Abstract
Glioblastoma presents one of the most formidable challenges in cancer treatment, remaining persistently incurable. There is a pressing need to explore less toxic alternatives, particularly natural remedies that could be applied in glioblastoma therapy. The aim of this research is to investigate the antiproliferative potential of selected stone fruit juices—tart cherry (Prunus cerasus), cornelian cherry (Cornus mas), and blackthorn (Prunus spinosa)—on U87-MG and GBM43 glioblastoma cells. Their effects were compared with temozolomide (TMZ), the current standard treatment. Additionally, the juices were assessed for their bioactive compounds and antioxidant potential. Unlike the other two juices, blackthorn juice did not exhibit an antiproliferative effect on U87-MG cells. However, all three juices, including blackthorn, demonstrated antiproliferative potential against TMZ-resistant GBM43 cells. Cornelian cherry exhibited an even stronger inhibitory effect than TMZ. This observation correlated with cornelian cherry being rich in iridoids, while tart cherry juice contained significant amounts of anthocyanins and proanthocyanidins. This research sheds light on the potential of cornelian cherry juice as a source of bioactive compounds with antiproliferative effects against glioblastoma cells, particularly TMZ-resistant GBM43 cells. Further research is warranted to explore the potential development of these compounds into therapeutic agents, either as single entities or in combination therapies for glioblastoma treatment.