Proteome Changes in Caco-2 Cells Treated with Monascus-Fermented Red Mold Rice Extract

Monascus-fermented red mold rice has been extensively used as a folk medicine for thousands of years. Monascus secondary metabolites, including monacolin K, monascorubrin, and ankaflavin, have been reported to have an antiproliferative effect on cancer cells. However, the cell machinery responsible for the antiproliferation of Monascus-fermented red mold rice treatment in cancer cells remains unclear. A proteomic approach using two-dimensional gel electrophoresis, matrix-assisted laser desorption ionization time-of-flight/time-of-flight mass spectrometry, and tandem mass spectrometry was used to identify proteins with modified expression in Caco-2 cells treated with Monascus-fermented red mold rice extract. A total of 20 proteins were identified with significantly altered expression (P < 0.05) in response to Monascus-fermented red mold rice extract treatment. The deregulated proteins that were identified included heat shock protein 70, protein kinase C epsilon type, clusterin-associated protein 1, and two tumor suppressors (N-chimaerin and calponin-2). Our results suggested the involvement of heat shock protein 70-mediated cytotoxicity in the Caco-2 cells treated with Monascus-fermented red mold rice extract.