Background The biodiversity of the marine environment and the associated chemical diversity constitute a practically unlimited source of new active substances in the field of the development of bioactive products. manner. This inhibition is usually reliant on its ability to interact with integrins. Findings To conclude, we have exhibited for the first time that venom and its fractions especially (F1 and F2) display potent anti-tumoral properties. Separation by sephadex G-75 chromatography give rise to more active fractions than the crude venom draw out. The purification and the determination of chemical structures of compounds of these active fractions are under investigation. Overall, venom may has the potential to serve as a template for future anticancer-drug development. (venom and their mechanism of action on malignancy cells remains unknown. Thus, this study attempts, for the first ESR1 time to characterize and evaluate the exact role of venom and its semi-purified fractions on (i) viability of human glioblastoma cells (U87), (ii) cell proliferation and (iii) cell adhesion to immobilized extracellular matrix (ECM) protein (fibrinogen). Materials and methods Chemicals 3C4, 5-dimethylthiazol-2-yl, 2,5-diphenyltetrazolium bromide (MTT), Cell culture medium (RPMI1640), foetal calf serum (FCS), phosphate buffer saline (PBS), trypsinCEDTA, penicillin and streptomycin combination and l-glutamine (200?mM) were from GIBCO-BCL (UK). Poly-L-lysine, Human fibrinogen was purchased from Sigma (St Quentin Fallavier, France). All other chemicals used were of analytical grade. Preparation of nematocysts Specimens of were collected from the bay of Monastir, Tunisia, in May 2011, and recognized by professor Mohamed Nejib Daly Yahia from Faculty of Sciences of Bizerte, (Bizerte, Tunisia). Tentacles were excised manually from living specimens immediately after capture. The nematocysts isolation method has been previously explained by Arillo et al.  with a slight changes. Tentacles were submerged in distilled water for 5?h at 4C. The ratio of organic tissue to distilled water was approximately 1:5 (v/v). After a total detachment of the skin, the tissue was removed from the suspension made up of both skin and undischarged nematocysts deriving from the osmotic rupture of nematocysts. The nematocysts, attached to the epidermal tissue, were separated by stirring. The nematocysts suspension was repeatedly washed in distilled water and filtered through plankton MP-470 nets to remove most of the tissue debris, and then centrifuged at 4C (ALC PK 120R, 4000?g for 5?min). The content, purity and MP-470 honesty of nematocysts (cnidocysts) were controlled microscopically . Nematocysts lysis and protein extraction Crude venom was extracted by sonication on ice (Sonoplus, 70?mHz, 30 occasions, 20?s) MP-470 of nematocysts as described by Marino et al. . After sonication, the suspension was centrifuged at 15,000?rpm for 15?min at 4C. The supernatant was cautiously removed, filtered and lyophilized. Protein determination The protein content of venom was decided according to the Bradford method (BioRad Labs, Hercules, CA) . venom and fractions concentrations send to protein concentration expressed in models of g ml-1. Size exclusion chromatography About 300?mg of crude venom of was dissolved in filteredCdegassed double-distilled water. After centrifugation at 17 000?g for 15?min at 4C, the supernatant was loaded on Sephadex G-75 gel-filtration chromatography columns (2.6??100?cm; Pharmacia), previously equilibrated with 200?mM ammonium acetate, pH 6.8 and eluted under the same conditions. The circulation rate was 3?ml/min using a Bio-Rad 2110 portion collector and the elution of the proteins was monitored at 280?nm by an ultraviolet detector. Cell viability assay Cytotoxicity of crude venom and its fractions was defined using the colorimetric method explained by Mossmann, . The MTT test assesses cell metabolism based on the ability of the mitochondrial succinate-dehydrogenase to convert the yellow compound MTT to a blue formazan dye. The amount of dye produced is usually MP-470 proportional to the number of live metabolically active cells. Cells were seeded on 96-well culture dishes (Polylabo, France) at 105 cells/ well and treated with increasing concentrations of crude venom draw out at 37C. After 24?h, the culture medium was replaced by 200?t medium containing 0.5?mg/ml MTT and the dishes were incubated 3?hours at 37C. The medium was then removed and replaced by 200?l of (0,04?M HCl/isopropanol) to solubilize the converted crimson dye in culture.