Chloroform leaf extract of Daphne gnidium inhibits growth of melanoma cells and enhances melanogenesis of B16-F0 melanoma

• Extracts from D. gnidium inhibited growth of melanoma B16-F0 and B16-F10 cells.
• Chloroform extract from D. gnidium induces cell cycle arrest of B16 melanoma cells.
• Chloroform extract induces melanin production by B16-F0 melanoma cells.
• Chloroform extract induces tyrosinase activity in B16-F0 melanoma cells.

The antiproliferative potential of chloroform, methanol and butanol extracts from Daphne gnidium leaves on B16-F0 and B16F-10 melanoma cells was assessed. Cell viability was determined using the MTT assay, and flow cytometry was used to analyse effects of extract on progression through the cell cycle and apoptosis. In addition, amounts of melanin and tyrosinase activity were measured spectrophotometrically at 475 nm. Chloroform extract exhibited significant anti-proliferative activity after incubation with the two types of tumour skin cells. Increase of tyrosinase activity, and of melanin synthesis which are markers of differentiation of malignant melanoma cells, were observed with the chloroform extract. Furthermore, cell cycle analysis revealed that B16-F0 and B16-F10 cells treated with chloroform extract were arrested predominantly in S phase.