Abstract

APOPTOTIC EFFECT OF GOLD NANOPARTICLES ON HUMAN COLON CANCER CELL LINES CACO-2 BUT NOT ON THE NORMAL EPITHELIAL CELL LINES WISH

Marwa Alkayaty, Nahla.G.Mohamed, Rehab. E. El-Hennamy and Soad Nady*

Abstract

Colorectal cancer (CRC) is the third most common cancer worldwide. Consequently, the discovery of new strategies for therapeutic intervention remains a priority. The gold nanoparticles (AuNPs) have been discovered to exert cytotoxicity and induce apoptosis in some cancer cells. The aim of the present study was to investigate the effect of AuNPs on human colon cancer cell lines (Caco-2) and normal human epithelial cell lines (WISH) in vitro. The two cell lines were treated with different concentrations of AuNPs for 5 days and cytotoxicity of AuNPs was assessed. RT-PCR was used to analyze the expression profiles of pro- and anti-apoptotic genes. Tumor necrosis factor alpha (TNF-α) and interlukin-6 (IL-6) levels were measured in the culture supernatant using ELISA. Results revealed that AuNPs has a cytotoxic effect on Caco-2 cell lines at high and low concentrations, but has no cytotoxic effect on WISH cell lines. Upregulation of the pro-apoptotic gene (bax) was induced in AuNPs treated Caco-2 cell lines but not WISH cells. The levels of IL-6 secreted by Caco-2 cell line treated with AuNPs increased gradually up to 96 h then began to decline thereafter. On the other hand, the levels of TNF-α reached its peak after 24h then started to decrease gradually. In conclusion, AuNPs did not cause acute cytotoxicity for normal human epithelial cell lines (WISH), but they have the ability to induce apoptosis in human colon cancer cell lines (Caco-2).

Keywords: Colon cancer, Gold nanoparticles, Apoptosis, TNF-?, Interlukin-6.