Investigation of the potential anticancer effects of napelline and talatisamine dirterpenes on experimental brain tumor models.

Brain cancers are one of the most aggressive tumours in humans. Especially, gliomas are among the deadliest of human cancers and show high resistance to chemotherapeutic agents. On the other hand, discovery of biologically effective non-synthetic biomaterials in treatments of different diseases, especially cancer, has continued to be one of the most popular research topics today. Therefore, we aimed to investigate biochemical, cytological and molecular genetic effects of napelline and talatisamine diterpenes in human U-87 MG glioma cells by using total antioxidant status and total oxidative status, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxphenyl)-2-(4-sulfophenyl)-2H-tetrozolium, inner salt and lactate dehydrogenase release assay and RT2 Prolifer PCR Arrays. Our results revealed that napelline and talatisamine exhibited cytotoxic effects at high doses. Napelline and talatisamine diterpenes increased apoptosis compared to control in U-87 MG cells. While napelline induced up-regulation of 50 and down-regulation of 13 genes, talatisamine induced up-regulation of 32 and down-regulation of 18 genes in U-87 MG cells. Napelline was shown to have a higher anticancer activity than talatisamine. We think that, napelline and talatisamine might be evaluated as potential chemotherapeutic agents for treatment of glioblastoma.