Contrary to known silibinin is not an anticancer agent and liver protective supplement

Abstract

Silibinin is a flavinoid that is the main component of the milk thistle plant and is widely used around the world, thought to have liver protective and anticancer effects. In this study, contrary to what is generally known, it was aimed to show that silibinin is neither a healthy liver protective supplement nor an anticancer agent for hepatocellular cancer cells. For this purpose, molecular effects of silibinin were investigated in both HepG2 (hepatocellular cancer) and AML-12 (healthy liver) cells. The cytotoxic concentrations of silibinin investigated by MTT analysis. Cell proliferation by wound healing assays, intracellular apoptosis and cell division events demonstrated by fluorescent microscopy imaging via Annexin V/ PI and Hoechst 34580 staining. Gene expression level changes were investigated by real-time polymerase chain reaction. In the study, IC50 values were calculated as 739.9 mM for AML-12 and 1.35 M for HepG2 in 24 h, 529.23 ?M for AML-12 and 15.51 mM for HepG2 in 48-h of silibinin administration. From these data, IC50 value of 48 h of silibinin administration for the AML-12 cell line resulted a decrease in AML-12 cell quantity, whereas an increase in HepG2 cells. Fluorescent staining studies show that, there was an intense proliferation in the HepG2 cells, whereas an important apoptotic effect induced in the AML-12 cell line as a result to 529.23 ?M silibinin application. Also, all proliferation and oncogene expression levels were incrased in HepG2 cells, but expression levels of Akt, ErbB2 were decreased in AML-12 cells, whereas APEX1 DNA repair, CuZn-SOD oxidative stress gene expression levels were increased. As a result, application of 529.23 ?M silibinin was found to be cytotoxic for AML-12 cells as well as proliferative effect on HepG2.