Metabolomic study on the effects of insulin and oleic acid on the development of colon cancer xenografts

To investigate the regulatory effects of insulin and oleic acid on serum metabolites in colon cancer, subcutaneous transplantation tumor model of colon carcinoma cell HCT116 was established. Nude mice were randomly divided into 4 groups: control (CON, vehicle); insulin treatment (INS, sc, 2.5 U/kg); oleic acid treatment (OA, ig, 2.0 g/kg); and insulin (sc, 2.5 U/kg) plus oleic acid (ig, 2.0 g/kg) treatment (IO). Non-target metabolomic analysis on the blood samples was performed by GC/MS and LC-IT-TOF/MS. Data pre-processing, including peaking, spectral deconvolution and peak alignment, was performed before data were imported to SIMCA-P for multivariate statistical analysis. Results showed that body weight of individuals in IO group was the lowest, but the tumor weight was the heaviest. Metabolic profiles of IO group were also different compared with the CON group, and the contributing metabolites were urea, arabinose, cholesterol, L-acetylcarnitine and sphingosine. There was no significant difference between OA or INS and CON. This study showed that the combination of insulin and oleic acid promoted colon cancer deterioration and caused metabolic disturbance in blood.Our study may provide theoretical foundation for the discovery of colon cancer biomarker and its early diagnosis.