Comparison of urine proteomes from tumor-bearing mice with those from tumor-resected mice

[Objective] This study focuses on the most important concern of surgeons - whether they resected all of the tumor. Urine can reflect early changes associated with physiological or pathophysiological processes. Based on the above ideas, we conducted experiments to explore changes in the urine proteome between tumor-bearing mice and tumor-resected mice. [Method] The tumor-bearing mouse model was established with MC38 mouse colon cancer cells, and the mice were divided into the healthy control group, complete resection group, and nonresection group. Urine was collected 7 days and 30 days after resection. Liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) was used to identify the urine proteome and then analyze differentially expressed proteins and biological pathways. [Results] (1) Seven days after tumor resection, there were 20 differentially expressed proteins that could distinguish between the complete resection group and the nonresection group. The biological process includes circadian rhythm, Notch signaling pathway, leukocyte cell–cell adhesion, and heterophilic cell–cell adhesion via plasma membrane cell adhesion molecules. (2) Thirty days after tumor resection, there were 33 differentially expressed proteins that could distinguish between the complete resection group and the nonresection group. The biological process includes cell adhesion, complement activation, the alternative pathway, the immune system process, and angiogenesis. (3) There was no significant difference between the two groups at 30 days after tumor resection between the complete resection group and the healthy control group. [Conclusion] Changes in the urine proteome can reflect tumors with or without complete resection.