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Breast cancer known for its high metastatic potential is responsible for large mortality rate amongst women; hence it is imperative to search for effective anti-metastatic molecules despite anticancer drugs. The current study describes the potential of Remusatia vivipara lectin (RVL), inducing apoptosis in breast cancer cells there by limiting motility and invasiveness. RVL binds to the cell surface glycans of MDA-MB-468 and MCF-7 cells, exhibiting strong glycan mediated cytotoxic effect, but show marginal effect on non-tumorigenic MCF-10A cells. RVL elicits increased cellular stress, apoptotic vacuoles and nuclear disintegration in both MDA-MB-468 and MCF-7 cells accompanied by depletion of G0/G1, S and G2/M phases. Lectin interaction induced production of reactive oxygen species through altering mitochondrial membrane potential progressing to apoptosis. Further, RVL strongly elicited reproductive cell death in MDA-MB-468 cells and showed strong inhibitory effect on neovascularization demonstrated in chorioallantoic membrane assay. Treatment of MDA-MB-468 cells with RVL, suppress the motility and invasive property as shown by scratch wound heal and Boyden chamber transwell assays respectively. These results provide an insight into significance of interaction of RVL with specific cell surface high mannose N-glycans resulting in curtailing the metastatic ability of cancer cells. [ABSTRACT FROM AUTHOR]

Abstract: The insect pest Spodoptera litura is considered a major threat to many economically important food and commercial crops. The present study establishes the toxic effects of Sclerotium rolfsii lectin (SRL) against S. litura larvae fed an artificial diet containing the purified lectin. The toxicity of SRL, as determined by feeding assays using different concentrations of the lectin, showed marginal effects on larval growth but a remarkable mortality rate of 68.52 ± 8.48% at the highest lectin concentration, 0.06% (600 μg/g), with an LC50 value of 430 μg/g of artificial diet. SRL is resistant to proteolysis by larval gut proteases even after 24-h incubation. Histochemical studies and western blot analyses of lectin binding revealed the interaction of the lectin with specific membrane glycoproteins on epithelial cells of the midgut. Identification of SRL-interacting midgut membrane proteins using lectin affinity chromatography and ESI-Q-TOF analysis revealed the involvement of these proteins in immunomodulatory responses in insects. Active caspase-3-like activity and DNA fragmentation observed in the midgut epithelial cells of larvae fed a lectin-containing diet supported the mechanism of apoptosis-induced death. These findings suggested that SRL can be a valuable tool in plant biotechnology for developing insect-resistant transgenic crops. [Copyright &y& Elsevier]