Effects of spider Macrothele raven venom on cell proliferation and cytotoxicity in HeLa cells

Aim:To examine the effect of venom from the spider Macrothele raven on cellproliferation and cytotoxicity in human cervical carcinoma,HeLa cells.Methods:Morphological and biochemical signs of apoptosis appeared using acridine or-ange-ethidium bromide (AO/EB) staining.Marked morphological changes in HeLacells alter treatment with spider venom were observed using scanning electronmicroscopy (SEM) and transmission electron microscopy (TEM).Cell prolifera-tion and cytotoxicity were determined by [methyl-~3H] thymidine assay ([~3H]TdR)and lactate dehydrogenase (LDH) release,respectively.DNA fragmentation andcell cycle distribution were monitored using flow cytometry.In addition,Westernblot analysis was used to evaluate the level of caspase-3 expression.In vivoexamination of the inhibition of the size of tumors in nude mice treated with spidervenom was measured.Results:Marked morphological changes were observedusing AO/EB staining,SEM and TEM assay.Spider venom at concentrations of10-40 mg/L caused dose- and time-dependent inhibition of HeLa cell proliferation.The ratio of apoptosis and necrosis increased.The activity of caspase-3 wasupregulated after spider venom treatment.In vivo study of tumor size revealedthat tumors significantly decreased in size from controls to tumors treated for 3weeks with spider venom (P<0.05).Conclusion:The inhibition of HeLa cells bythe venom of the spider Macrothele raveni was carried out in three ways:induc-tion of apoptosis,necrosis of toxicity damage and direct lysis.Spider venom is anovel anti-tumor material both in vitro and in vivo.