Structural characterization of two isolectins from the marine red alga Solieria filiformis (Kützing) P.W. Gabrielson and their anticancer effect on MCF-7 breast cancer cells

• Published in: International journal of biological macromolecules Vol. 107; no. Pt A; pp. 1320 - 1329
• Main Authors: Chaves, Renata Pinheiro, Silva, Suzete Roberta da, Nascimento Neto, Luiz Gonzaga, Carneiro, Romulo Farias, Silva, André Luis Coelho da, Sampaio, Alexandre Holanda, Sousa, Bruno Lopes de, Cabral, Maria Guadalupe, Videira, Paula Alexandra, Teixeira, Edson Holanda, Nagano, Celso Shiniti
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-02-2018
• Subjects: Anticancer effect; Apoptosis - drug effects; Breast Neoplasms - drug therapy; Cell Proliferation - drug effects; Female; Humans; Lectin; Lectins - administration & dosage; Lectins - chemistry; Marine alga; MCF-7 Cells; Rhodophyta - chemistry; Lectin; Marine alga; Anticancer effect
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2017.09.116

As described in the literature, Solieria filiformis lectin (SfL) from the marine red alga S. filiformis was found to have antinociceptive and anti-inflammatory effects. In this study, we characterized two SfL variants, SfL-1 and SfL-2, with molecular mass of 27,552Da and 27,985Da, respectively. The primary structures of SfL-1 and SfL-2 consist of four tandem-repeat protein domains with 67 amino acids each. SfL-1 and -2 showed high similarity to OAAH-family lectins. 3D structure prediction revealed that SfL-1 and -2 are composed of two β-barrel-like domains formed by five antiparallel β-strands, which are connected by a short peptide linker. Furthermore, the mixture of isoforms (SfLs) showed anticancer effect against MCF-7 cells. Specifically, SfLs inhibited 50% of viability in MCF-7 cells after treatment at 125μg.mL−1, while the inhibition of Human Dermal Fibroblasts (HDF) was 34% with the same treatment. Finally, 24h after treatment, 25% of MCF-7 cells were in early apoptosis and 35% in late apoptosis. Evaluation of pro- and anti-apoptotic gene expression of MCF-7 cells revealed that SfLs induced caspase-dependent apoptosis within 24h.