Carbon-ion Evokes Metabolic Reprogramming and Individualized Response in Prostate Cancer

Abstract Background: Carbon ion radiotherapy (CIRT) is a novel and powerful tool for prostate cancer (PCa). However, the underlying mechanism for individualized treatment response after CIRT was not clear, and there was still no effective indicator to timely demonstrate the treatment response. Metabolic reprogramming is one of the main hallmarks of malignancy. Metabolic status might have a high relationship with the radiosensitivity and the individualized radiation response. The significant changes of metabolites profiles were detected after radiotherapy in the serum sample of different malignancies. But there was limited data regarding CIRT induced metabolic changes in prostate cancer. Our aim was to preliminary investigate the carbon-ion induced metabolic reprogramming in PCa patients and the individualized response of PCa patients to carbon ion. Methods: Urine samples collected from 15 pathology confirmed PCa patients before and after CIRT were enrolled into this analysis. High-throughput UPLC-MS/MS system was used for metabolites detection. XCMS online, MetDNA and MSDIAL were used for peak detection and identification of metabolites. Statistical analysis and metabolic pathway analysis were performed on Metaboanalyst.Results: A total of 1701 metabolites were monitored by high-throughput UPLC-MS/MS and 217 metabolites were identified. The PCA scores plot revealed clear discrimination of the patient’s urine metabolites profiles before (pre-CIRT) and after (pre-CIRT) CIRT treatment. 35 metabolites significantly altered after CIRT, and these metabolites mainly were amino acid. Pathway enrichment analysis further identified these metabolites could be enriched in 8 pathways (FDR<0.05, impact>2), while arginine biosynthesis and histidine metabolism pathways were the most significant. In addition, the HCA shows that after CIRT, the patients can be clustered into two groups according to the metabolites profiles. The discriminatory metabolites after CIRT in patients urine mainly enriched in the pathway of arginine biosynthesis and phenylalanine, tyrosine, and tryptophan biosynthesis. Conclusion: Metabolic reprogramming and metabolic inhibition seems one of the most important mechanisms of CIRT to cure PCa. Urine metabolites also showed their potentials to timely identify the individualized response of PCa patients to CIRT.