• The Korean Journal of Physiology and Pharmacology
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• 제22권1호
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• pp.53-61
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• 2018

Ethyl linoleate is an unsaturated fatty acid used in many cosmetics for its various attributes, such as antibacterial and anti-inflammatory properties and clinically proven to be an effective anti-acne agent. In this study, we investigated the effect of ethyl linoleate on the melanogenesis and the mechanism underlying its action on melanogenesis in B16F10 murine melanoma cells. Our results revealed that ethyl linoleate significantly inhibited melanin content and intracellular tyrosinase activity in ${\alpha}$-MSH-induced B16F10 cells, but it did not directly inhibit activity of mushroom tyrosinase. Ethyl linoleate inhibited the expression of microphthalmia-associated transcription factor (MITF), tyrosinase, and tyrosinase related protein 1 (TRP1) in governing melanin pigment synthesis. We observed that ethyl linoleate inhibited phosphorylation of Akt and glycogen synthase kinase $3{\beta}$ ($GSK3{\beta}$) and reduced the level of ${\beta}-catenin$, suggesting that ethyl linoleate inhibits melanogenesis through $Akt/GSK3{\beta}/{\beta}-catenin$ signal pathway. Therefore, we propose that ethyl linoleate may be useful as a safe whitening agent in cosmetic and a potential therapeutic agent for reducing skin hyperpigmentation in clinics.

• Molecules and Cells
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• 제20권2호
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• pp.256-262
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• 2005

The neuronal cytoskeleton is essential for establishment of neuronal polarity, but mechanisms controlling generation of polarity in the cytoskeleton are poorly understood. The nonreceptor tyrosine kinase, Fer, has been shown to bind to microtubules and to interact with several actin-regulatory proteins. Furthermore, Fer binds p120 catenin and has been shown to regulate cadherin function by modulating cadherin-${\beta}$-catenin interaction. Here we show involvement of Fer in neuronal polarization and neurite development. Fer is concentrated in growth cones together with cadherin, ${\beta}$-catenin, and cortactin in stage 2 hippocampal neurons. Inhibition of Fer-p120 catenin interaction with a cell-permeable inhibitory peptide (FerP) increases neurite branching. In addition, the peptide significantly delays conversion of one of several dendrites into an axon in early stage hippocampal neurons. FerP-treated growth cones also exhibit modified localization of the microtubule and actin cytoskeleton. Together, this indicates that the Fer-p120 interaction is required for normal neuronal polarization and neurite development.

• Molecular & Cellular Toxicology
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• 제5권4호
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• pp.328-334
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• 2009

TBX3 has demonstrated oncogenic activity as a downstream target of the Wnt/$\beta$-catenin signaling pathway. In this study, the aim was to determine whether overexpression of the TBX3 protein is involved in the development and/or progression of gastric cancers. We analyzed the expression pattern of the TBX3 and $\beta$-catenin proteins in a series of 186 sporadic gastric cancers. Altered expression of the TBX3 and $\beta$-catenin proteins was observed in 54 (29.0%) and 48 (25.8%) of the 186 gastric cancers. Statistically, overexpression of the TBX3 and $\beta$-catenin proteins was not associated with the clinical and pathological parameters studied including: histological type, tumor location, tumor size, and the 5-year survival (P>0.05). However, TBX3 overexpression was closely associated with lymph node metastasis and aberrant $\beta$-catenin expression (P<0.05). In addition, overexpression of the TBX3 protein was confirmed by Western blot analysis of primary gastric cancer tissues and cell lines. These data suggest that TBX3 overexpression may play a role in the development and progression of sporadic gastric cancers.

• Asian Pacific Journal of Cancer Prevention
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• 제16권15호
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• pp.6549-6556
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• 2015

The PI3K-Akt-mTOR, $Wnt/{\beta}$-catenin and apoptosis signaling pathways have been shown to be involved in genesis of colorectal cancer (CRC). The aim of this study was to elucidate whether combination of Gelam honey and ginger might have chemopreventive properties in HT29 colon cancer cells by modulating the mTOR, $Wnt/{\beta}$-catenin and apoptosis signaling pathways. Treatment with Gelam honey and ginger reduced the viability of the HT29 cells dose dependently with $IC_{50}$ values of 88 mg/ml and 2.15 mg/ml respectively, their while the combined treatment of 2 mg/ml of ginger with 31 mg/ml of Gelam honey inhibited growth of most HT29 cells. Gelam honey, ginger and combination induced apoptosis in a dose dependent manner with the combined treatment exhibiting the highest apoptosis rate. The combined treatment downregulated the gene expressions of Akt, mTOR, Raptor, Rictor, ${\beta}$-catenin, $Gsk3{\beta}$, Tcf4 and cyclin D1 while cytochrome C and caspase 3 genes were shown to be upregulated. In conclusion, the combination of Gelam honey and ginger may serve as a potential therapy in the treatment of colorectal cancer through inhibiton of mTOR, $Wnt/{\beta}$ catenin signaling pathways and induction of apoptosis pathway.

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

• Molecules and Cells
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• 제22권3호
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• pp.353-359
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• 2006

The bone morphogenetic protein (BMP) family has been implicated in control of cartilage development. Here, we demonstrate that BMP-2 promotes chondrogenesis by activating p38 mitogen-activated protein kinase (MAPK), which in turn downregulates $Wnt-7a/{\beta}$-catenin signaling responsible for proteasomal degradation of Sox9. Exposure of mesenchymal cells to BMP-2 resulted in upregulation of Sox9 protein and a concomitant decrease in the level of ${\beta}$-catenin protein and Wnt-7a signaling. In agreement with this, the interaction of Sox9 with ${\beta}$-catenin was inhibited in the presence of BMP-2. Inhibition of the p38 MAPK pathway using a dominant negative mutant led to sustained Wnt-7a signaling and decreased Sox9 expression, with consequent inhibition of precartilage condensation and chondrogenic differentiation. Moreover, overexpression of ${\beta}$-catenin caused degradation of Sox9 via the ubiquitin/26S proteasome pathway. Our results collectively indicate that the increase in Sox9 protein resulting from downregulation of ${\beta}$-catenin/Wnt-7a signaling is mediated by p38 MAPK during BMP-2 induced chondrogenesis in chick wing bud mesenchymal cells.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제27권1호
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• pp.62-70
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• 2024

Purpose: Choledochal cysts are congenital anomalies that occur as localized cystic or fusiform dilatations of the biliary tree. Reflux and stasis of pancreatic enzymes in the biliary duct may relate to the development of intestinal metaplasia which might be an important factor related to the carcinogenesis of choledochal cyst, thus the expression of beta-catenin in the metaplastic epithelium might be associated with malignant transformation of choledochal cyst epithelium. Methods: This study was conducted at a tertiary care pediatric center between October 2014 and March 2017. Forty patients were evaluated for epithelial lining, mural ulceration, fibrosis, inflammation, and metaplasia. Results: Out of 40, 12 cases (30.0%) were the infantile age group and 28 cases (70.0%) were in the classic pediatric group. Ulceration was classified as grade 0 (14 cases, 35.0%), grade 1 (17 cases, 42.5%), or grade 2 (nine cases, 22.5%). Inflammation was classified as grade 0 (2 cases, 5.0%), grade 1 (26 cases, 65.0%), or grade 2 (12 cases, 30.0%). Fibrosis was classified as grade 0 (five cases, 12.5%), grade 1 (11 cases, 27.5%), grade 2 (17 cases, 42.5%), or grade 3 (seven cases, 17.5%). Metaplasia was noted in five (12.5%) out of 40 cases. All choledochal cysts with metaplasia showed beta-catenin nuclear positivity on immunohistochemistry and were followed up. Conclusion: This study emphasizes the importance of detailed histopathological examination and documentation of metaplastic changes. Metaplasia was associated with beta-catenin nuclear positivity. These findings suggest a potential role for beta-catenin as a marker of metaplastic changes in choledochal cysts.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제18권2호
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• pp.144-148
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• 2015

Hepatocellular adenomas are a benign, focal, hepatic neoplasm that have been divided into four subtypes according to the genetic and pathological features. The ${\beta}$-catenin activated subtype accounts for 10-15% of all hepatocellular adenomas and specific magnetic resonance imaging features have been defined for different hepatocellular adenomas subtypes. The current study aimed to report the magnetic resonance imaging features of a well differentiated hepatocellular carcinoma that developed on the basis of ${\beta}$-catenin activated hepatocellular adenomas in a child. In this case, atypical diffuse steatosis was determined in the lesion. In the literature, diffuse steatosis, which is defined as a feature of the hepatocyte nuclear factor-$1{\alpha}$-inactivated hepatocellular adenomas subtype, has not been previously reported in any ${\beta}$-catenin activated hepatocellular adenomas case. Interlacing magnetic resonance imaging findings between subtypes show that there are still many mysteries about this topic and larger studies are warranted.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.3583-3587
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• 2012

SUMOylation has emerged as an important post-translational modification that modulates the localization, stability and activity of a broad spectrum of proteins. A dynamic process, it can be reversed by a family of SUMO-specific proteases (SENPs). However, the biological roles of SENPs in mammalian development and pathogenesis remain largely elusive. Here, we demonstrated that SENP2 plays a critical role in the control of hepatocellular carcinoma cell growth. SENP2 was found to be down-regulated in hepatocellular carcinoma (HCC) tissues and over-expression suppressed the growth and colony formation of HCC cells. In contrast, silencing of SENP2 by siRNAs promoted cancer cell growth. We further found that stability of ${\beta}$-catenin was markedly decreased when SENP2 was over-expressed. Interestingly, the decrease was dependent on the de-SUMOylation activity of SENP2, because over-expression of a SENP2 catalytic mutant form had no obviously effects on ${\beta}$-catenin. Our results suggest that SENP2 might play a role in hepatocellular carcinoma cell growth control by modulating the stability of ${\beta}$-catenin.

• BMB Reports
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• 제52권7호
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• pp.451-456
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• 2019

NDRG1 has been reported to exert pivotal roles in tumor progression and metastasis via Wnt/${\beta}$-catenin signaling pathway. However, little is known about the role of NDRG3 in hepatocarcinogenesis despite its classification in the same subfamily of NDRG1. The present study was aimed to characterize the expression pattern and understand the biological roles of NDRG3 in hepatocarcinogenesis, as a means to exploit its therapeutic potential. It was observed that NDRG3 was up-regulated in HCC tissues and higher NDRG3 expression was associated with significantly shorter overall survival. Furthermore, a lower level of NDRG3 exhibited marked positive correlation with metastasis-free survival. In vitro and in vivo experiments revealed that knock-down of NDRG3 inhibits HCC metastasis and angiogenesis. We further demonstrated that activation of WNT/${\beta}$-catenin signaling and enhanced CSC-like properties were responsible for NDRG3-mediated promoting effect on HCC. In conclusion, the principal findings demonstrated that high NDRG3 expression facilitates HCC metastasis via regulating the turnover of ${\beta}$-catenin, as well as provides a potential therapeutic target for future therapeutic interventions.