Suppression of pulmonary tumor promotion and induction of apoptosis by Crocus sativus L. extraction.

Crocus sativus L., commonly known as saffron, is the raw material for one of the most expensive spice in the world, and it has been used in folk medicine for centuries. We investigated the potential of the ethanolic extract of saffron to induce cytotoxic and apoptosis effects in carcinomic human alveolar basal epithelial cells (A549), a commonly used cell culture system for in vitro studies on lung cancer. The cells were cultured in Dulbecco's modified Eagle's medium with 10% fetal bovine serum treated with different concentrations of the ethanolic extract of saffron for two consecutive days. Cell viability was quantitated by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay. Apoptotic cells were determined using annexin V-fluorescein isothiocyanate by flow cytometry. Saffron could decrease the cell viability in the malignant cells as a concentration- and time-dependent manner. The IC₅₀ values against the A549 cell lines were determined as 1,200 and 650 μg/ml after 24 and 48 h, respectively. Saffron-induced apoptosis of the A549 cells in a concentration-dependent manner, as determined by flow cytometry histogram of treated cells that induced apoptotic cell death, is involved in the toxicity of saffron. It might be concluded that saffron could cause cell death in the A549 cells, in which apoptosis plays an important role. Saffron could also be considered as a promising chemotherapeutic agent in lung cancer treatment in future.