Journal of Biology and Nature

Protein sialylation has been demonstrated to play a role in tumour progression and metastasis. Elevated levels of sialic acid have been shown to interfere with receptor-ligand interactions, thereby providing a protective barrier for tumour cells against the immune system. Galectin 3 is a protein that binds to β-galactosides, and its increased expression is required for proliferation, angiogenesis and the inhibition of apoptosis in cancer cells. TNF-α is one of the essential pro-inflammatory cytokines found in he tumor microenvironment of breast cancer patients, affecting tumor cell proliferation and survival. In this study, the expression levels of sialic acid α2-3, α2-6 and Galectin 3 in MCF-7 cells stimulated with TNF-α were determined using flow cytometry and fluorescence microscopy. The percentage of cells expressing α2, 3 sialic acid recognised by the Maackia amurensis lectin increases at four hours. In the case of α2, six sialic acid recognized by the Sambucus nigra lectin, exhibited a higher intensity at 6 hours. Furthermore, the expression of both α-2,3 and α-2,6 sialic acid was observed on the cell surface. The results obtained for Galectin 3 demonstrated a decrease in expression relative to unstimulated cells. Galectin-3 expression was predominantly observed in the nucleus and cytoplasm. These results suggest that alterations in the expression of sialic α2,3 and α2,6 and galectin-3 may promote tumor cell migration; however, further research is required to validate this hypothesis.