Abstract

Arabinoxylans
(AXs) are hemicelluloses composed of xylose and arabinose residues. They are
found in a variety of agricultural products. AXs can stimulate innate and
adaptive immune systems by enhancing macrophage phagocytosis and natural killer
cell activities. Modified AXs increase the susceptibility of cancer cells to
various cytotoxic drugs. Colon cancer is one of the most common malignancies
worldwide. It causes millions of deaths annually. The aims of this study
were to evaluate the AXs on the viability of colon cancer cells, and identify
their immunomodulatory effects in vitro. 

Results show
that AXs alone had no effects on the viabilities of HT-29 cells. However,
there were synergistic effects on reducing cell viabilities when AXs
combined hydroxyurea. HT-29 cells treated with AXs had up-regulated
expressions of IL-8, TNF-α, TLR4, and
down-regulated CLEC7A, MCP-1 comparing untreated
cells. However, when HT-29 cells were pre-treated with LPS, AXs showed
anti-inflammatory effects via inhibiting IL-8
and TLR4, but stimulating IL-10 expressions. 

It indicates that the
contrasting immunomodulatory effects of AXs are associated with the status of
cancer cells. AXs have potential applications in adjuvant therapy for colon
cancer. Further studies are required, especially using in vivo models to
exploit fully the potential of the immunomodulatory effect of arabinoxylans on
colon cancer.