Abstract: The effect of casein glycomacropeptide (CGMP) on the nuclear transcription factor (NF)-κB signaling pathway in colorectal carcinoma cells was assessed in order to provide a theoretical basis for its anti-inflammatory activity. As an extension of our previous work investigating the influence of CGMP on the expression of COX-2, iNOS and GST-π in colon cancer HT-29 cells, this study determined whether the NF-κB signaling pathway in LPS challenged HT-29 cells was activated through observing p65 nuclear translocation by immunofluorescence microscopy. The challenged cells were treated with CGMP and the expression levels of inflammatory cytokines and angiogenesis factors in the cell cultures were detected by enzyme-linked immunosorbent assay (ELISA). The results showed that 1 μg/mL LPS significantly activated the NF-κB signaling pathway, and resulted in optimized nuclear translocation of p65. CGMP at all investigated concentrations could inhibit the expression levels of inflammatory factors and angiogenic factors in HT-29 cells. Therefore, CGMP was capable of regulating the activated NF-κB signaling pathway and effectively restraining and improving the state of inflammation in colon cancer cells. This may be ascribed to inhibited expression of inflammatory cytokines and angiogenic factors, consequently reducing inflammation degree.

Key words: casein glycomacropeptide, colorectal carcinoma HT-29 cells, NF-κB, inflammatory cytokines, angiogenic factors