Peganum harmala L.’s anti-growth effect on a breast cancer cell line

• The expression of two genes TRAIL, death receptor, and Caspase-8, associated with extrinsic pathway, up-regulated upon treating with P. harmala L.’s seed extract suggesting that the extract induces mainly on apoptosis extrinsic pathway.
• The pro-apoptotic genes, BH3 multidomain, Bax (Bcl-2-associated X protein) and Bak (Bcl-2 homologous antagonist/killer) caused permeability in mitochondrial membrane which was inhibited by anti-apoptotic proteins, Bcl-2, Bcl-xl.
• As a consequence of binding BH3-only proteins (BID, BIM (Bcl-2-like protein 11), BAD (Bcl-2-associated death promoter), and PUMA to anti-apoptotic proteins, their activities were inhibited.
• Both p53 and p21 were up-regulated in treated cells with P. harmala’s seed extract, hence p53 as transcription regulator up-regulated Bax, Puma and TRAIL.
• As long as the expression of anti-apoptosis Bcl-2 gen reduced dramatically, an over-expression in apoptosis genes, Bax and Puma, was monitored indicating activation of intrinsic apoptosis pathway.
• The results confirm the positive effect of P. harmala L.’s extract in inducing apoptosis in MDA-MB-231 cell line in both intrinsic/extrinsic apoptosis pathways and also in blocking cell cycle life.

This research was done to evaluate the induction of apoptosis in MDA-MB-231 breast cancer cell line by Peganum harmala’s extract, in which a significant amount of ß-carbolines is included. The apoptosis incidence was assessed through Annexin-V-Flous kit. The expressions of genes through which intrinsic apoptosis pathway are involved, Bax, Bcl-2, Bid, and Puma, over the genes the expressions of which are linked to extrinsic apoptosis pathway, TRAIL, Caspase8, p21, and p53, were examined by RT-PCR and Real-time PCR. The results demonstrate that the extract decreases the growth rate of the cancer cell line through inducing apoptosis mechanism. As long as the expression of anti-apoptosis Bcl-2 gen reduced dramatically, an over-expression in Bax and Puma genes was monitored indicating activation of intrinsic apoptosis pathway. A notable over-expression observed with TRAIL and Caspase8 genes as well as Bid gene. The latter is an intermediate for both intrinsic and extrinsic pathways of apoptosis.