Candelariella vitellina extract triggers in vitro and in vivo cell death through induction of apoptosis: A novel anticancer agent

Abstract

Candelariella vitellina is common green-yellow lichen found on barks, wood, and rocks in Japanese forests. To investigate the mechanism of its anticancer potential, C. vitellina (80% MeOH/H₂O) extract was prepared. High-performance liquid chromatography-high-resolution electrospray ionization mass spectrometry analysis revealed seven new compounds and 11 natural compounds of terpenes and polyketides. In vitro cytotoxicity analysis of Caco-2 cells exhibited an IC₅₀ of 125 ± 4.1 μg/mL. No significant cytotoxicity was observed in vitro in normal human peripheral lymphocytes. Both the IC₂₅ and IC₅₀ were determined to explore the potent anticancer potential in this study. C. vitellina exhibited a mitochondrial P53-independent apoptotic effect with negative P53 expression and an elevated BAX/BCL2 ratio as well as upregulated CASP3 mRNA expression. Similarly, in vivo analysis showed the same pattern of anticancer potential but was dependent on the P53 expression. Furthermore, C. vitellina induced antioxidative conditions in vitro and in vivo. The decreased invasion of tumor cells in vivo and increased apoptotic features in vitro and in vivo suggest the moderate to strong apoptotic anticancer potential of C. vitellina. However, further studies are needed to determine the extent and mechanism of action on different cell lines to support the anticancer properties of this lichen.

Keywords: Anticancer; Apoptosis; Candelariella vitellina; Polyketides; Terpenes.