Capsosiphon fulvescens glycoprotein inhibits AGS gastric cancer cell proliferation by downregulating Wnt-1 signaling

• Published in: International journal of oncology Vol. 43; no. 5; pp. 1395 - 1401
• Main Authors: Kim, Young-Min, Kim, In-Hye, Nam, Taek-Jeong
• Format: Journal Article
• Language: English
• Published: Greece Spandidos Publications UK Ltd 01.11.2013; D.A. Spandidos
• Subjects: Apoptosis; Apoptosis - drug effects; Blotting, Western; Cell adhesion & migration; Cell Adhesion - drug effects; Cell culture; Cell cycle; Cell Cycle - drug effects; Cell growth; Cell Proliferation - drug effects; Chlorophyta - chemistry; Down-Regulation; Gastric cancer; Gene Expression Regulation, Neoplastic - drug effects; Genes; Glycoproteins - metabolism; Humans; Metastasis; Motility; Plant Extracts - pharmacology; Proteins; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - genetics; Signal Transduction; Stomach Neoplasms - metabolism; Stomach Neoplasms - pathology; Stomach Neoplasms - prevention & control; Transcription factors; Tumor Cells, Cultured; Wnt1 Protein - antagonists & inhibitors; Wnt1 Protein - genetics; Wnt1 Protein - metabolism; United States > US
• ISSN: 1019-6439; 1791-2423
• DOI: 10.3892/ijo.2013.2079

Previously, we examined various apoptosis pathways in the AGS gastric cancer cell line using Capsosiphon fulvescens glycoprotein (Cf-GP). In this study, we focused on the downregulation of the Wnt-1 signaling pathway and cell cycle arrest. Upregulation of the Wnt signaling pathway has been observed in various cancer cells. The Wnt signal ligand acts in both canonical and non-canonical pathways. Among them, Wnt-1 was dependent on the canonical pathway. Here, we show inhibition of Wnt-1 signaling, β-catenin and transcription factors in AGS cells via Cf-GP. First, we examined the Frizzled receptor and Wnt-1 signal-related proteins including Axin, LRP, β-catenin, APC and GSK-3β. In addition, the expression levels of transcription factors Tcf/LEF were determined by western blot analysis and RT-PCR. Based on the data, we confirmed downregulation of the Wnt-1 signaling pathway by Cf-GP. Also, we determined the expression levels of cell cycle-related proteins cyclin D and c-myc, and looked for cell cycle arrest by cell cycle test analysis. We found that AGS cells arrested in the G0/G1 phase by Cf-GP. These results provide a mechanism of AGS cell inhibition through the downregulation of Wnt-1 signaling by Cf-GP.