PDTC antagonized polysaccharide-induced apoptosis in MCF-7 cells through a caspase-8 mediated Fas pathway

• Cartilage polysaccharide (PS) induced apoptosis in MCF-7 breast cancer cells.
• Caspase-8 mediated Fas signaling pathway was involved in PS-induced apoptosis.
• Fas was expressed in nucleus cell membrane firstly and then on outside membrane.
• NF-κB inhibitor PDTC may act as a PS antagonist to reduce the apoptosis rate.

Cartilage polysaccharide (PS) was extracted from porcine cartilage to investigate its anti-tumor effect. In this study, we showed that PS induced apoptosis in MCF-7 breast cancer cells by activating the caspase-8 mediated Fas signaling pathway. The PS inhibited MCF-7 cell proliferation in a dose-dependent and time-dependent manner, and had no toxic effect on normal cells such as NIH-3T3 cells. An increase of Fas protein expression was first located on the nuclear membrane and then on the outside membrane. Cleaved caspase-8 was activated after PS treatment. NF-κB activation was not involved in the PS induced apoptosis, but the NF-κB inhibitor PDTC may act as a PS antagonist to reduce the apoptosis rate and Fas protein expression in PS-induced apoptosis in MCF-7 cells.