The effect of Citrullus colocynthis on the induction of Casp3 and Casp8 gene expression on human Glioblastoma U87 cell line

Using in vitro MTT assay and Real-time PCR, the cytotoxicity and cell inhibition mechanism of using Citrullus colocynthis on human glioblastoma U87 cell line was investigated.

The plant extract was extracted using ethanol (70%). To investigate the cytotoxic effects of Citrullus colocynthis extract on U87 cell line, 10 4 cells per well was incubated with different concentration of the prepared plant extract in groups for different concentrations during 24, 48, and 72 hours and the impact was measured using MTT assay. 24 hours IC50 was used for gene expression that was investigated using Real-time PCR.

From analytical data results, it was determined that at the concentrations higher than 1000 µg/ml, the plant extract can inhibit the cell growth completely and calculated IC50 for 24,48, and 72 hours incubation is 1337.42 (p≤0.0001), 892.99 (p=0.0012), and 387.49 (p=0.0001) µg/ml respectively. Casp3 and Casp8 gene expression in U87 cells, treated with IC50 concentration of plant extract for 24 hours, was 3.052-fold (P=0.0265) and 2.099-fold (P=0.0013) more than normal media incubated U87 cells, respectively.

The data revealed from this work determined that Citrullus colocynthis extract has concentration and time dependent toxicity effects on U87 cell line and the inhibition mechanism of this plant may be due to the induced Casp3 and Casp8 gene expression which leads to extrinsic apoptosis pathway. So, Citrullus colocynthis extract can be used to inhibit glioblastoma cells growth and may treat brain tumor.