Immune Cell-Conditioned Media Suppress Prostate Cancer PC-3 Cell Growth Correlating with Decreased Proinflammatory/Anti-inflammatory Cytokine Ratios in the Media Using 5 Selected Crude Polysaccharides

Abstract

Five different crude polysaccharides from guava seed (GSPS), bitter buckwheat (BBPS), common buckwheat (CBPS), red Formosa lambsquarters (RFLPS), and yellow Formosa lambsquarters (YFLPS) were isolated to treat human prostate cancer PC-3 cells via direct action or tumor immunotherapy. The splenocyte- and macrophage-conditioned media (SCM and MCM) were prepared using individual selected polysaccharides, and then SCM or MCM was further collected to treat PC-3 cells. The relationship between PC-3 cell growth and Th1/Th2 cytokines in SCM as well as proinflammatory/anti-inflammatory cytokine secretion profiles in MCM were delineated. The results showed that all 5 selected polysaccharides did not significantly inhibit PC-3 cell growth via direct action. However, SCM or MCM cultured in the absence or presence of 5 selected polysaccharides significantly (P