Evaluation of Silibinin Effects on P21,P27 and Some Specific Apoptotic Genes in MDA-MB-231 Breast CancerCell Line

Breast cancer is the most common cause of death in women and the fourth leading cause ofcancer in developed countries (MDCs) and least developed (LDCs) worldwide. Silibinin isextracts from the medicinal plant Silybum marianum (milk thistle) and have significant antineoplasticeffects in a variety of in vitro and in vivo cancer models including breast cancer. Inthis study, the effect silibinin on cell viability, apoptosis, and p21, p27 and Bcl2 genesexpression in breast cancer MDA-MB-231 cell line was evaluated. Human breast cancersMDA-MB-231 cells were routinely maintained in RPMI 1640, supplemented with 10% FBSand antibiotics at 37 °C in a humidified atmosphere containing 5% CO2. MDA-MB-231breast cancer cells were treated with or without silibinin in vitro for 48h. Cell proliferation wasmeasured by MTT assay. Cell apoptosis was observed by light microscopy and flowcytometry with Annexin-V/PI. The changes in p21, p27 and Bcl2 gene expression wasdetermined by RT Q PCR. Silibinin significantly decreased the proliferation of MDA-MB-231cells in a dose and time-dependent manner (p<0.05). Apoptosis evaluation by flow-cytometrymethod showed silibinin significantly increases induction both early and late apoptosis in MDAMB-231 breast cancer cell line (P<0.05). ). Also silibinin significantly UPregulated the P21, p27 as 4.15, 4.1 –fold change respectively and down regulate the Bcl2 gene expression as 0.335 –fold change (p <0.05). silibinin showed strong inhibitory effect on MDA-MB-231 breastcancer cells proliferation and induction of apoptosis.

Keywords:

P21 , P27 , Bcl2 , MDA-MB-231 Breast Carcinoma , Silibinin