Inhibition of fucosylation in breast cancer reduces E-selectin ligand expression, cell proliferation and ERK1/2 and p38 MAPK activation

Breast cancer is the most common type of cancer in women and their second leading cause of death among cancer. Fucosylated glycans are overeexpressed in breast cancer, such as sialyl-Lewis X/A (sLe^X/A), and their expression is related to increased disease progression and metastasis. These glycans in tumor circulating cells mediate binding to vascular E-selectin, initiating tumor extravasation. However, their role(s) in breast carcinogenesis is still unknown. In this study, the research group leaded by professor Paula Videira assessed the contribution of the fucosylated glycans sLe^X/A in cancer cell adhesion to E-selectin, and the effects of fucosylation in cell signaling and proliferation in breast cancer. The data showed that the treatment with 2-fluorofucose, a fucosylation inhibitor, suppressed the adhesion of a breast cancer cell line to E-selectin as well as reduced their migration and proliferation rate, decreasing drastically the expression of cytokine growth factors and the activation of signaling pathways ERK1/2 and p38 MAPK. These findings provide mechanistic insights on the role of fucosylation in breast carcinogenesis, suggest that inhibition of synthesis of fucosylated glycans might be beneficial in preventing tumor cell progression and metastasis. 

Authors and Affiliations:

Carrascal MA^1,2, Silva M^2,3, Ramalho JS², Pen C⁴, Martins M⁴, Pascoal C¹, Amaral C¹, Serrano I⁵, Oliveira MJ^6,7 Sackstein R³, Paula A Videira^1,2,8

¹ UCIBIO, Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Portugal

² CEDOC, Chronic Diseases Research Center, NOVA Medical School / Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisbon, Portugal

³ Departments of Dermatology and Medicine, Brigham & Women’s Hospital, and Program of Excellence in Glycosciences, Harvard Medical School, USA

⁴ Centro Hospitalar de Lisboa Central, EPE - Serviço de Anatomia Patológica, Lisbon, Portugal;

⁵ Hospital de Cascais, Cascais, Portugal

⁶ New Therapies Group, INEB-Institute for Biomedical Engineering, Porto, Portugal

⁷ Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal

⁸ CDG & Allies – PPAIN Congenital Disorders of Glycosylation Professionals and Patient Associations International Network

Abstract:

Breast cancer tissue overexpresses fucosylated glycans, such as sialyl-Lewis X/A (sLe^X/A), and α-1,3/4-fucosyltransferases in relation to increased disease progression and metastasis. These glycans in tumor circulating cells mediate binding to vascular E-selectin, initiating tumor extravasation. However, their role(s) in breast carcinogenesis is still unknown. Here, we aimed to define the contribution of the fucosylated structures, including sLe^X/A, to cell adhesion, cell signaling and proliferation in invasive ductal carcinomas (IDC), the most frequent type of breast cancer. We first analyzed expression of E-selectin ligands in IDC tissue, and established primary cell cultures from the tissue.  We observed strong reactivity with E-selectin and anti-sLe^X/A antibodies in both IDC tissue and cell lines, and expression of α-1,3/4 fucosyltransferases FUT4, FUT5, FUT6, FUT10 and FUT11. To further assess the role of fucosylation in IDC biology, we immortalized a primary IDC cell line with hTERT to create the “CF1_T cell line”.  Treatment with 2-fluorofucose (2-FF), a fucosylation inhibitor, completely abrogated its sLe^X/A expression and dramatically reduced adherence of CF1_T cells to E-selectin under hemodynamic flow conditions. In addition, 2-FF treated CF1_T cells showed a reduced migratory ability, as well as decreased cell proliferation rate. Notably, 2-FF treatment lowered the growth factor expression of CF1_T cells, prominently for FGF2, VEGF-A and TGF-β, and negatively affected activation of ERK1/2 and p38 MAPK signaling pathways. These data indicate that fucosylation licenses several malignant features of IDC, such as cell adhesion, migration, proliferation and growth factor expression, contributing to tumor progression. 

Journal: Molecular Oncology

Link: http://onlinelibrary.wiley.com/doi/10.1002/1878-0261.12163/abstract