CD40 signaling activated by agonistic anti-CD40 monoclonal antibody 5C11 has different effects on biological behavior of gastric carcinoma cells.

A gastric cancer cell line, AGS has high-level expression of CD40. CD40 is present on the surfaces of a large variety of cells, including B cells, endothelial cells, dendritic cells and some carcinoma cells, and delivers signals regulating diverse cellular responses, such as proliferation, differentiation, growth suppression, cell death. In this research, the expression of CD40 and CD40 transcription in gastric cancer cell lines (AGS, BGC-823, HGC-27, SGC-7901) was investigated by semi-quantitative RT-PCR. Cancer cell proliferation inhibitory assay was also performed using different concentrations of anti-CD40 monoclonal antibody (mAb), 5C11. Results indicated that treatment of 5C11 alone and combined 5C11, IFN-alpha and 5-FU both significantly inhibited cancer cell proliferation. The synergistic effects of combined 5C11, IFN-alpha and 5-FU on growth inhibition of human gastric cancer AGS cells could be observed. These results suggest that humanized anti-CD40 monoclonal antibody (mAb), 5C11 can be used as a valuable reagent for clinical application.