POLYPHENOLS CONTENT AND IN VITRO ANTITUMOUR ACTIVITY OF HYDROALCOHOLIC EXTRACT OF VISCUM ALBUM IN TWO PIGMENTED AND UNPIGMENTED SKIN CANCER CELL LINES

Abstract

Malignant melanoma is the most aggressive type of skin cancer, with an increasing annual incidence. In addition to cutaneous melanoma, another form of melanoma with an increased death rate is uveal melanoma. With both types of melanomas, there is a risk that the malignant cells will become resistant to conventional antitumour therapy. Thus, the present study aimed to evaluate the antitumour effect of a hydroalcoholic extract of Viscum album (VAex) on a pigmented cell line (B164A15) as well as unpigmented (A431). The cytotoxic effect was also followed in the case of a healthy human keratinocyte cell line. The results showed that at low concentrations (< 500 μg/mL), VAex has a selective cytotoxic effect, with healthy cells not being affected. In addition, in the case of tumour cells, VAex exerted a concentration-dependent cytotoxic effect, causing morphological and structural changes in the nucleus, with an apoptotic-like effect. The most affected cells were the unpigmented ones (A431), requiring additional studies to elucidate the mechanism of antitumour action, but also to determine the influence of melanin on the biological action of VAex.