• Asian Pacific Journal of Cancer Prevention
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• 제14권1호
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• pp.495-498
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• 2013

Epidermal growth factor receptor (EGFR) is over-expressed in several human cancers. This would suggest that inhibition of EGFR is a reasonable approach for cancer treatment. In this study we investigated EGFR blocking and its effects on the mediated signaling such as MAPK and STATb in HT29 cells. For this aim we used FITC-labeled EGFR antisense oligonucleotides encapsulated with PAMAM nanoparticles to inhibit EGFR expression. Cellular uptake of antisense was investigated by fluorescence microscopy and flow cytometry analysis. The effect of EGFR antisense on the expression of EGFR in HT29 cells was examined by real time PCR and Western blots, which showed that antisense encapsulated with PAMAM decreased the level of EGFR mRNA and protein. In addition, real time PCR results confirmed that EGFR inhibition had an effective role in the reduction of EGFR dependent downstream genes. In conclusion, EGFR antisense encapsulated with PAMAM nanoparticles down regulated EGFR and EGFR-mediated genes.

• Journal of Ginseng Research
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• 제46권2호
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• pp.266-274
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• 2022

Colon cancer, the third most frequent occurred cancer, has high mortality and extremely poor prognosis. Ginsenoside, the active components of traditional Chinese herbal medicine Panax ginseng, exerts antitumor effect in various cancers, including colon cancer. However, the detailed molecular mechanism of Ginsenoside in the tumor suppression have not been fully elucidated. Here, we chose the representative ginsenoside Rg3 and reported for the first time that Rg3 induces mitophagy in human colon cancer cells, which is responsible for its anticancer effect. Rg3 treatment leads to mitochondria damage and the formation of mitophagosome; when autophagy is inhibited, the clearance of damaged mitochondria can be reversed. Next, our results showed that Rg3 treatment activates the PINK1-Parkin signaling pathway and recruits Parkin and ubiquitin proteins to mitochondria to induce mitophagy. GO analysis of Parkin targets showed that Parkin interacts with a large number of mitochondrial proteins and regulates the molecular function of mitochondria. The cellular energy metabolism enzyme GAPDH is validated as a novel substrate of Parkin, which is ubiquitinated by Parkin. Moreover, GAPDH participates in the Rg3-induced mitophagy and regulates the translocation of Parkin to mitochondria. Functionally, Rg3 exerts the inhibitory effect through regulating the nonglycolytic activity of GAPDH, which could be associated with the cellular oxidative stress. Thus, our results revealed GAPDH ubiquitination by Parkin as a crucial mechanism for mitophagy induction that contributes to the tumor-suppressive function of ginsenoside, which could be a novel treatment strategy for colon cancer.

• Animal cells and systems
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• 제4권4호
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• pp.389-394
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• 2000

The Tcf-1 (1-cell factor-1) protein binds to the T-cell specific enhancer sequences and plays an architectural role in the assembly of transcriptional machinery. One of the Tcf family proteins, Tcf-4, was found to be an important regulator for colon cancer development where it activates specific genes upon binding to $\beta$-catenin following Wnt signaling. We were interested in the transcriptional regulatory activities of Tcf-1 and Tcf-4 proteins in T-cells and colon cancer cells. Transactivation assay was developed using a reporter plasmid containing luciferase gene under the control of Tcf responsive elements. Luciferase activity was determined following co-transfection of the reporter along with Tcf-1 and/or $\beta$-catenin expressing plasmids. Transcription was significantly induced by $\beta$-catenin expression in all cells. Tcf-1 by itself did not induce transcription in the mature T-cell lines, but overexpressed Tcf-1 greatly activated transcription in the immature T-cell line. In addition, transfected $\beta$-catenin induced apoptosis, but co-transfected Tcf-1 suppressed apoptosis in HEK293 cells. These results suggest that Tcf-1 and $\beta$-catenin differently regulate transcription and apoptosis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권2호
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• pp.97-108
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• 2011

Cancer stem cells have stem cell-like features, such as the ability for self-renewal and differentiation but show unlimited growth because they have the lost normal regulation of cell growth. Cancer stem cells and normal stem cells have similar features. They show high motility, diversity of progeny, robust proliferative potential, association with blood vessels, immature expression profiles, nestin expression, epidermal growth factor (EGF)-receptor expression, phosphatase and tensin homolog (PTEN) expression, hedgehog pathway activity, telomerase activity, and Wnt pathway activity. On the other hand, with cancer cells, some of these signaling pathways are abnormally modified. In 1875, Cohnheim suggested the concept of cancer stem cells. Recently, evidence for the existence of cancer stem cells was identified. In 1994, the cancer stem cells' specific cell surface marker for leukemia was identified. Since then, other specific cell surface markers for cancer stem cells in solid tumors (e.g. breast and colon cancer) have been identified. In oral cancer, studies on cancer stem cells have been performed mainly with squamous cell carcinomas. Oral cancer specific cell surface markers, which are genes strongly expressed in oral cancer and cancer stem cell specific side populations, have been identified. Cancer stem cells are resistant to radiotherapy and chemotherapy. Therefore, to eliminate malignant tumors efficiently and reduce the recurrence rate, therapy targeting cancer stem cells needs to be performed. Currently, studies targeting the cancer stem cells' specific signaling pathways, telomerase and tumor vasculatures are being done.

• 생명과학회지
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• 제24권10호
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• pp.1137-1143
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• 2014

Doxorubicin은 광범위한 암을 치료하는데 사용되는 일반적인 항암제이지만, 내인성 산화질소 생성량과 Doxorubicin의 항암 효과의 상관 관계에 대해서는 아직 명확하게 밝혀지지 않았다. 본 연구에서는 인간 대장암 세포에서 Doxorubicin의 항암 활성에 내인성 산화질소가 미치는 영향을 확인하고자 하였다. HCT116 (p53-WT)과 HT29 (p53-MUT) 세포에서 Doxorubicin 처리에 의해 세포 생존율의 차이를 보였으며, NMA 병행처리는 Doxorubicin의 효과를 감소시켰음을 확인할 수 있었다. 추가 연구를 통해 HCT116과 HT29 세포에서 sub-$G_1$ 기의 세포 빈도와 DNA 단편화의 결과를 통해 내인성 산화질소가 Doxorubicin에 의한 apoptosis를 조절하는 것을 확인하였다. 이러한 결과는 인간 대장암 세포에서 내인성 산화질소와 IAP 발현, p53의 상태에 따른 조절이 Doxorubicin에 의해 유도된다는 것을 보여주며, 이러한 메커니즘은 대장암에서 화학요법의 효율을 향상시키기 위한 전략적인 표적으로 이용할 수 있을 것으로 생각된다.

• Biomolecules & Therapeutics
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• 제16권2호
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• pp.87-94
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• 2008

In view of obtaining potential anticancer compounds, we studied the inhibitory activity and the cytotoxic effects of a candidate compound in cancer cells. The cytotoxic effects of cannabidiol (CBD) in vitro were evaluated in NIH3T3 fibroblasts, B16 melanoma cells, A549 lung cancer cells, MDA-MB-231 breast cancer cells, Lenca kidney cells and SNU-C4 colon cancer cells. The cells were cultured in various concentrations of CBD for 48 h and 25 ${\mu}$M of CBD for 6-36 h. The cells were observed to exhibit inhibitory effects of the cell viability in their growth, and then cytotoxicity was estimated. The inhibitory activity of CBD was increased in all cancer cells and showed especially strong increment in breast cancer cells. The cytotoxicity of CBD increased in a dose- and time-dependent manner with growth inhibition in all cancer cell lines. Also, to assess the membrane toxicity induced by CBD, we investigated lactate dehydrogenase (LDH) release. After treatment with various concentrations of CBD, LDH release rate of cancer cells was accelerated. On the other hand, in the induction of cell death, caspase-3, -8 and -9 activations were detected in cancer cells after treatment with various concentrations of CBD, and CBD effectively induced activity of caspase-3, -8 and -9 in A549 lung cancer cells, MDAMB-231 breast cancer cells and Renca kidney cells. Therefore these results suggest that CBD has a possibility of anticancer agents and anticancer effects against cancer cells by modulation of apoptotic pathway in the range of 5-80 ${\mu}$M concentration.

• 한국식품영양과학회지
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• 제28권1호
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• pp.240-245
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• 1999

Growth inhibitory effect of doenjang(Korean soypaste) methanol extracts in SRB assay using AGS human gastric adenocarcinoma cell, Hep 3B human hepatocellular carcinoma cell and HT 29 human colon cancer cell was studied. The treatment of doenjang methanol extracts(2mg/assay) to the AGS, Hep 3B and HT 29 cancer cells inhibited the growth of the cancer cells by 55%, 60%, and 71%, respectively. Doenjang methanol extracts exhibited the highest inhibitory effect among other soybean fermented foods and original materials in the SRB assay. In addition, to separate active compounds of doenjang methanol extracts, we fractionated the doenjang with hexane, methanol, dichloromethane, ethylacetate and butanol. Growth inhibitory effect on the AGS, Hep 3B, HT 29 and MG 63 cancer cells was the highest in the fractions of dichloromethane and ethylacetate among other solvent fractions of the doenjang. These results showed that some compounds contained in the fractions of dichloromethane and ethylacetate might play a role on the anticanceric effect of doenjang.

• Asian Pacific Journal of Cancer Prevention
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• 제17권5호
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• pp.2637-2641
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• 2016

Tumor necrosis factor ($TNF-{\alpha}$), an inflammatory cytokine that plays an important role in the control of cell proliferation, differentiation, and apoptosis, has previously been used in anti-cancer therapy. However, the therapeutic applications of $TNF-{\alpha}$ are largely limited due to its general toxicity and anti-apoptotic influence. To overcome this problem, the present study focused on the effect of active constituents isolated from a medicinal plant on $TNF-{\alpha}$-induced apoptosis in human colon adenocarcinoma (HT-29) cells. Nimbolide from Azadirachta indica was evaluated for cytotoxicity by methyl tetrazolium 3-[4,5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay and phase contrast microscopy. Effects on apoptotic signaling proteins were investigated using Western blot analysis. Nimbolide showed cytotoxicity against HT-29 cells that was significantly different from the control group (p<0.01), a concentration of $10{\mu}M$ significantly inducing cell death (p<0.01). In combination with $TNF-{\alpha}$, nimbolide significantly enhanced-induced cell death. In apoptotic pathway, nimbolide activated c-Jun N-terminal kinase (JNK) phosphorylation, BH3 interacting-domain death agonist (Bid) and up-regulated the death receptor 5 (DR5) level. In the combination group, nimbolide markedly sensitized $TNF-{\alpha}$-induced JNK, Bid, caspase-3 activation and the up-regulation of DR5. Our findings overall indicate that nimbolide may enhance $TNF-{\alpha}$-mediated cellular proliferation inhibition through increasing cell apoptosis of HT-29 cells by up-reglation of DR5 expression via the JNK pathway.

• Nuclear Medicine and Molecular Imaging
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• 제41권3호
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• pp.263-264
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• 2007

Splenic metastasis from colon carcinoma are rare and usually occur in the presence of disseminated visceral metastasis. The liver is the most common site of metastatic spread from colon cancer. Several hypotheses have attempted to explain the low incidence of splenic metastasis. It should be difficult for colorectal cancer cells to reach the spleen through the portal venous system, in which the blood flow is usually from the spleen to the liver. Reticuloendothelial system or rhythmic contraction of the spleen may squeeze out the tumor in the spleen. The absence of afferent lymphatic to the spleen, phagocytic activity and humoral anticancer substances are considered to be other reason for low incidence of splenic metastasis. We report the case of $^{18}F-FDG$ PET/CT finding in a 70-year-old woman who develop isolated splenic metastasis of sigmoid colon cancer.

• Asian Pacific Journal of Cancer Prevention
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• 제17권1호
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• pp.73-80
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• 2016

Colorectal cancer is a very prevalent diagnosed cancer. The current study was performed in order to examine the role of BRAE (Basella rubra aqueous extract) in regulating aberrant crypt foci (ACF) formation, cell proliferation and inhibition of apoptosis in a colon carcinogenesis model in male Wistar rats. Rats were randomly allocated into six groups. Group I served as control, and group II acted as a drug control administered BRAE (250mg/kg b.w.) orally for 30 weeks. Rats in group III-VI were given subcutaneous injections of DMH (25mg/kg b.w. weekly) for 15 weeks to initiate colon carcinogenesis. Those in group IV and VI were administered BRAE along with DMH injections. Rats in group V were administered with BRAE after cessation of DMH injection. After 30 weeks of experimental period colons were obtained from experimental groups and analyzed for ACF incidence, argyrophilic nucleolar organizing region-associated proteins (AgNOR) count, histopathological and immunohistochemical changes. Only in DMH exposed groups were ACF and AgNOR numbers increased. Administration of BRAE appreciably decreased the numbers of ACF and AgNOR in BRAE treated groups. Histopathological findings revealed a high level of dysplastic changes with decreased number of goblet cells found only in only DMH injected rats. Administration of BRAE in treated group rats reversed these changes. Expression markers for cell proliferation (PCNA and Ki67) were elevated in DMH treated rats, but reduced with BRAE treatement. This expression was reversed with apoptosis markers (p53 and Caspase-3). Thus the results results of the present study were found to be significant and confirmed the potential efficacy of BRAE against colon carcinogenesis.