenesis, and therapy resistance. Phosphorylation is involved in the stabilization and regulation of HIF-1α transcriptional activity. HIF-1α is activated by several factors, including the mitogen-activated protein kinase (MAPK) superfamily. MAPK phosphatase 3 (MKP-3) is a cytoplasmic dual-specificity phosphatase specific for extracellular signal-regulated kinase 1/2 (Erk1/2). Recent evidence indicates that hypoxia increases the endogenous levels of both MKP-3 mRNA and protein. However, its role in the response of cells to hypoxia is poorly understood. Herein, we demonstrated that small-interfering RNA (siRNA)-mediated knockdown of MKP-3 enhanced HIF-1α (not HIF-2α) levels. Conversely, MKP-3 overexpression suppressed HIF-1α (not HIF-2α) levels, as well as the expression levels of hypoxia-responsive genes (LDHA, CA9, GLUT-1, and VEGF), in hypoxic colon cancer cells. These findings indicated that MKP-3, induced by HIF-1α in hypoxia, negatively regulates HIF-1α protein levels and hypoxia-responsive genes. However, we also found that long-term hypoxia (>12 h) induced proteasomal degradation of MKP-3 in a lactic acid-dependent manner. Taken together, MKP-3 expression is modulated by the hypoxic conditions prevailing in colon cancer, and plays a role in cellular adaptation to tumor hypoxia and tumor progression. Thus, MKP-3 may serve as a potential therapeutic target for colon cancer treatment.

• Biomolecules & Therapeutics
• /
• 제30권5호
• /
• pp.447-454
• /
• 2022

Few studies have evaluated the role of autophagy in the development of oxaliplatin (OXT) resistance in colon cancer cells. In this study, we compared the role of autophagy between SNU-C5 colon cancer cells and OXT-resistant SNU-C5 (SNU-C5/OXTR) cells. At the same concentration of OXT, the cytotoxicity of OXT or apoptosis was significantly reduced in SNU-C5/OXTR cells compared with that in SNU-C5 cells. Compared with SNU-C5 cells, SNU-C5/OXTR cells exhibited low levels of autophagy. The expression level of important autophagy proteins, such as autophagy-related protein 5 (Atg5), beclin-1, Atg7, microtubule-associated proteins 1A/1B light chain 3B I (LC3-I), and LC3-II, was significantly lower in SNU-C5/OXTR cells than that in SNU-C5 cells. The expression level of the autophagy-essential protein p62 was also lower in SNU-C5/OXTR cells than in SNU-C5 cells. In SNU-C5/OXTR cells, the production of intracellular reactive oxygen species (ROS) was significantly higher than that in SNU-C5 cells, and treatment with the ROS scavenger N-acetylcysteine restored the reduced autophagy levels. Furthermore, the expression of antioxidant-related nuclear factor erythroid 2-related factor 2 transcription factor, heme oxygenase-1, and Cu/Zn superoxide dismutase were also significantly increased in SNU-C5/OXTR cells. These findings suggest that autophagy is significantly reduced in SNU-C5/OXTR cells compared with SNU-C5 cells, which may be related to the production of ROS in OXT-resistant cells.

• Biomolecules & Therapeutics
• /
• 제30권3호
• /
• pp.257-264
• /
• 2022

Colorectal cancer (CRC) is one of the most common malignant tumor. 5-FU is commonly used for the treatment of CRC. However, the development of drug resistance in tumor chemotherapy can seriously reduce therapeutic efficacy of 5-FU. Recent data show that FoxM1 is associated with 5-FU resistance in CRC. FoxM1 plays a critical role in the carcinogenesis and drug resistance of several malignancies. It has been reported that urushiol V isolated from the cortex of Rhus verniciflua Stokes is cytotoxic to several types of cancer cells. However, the underlying molecular mechanisms for its antitumor activity and its potential to attenuate the chemotherapeutic resistance in CRC cells remain unknown. Here, we found that urushiol V could inhibit the cell proliferation and induced S-phase arrest of SW480 colon cancer cells. It inhibited protein expression level of FoxM1 through activation of AMPK. We also investigated the combined effect of urushiol V and 5-FU. The combination treatment reduced FoxM1 expression and consequently reduced cell growth and colony formation in 5-FU resistant colon cancer cells (SW480/5-FUR). Taken together, these result suggest that urushiol V from Rhus verniciflua Stokes can suppress cell proliferation by inhibiting FoxM1 and enhance the antitumor capacity of 5-FU. Therefore, urushiol V may be a potential bioactive compound for CRC therapy.

• Nutrition Research and Practice
• /
• 제6권5호
• /
• pp.396-404
• /
• 2012

The aim of the study was to investigate the inhibitory effects of calcium against intestinal cancer in vitro and in vivo. We first investigated the effects of calcium treatment in HCT116 and HT29 human colon cancer cells. At the concentration range of 0.8-2.4 mM, calcium significantly inhibited cell growth (by 9-29%), attachment (by 12-26%), invasion (by 15-31%), and migration (by 19-61%). An immunofluorescence microscope analysis showed that the treatment with calcium (1.6 mM) for 24 h increased plasma membrane ${\beta}$-catenin but decreased nuclear ${\beta}$-catenin levels in HT29 cells. We then investigated the effect of dietary calcium on intestinal tumorigenesis in $Apc^{Min/+}$ mice. Mice received dietary treatment starting at 6 weeks of age for the consecutive 8 weeks. The basal control diet contained high-fat (20% mixed lipids by weight) and low-calcium (1.4 mg/g diet) to mimic the average Western diet, while the treatment diet contained an enriched level of calcium (5.2 mg calcium/g diet). The dietary calcium treatment decreased the total number of small intestinal tumors (by 31.4%; P < 0.05). The largest decrease was in tumors which were ${\geq}$ 2 mm in diameter, showing a 75.6% inhibition in the small intestinal tumor multiplicity (P < 0.001). Immunohistochemical analysis showed significantly reduced nuclear staining of ${\beta}$-catenin (expressed as nuclear positivity), but increased plasma membrane staining of ${\beta}$-catenin, in the adenomas from the calcium-treated groups in comparison to those from the control group (P < 0.001). These results demonstrate intestinal cancer inhibitory effects of calcium both in human colon cancer cells and $Apc^{Min/+}$ mice. The decreased ${\beta}$-catenin nuclear localization caused by the calcium treatment may contribute to the inhibitory action.

• Toxicological Research
• /
• 제31권2호
• /
• pp.151-156
• /
• 2015

5-Fluorouracil (5-FU) is commonly used for the therapy of colon cancer; however, acquired resistance to 5-FU is a critical barrier to successful treatment and the primary cause of chemotherapy failure. Epithelial-mesenchymal transition (EMT) is a process whereby cells undergo alterations in morphology and molecular characteristics promoting tumor progression and metastasis. Accumulating evidence shows that transition from epithelial to mesenchymal phenotype in cancer cells is associated with their resistance to chemotherapy. However, it is still poorly understood whether EMT is involved in acquired resistance to 5-FU. In this study, we developed an in vitro cell model, 5-FU-resistant HT-29 colon cancer cells, and characterized the differences in cellular morphology and molecular alterations between parental and resistant cells. In accord with mesenchymal-like morphology of 5-FU-resistant HT-29 cells, the expression of the mesenchymal marker fibronectin was significantly increased in these cells in comparision with that in the parental cells. Of interest, we also found a marked increase in the expression of EMT-inducing transcription factors Twist, Zeb1, and Zeb2. Finally, 5-FU-resistant cells showed enhanced migration in comparison with parental HT-29. Taken together, these results indicate that EMT could be associated with 5-FU resistance acquired by HT-29 cells. A specific role of each transcription factor found in this study will require further investigation.

• 한국미생물·생명공학회지
• /
• 제41권3호
• /
• pp.379-382
• /
• 2013

Rhanella aquatilis AY2000 균주가 생산하는 일종의 당단백질인 항효모성 물질 (AYS)에 대한 항암활성을 조사하기 위해 in vitro에서 암세포에 대한 AYS의 세포독성을 조사하였다. 그 결과 AYS는 인체의 Jurkat T 세포와 마우스의 sarcoma 180 세포에 대해서는 세포독성을 나타내지 않았으나, 인체 대장암세포인 colon cancer TH20 세포에는 세포독성을 나타내었다. 또한 이 AYS는 62.5에서 500 ${\mu}g/ml$까지 농도의존적으로 인체대장암세포에 대해 세포독성을 증가시켰다. 뿐만 아니라 이 AYS와 시판 항암제를 혼합하여 처리한 결과 시판 항암제를 단독으로 처리한 것 보다 인체대장암세포에 대한 항암효과가 더욱 상승되었다.

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

• 대한본초학회지
• /
• 제21권4호
• /
• pp.51-58
• /
• 2006

Objectives : In this study, we investigate that Ulmi cortex extract contributes to growth inhibitory effect and anti-cancer activity on the HT-29 human colon cancer cells. Methods : Ulmi cortex was extracted from the leaves of the plant using water. The Ulmi cortex extract was treated to different concentrations for 24 hr. Growth inhibitory effect was analyzed by measuring FACS study and MTT assay. Cell cycle inhibition was confirmed by kinases assay. Cell apoptosis was confirmed by surveying caspases cascades activation using Western blot. Results : Exposure to Ulmi cortex extract (0.4mg/ml) results in an inhibitory effect on cell growth in HT-29 cells. Growth inhibition by Ulmi cortex extract in HT-29 cells was related with the inhibition of proliferation and induction of apoptosis. The Ulmi cortex extract induces G1-cell cycle arrest and DNA fragmentation in HT-29 cells. Furthermore, Ulmi cortex extract induces cell apoptosis through the activation of caspases-3 and PARP cleavage. Conclusion : Ulmi cortex extract induces apoptosis in human colon cancer cells, therefore, we suggest that Ulmi cortex extract can be used as a novel class of anti-cancer drugs.

• Journal of Nutrition and Health
• /
• 제36권3호
• /
• pp.280-286
• /
• 2003

Conjugated linoleic acid (CLA) consists of several geometric isomers of linoleic acid. CLA is found in foods derived from ruminants and exhibits strong anticarcinogenic effects in a variety of animal models. Matrix metalloproteinases (MMPs) play a key role in cancer progression. Specifically, MMP-2 and -9, which hydrolyze the basal membrane type IV collagen, are involved in the initial breakdown of collagen and basement membrane components during tumor growth and invasion. However, the effects of CLA on cancer cell motility and MMP expression and activity are not currently well known. Therefore, the present study examined whether CLA reduces the activity of MMP and cell motility in SW480 and SW620 cells, the human colon cancer cell lines. Gelatin zymography and Western blot analysis revealed that phorbol 12-myristate 13-acetate (PMA) induced the activity and protein expression of Mr 92,000 MMP-9 in both cell lines. To examine whether CLA inhibits the MMP activity, cells were incubated with 100 ngfmL PMA in the presence of various concentrations of CLA. PMA-induced MMP-9 activity was decreased by 20 $\mu$ M CLA in SW480 cells, and by 10 $\mu$ M and 20 $\mu$ M CLA in SW620 cells. Results from the Hoyden chamber assay showed that cell motility was increased by PMA and that PMA-induced cell motility was significantly decreased by 20 $\mu$ M CLA in SW480 cells. These results indicate that CLA may reduce the motility and MMP activity in human colon cancer cells.