Dendritic cells vaccines activated by combined Toll-like receptor llgands inhibit murine colon cancer in vivo

Abstract

Objective To observe the anti-tumor effect of dentritic cells (DC) vaccine activated by combined Toll-like receptor (TLR) on murine colon cancer model and the survival time of tumor-bearing mice.Methods Murine colon cancers for the experiment were established using MC38-CEA and MC38 cells (1 × 106 cells per mouse).Seven days later,different DC vaccines (1 × 106 cells per mouse) were injected subcutaneously.The growth status of the subcutaneous tumors was observed twice per week and the survival was recorded.Finally the mean tumor volume in each group was analyzed for plotted curves and survival curves of mice in each group were depicted.Results In the MC38-CEA murine tumor model with preventive DC vaccine,mean tumor volume in the group of TLR activated DC pulsed with CEA peptide [ (1091.20 ±226.12) mm3] was significantly smaller than that of other groups (P ＜ 0.01 ) and the survival was significantly longer (P ＜ 0.01 ) ; When with therapeutic DC vaccine,the mean tumor volume of TLR + CEA-DC group [ (6487.20 ± 776.18 ) mm3 ] on the day 41 was smaller than that of PBS group [ (9361.20 ±2654.64) mm3 ] (P ＜0.05),but there was no difference from other groups (P ＞0.05).In the murine tumor model with MC38 colon cancer cells,mean tumor volume in all groups had no significant difference (P ＞ 0.05 ),and the survival time in each group had no significant difference ( P ＞ 0.05 ).Conclusion Combined TLR activated DC vaccine can inhibit the growth of MC38-CEA colon cancer cells and prolong survival days. Key words: Colon carcinoma; Dendritic cells; Toll-like receptor