Abstract:

Objective  To explore whether tumor necrosis factor-α-induced protein-8 like-2 (TIPE2) inhibits toll-like receptor 4 (TLR4) pathway by binding to caspase-8 to participate in the progression of colon cancer. Methods  TIPE2 expression was down-regulated in HT-29 cells by small RNA interference technology. TLR4 pathway was activated with 1μg/mL lipopolysaccharide (LPS). Caspase-8 activities were detected in the TIPE2 knockdown cells, TIPE2 knockdown & TLR4 activation cells, TLR4 activation cells and wild-type cells. Results  Real-time PCR found that TIPE2-siRNA decreased the TIPE2 expression successfully. Caspase-8 activities were higher in TIPE2 knockdown cells and TLR4 activation cells than in wild-type cells (P<0.05). Caspase-8 activities were higher in TIPE2 knockdown & TLR4 activation cells than in TLR4 activation cells (P<0.05). Conclusion  TIPE2 can inhibit caspase-8 activity and it is involved in the progression of colon cancer through its binding to caspase-8 which negatively regulates TLR4 pathway.

Key words: Toll-like receptor 4, Colon tumorogenesis, Colon inflammation, Tumor necrosis factor- α-induced protein-8, Caspase-8