Introduction: Glioblastoma (GBM) is one of the most aggressive and resistant types of brain cancer, which conventional treatments such as surgery, chemotherapy, and radiotherapy have limited effect on its control. In this regard, the use of natural compounds with anticancer properties has been considered as a complementary strategy. The purpose of the current work was to assess the cytotoxicity and pro-apoptotic potential of the plant extracts Echium amoenum and Valeriana officinalis in U87 MG cancer cells. Materials and Methods: Maceration technique was originally utilized in the extraction of the plant extracts. U87MG cells were seeded in 10% fetal bovine serum DMEM media and treated with varying doses (31.25 to 1000 µg/mL) when they attained optimal density. MTT assay was performed to investigate the cytotoxic effect at 24, 48 and 72 hours. To investigate the expression of apoptosis-related genes (Bax, Bcl-2 and Caspase-3), RNA extraction and cDNA synthesis were performed and then the expression of these genes was analyzed by Real-Time PCR. Results and Discussion: The results of MTT assay showed that both extracts inhibited the growth of cancer cells in a dose- and time-dependent manner. Echium amoenum extract at 72 hours and a concentration of 1000 μg/ml showed the highest cell inhibition rate (96%), while Valeriana officinalis extract had 95% inhibition under the same conditions. At the molecular level, Echium amoenum extract significantly increased the expression of Caspase-3 (more than 20-fold) (p<0.0001), while Valeriana officinalis extract did not cause a significant change in the expression of this gene. Also, Bcl-2 expression was significantly increased in the Echium amoenum-treated group (p<0.001), which may indicate a dual cellular response. Conclusion: The results demonstrated that extracts from Valeriana officinalis and Echium amoenum have anticancer effects on GBM cells, maybe by inducing apoptosis. Echium amoenum was more effective in raising Caspase-3 and initiating pathways leading to programmed cell death, whereas Valeriana officinalis primarily worked via controlling the balance of Bax/Bcl-2 proteins. These findings imply that more research should be done on the application of natural substances as a supplemental approach to GBM therapy.
