2-deoxy-2-18 F-fluoro-D-glucose uptake capability of human colorectal cancer cells and colorectal cancer associated fibroblasts

Abstract

Objective To investigate the capability of 2-deoxy-2-18F-fluoro-D-glucose (18F-FDG) uptake by human colorectal cancer cells and colorectal cancer associated fibroblasts (CCAFs) before and after co-culture of these two kinds of cells and to explore the characteristics of glucose metabolism of CCAFs.Methods The binding conditions of CCAFs and 18F-FDG were opitimized regarding to cells count (1 ×104,5 ×104,1 ×105,3 ×105,5 ×105),reaction time (40,60,80,100,120 min),radioactivity of 18F-FDG (1.85,3.70,7.40,14.80,29.60 kBq) and initial glucose concentration (0,2.78,5.55,11.10 mmol/L).The uptake of 18F-FDG by Caco-2,HCT116 and CCAFs was determined before and after co-culture of CCAFs-cancer cells.Results The optimal conditions of 18F-FDG binding were as follows:cell counts 5 × 105/wefl,reaction time 100 min,radioactivity of 18F-FDG 3.70 kBq and initial glucose concentration 0 mmol/L,and the 18F-FDG cells binding ratio of CCAFs was (42.80 ±4.47)％.Before and after co-culture,the 18F-FDG binding ratio of Caco-2 was (28.6500± 4.7600)％,and (18.821 5± 1.5100)％ (P＜ 0.05),and that of HCT116 was (24.9743± 2.8300)％,and (17.720 2 ± 2.620 0) ％ (P ＜ 0.05).No significant change in 1s F-FDG binding by CCAFs was observed.Conclusion The uptake capability of 18F-FDG by CCAFs was sinifiantly higher than colorectal cancer cells.Co-culture with CCAFs siginificantly suppressed the uptake of colorectal cancer cells.CCAFs may be a very important component in the enhanced uptake of glucose in colorectal cancer. Key words: Colorectal cancer associated fibroblasts; 2-deoxy-2-18F-fluoro-D-glucose; Coculture