The cytolytic effect of a glycoconjugate extracted from corms of saffron plant (Crocus sativus) on human cell lines in culture

Corms of Crocus sativus L. (Iridaceae) contain a glycoconjugate that shows cytotoxic activity on tumoral cells in culture. Studies of intracellular calcium fluctuations, and release of lactate dehydrogenase in human cervical epitheloid carcinoma cells, showed that this compound caused plasma membrane damage, allowing movements of both calcium and macromolecules, and leading to cell lysis. Analysis of DNA fragmentation showed that cell death was not mediated by apoptosis. This molecule is active against human tumoral cells derived from fibrosarcoma, cervical epithelioid carcinoma and breast carcinoma, with IC50 values of 7, 9 and 22 mu g/ml, respectively. The proteoglycan is about 8 times more cytotoxic for malignant cells than for their normal counterparts. In addition, 100 mu g/ml of proteoglycan produced 50% in vitro lysis of normal human erythrocytes, whereas 320 mu g/ml induced about 60 % cell death on cultured human hair follicles. Altogether, these results suggests a distinctive cytotoxic activity of this molecule on different human cell types.