Journal Article

FUT8 promotes breast cancer cell invasiveness by remodeling TGF-β receptor core fucosylation

Yang, Ruey-Bing, Tu, Cheng-Fen, Lin, Yuh-Charn, Kannagi, Reiji, Wu, Meng-Ying

2017

Overview

Background Core fucosylation (addition of fucose in α-1,6-linkage to core N-acetylglucosamine of N-glycans) catalyzed by fucosyltransferase 8 (FUT8) is critical for signaling receptors involved in many physiological and pathological processes such as cell growth, adhesion, and tumor metastasis. Transforming growth factor-β (TGF-β)-induced epithelial–mesenchymal transition (EMT) regulates the invasion and metastasis of breast tumors. However, whether receptor core fucosylation affects TGF-β signaling during breast cancer progression remains largely unknown. Method In this study, gene expression profiling and western blot were used to validate the EMT-associated expression of FUT8. Lentivirus-mediated gain-of-function study, short hairpin RNA (shRNA) or CRISPR/Cas9-mediated loss-of-function studies and pharmacological inhibition of FUT8 were used to elucidate the molecular function of FUT8 during TGF-β-induced EMT in breast carcinoma cells. In addition, lectin blot, luciferase assay, and in vitro ligand binding assay were employed to demonstrate the involvement of FUT8 in the TGF-β1 signaling pathway. The role of FUT8 in breast cancer migration, invasion, and metastasis was confirmed using an in vitro transwell assay and mammary fat pad xenograft in vivo tumor model. Results Gene expression profiling analysis revealed that FUT8 is upregulated in TGF-β-induced EMT; the process was associated with the migratory and invasive abilities of several breast carcinoma cell lines. Gain-of-function and loss-of-function studies demonstrated that FUT8 overexpression stimulated the EMT process, whereas FUT8 knockdown suppressed the invasiveness of highly aggressive breast carcinoma cells. Furthermore, TGF-β receptor complexes might be core fucosylated by FUT8 to facilitate TGF-β binding and enhance downstream signaling. Importantly, FUT8 inhibition suppressed the invasive ability of highly metastatic breast cancer cells and impaired their lung metastasis. Conclusions Our results reveal a positive feedback mechanism of FUT8-mediated receptor core fucosylation that promotes TGF-β signaling and EMT, thus stimulating breast cancer cell invasion and metastasis.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Analysis / Biomedical and Life Sciences / Biomedicine / Breast cancer / Breast carcinoma / Breast Neoplasms - genetics / Breast Neoplasms - pathology / Cancer Research / Carbohydrates / Cell Proliferation - genetics / Core fucosylation / CRISPR / Development and progression / EMT / Epidermal growth factor / Epithelial-Mesenchymal Transition - genetics / Extracellular matrix / Female / Flow cytometry / Fucose / Fucose - genetics / Fucose - metabolism / Fucosyltransferases - genetics / FUT8 / Gene expression / Gene Expression Regulation, Neoplastic - genetics / Genetic aspects / Genomes / Humans / Invasiveness / Laboratories / Lectins / Lentivirus - genetics / Mesenchyme / Metastases / Metastasis / N-Acetylglucosamine / N-glycans / Neoplasm Invasiveness - genetics / Neoplasm Invasiveness - pathology / Neoplasm Metastasis / Oncology / Phosphorylation / Physiological aspects / Polysaccharides / Proteins / Receptors, Transforming Growth Factor beta - genetics / Research Article / Ribonucleic acid / RNA / Signal transduction / Signal Transduction - genetics / Surgical Oncology / TGF-β receptor / Transcription factors / Transforming Growth Factor beta1 - genetics / Transforming growth factor-b / Transforming growth factor-b1 / Transforming growth factors / Tumor cell lines / Tumors / Xenografts