Proteomics Clin Appl. 2020 Oct 24:e2000056. doi: 10.1002/prca.202000056. Online ahead of print.
PURPOSE: The prognosis for colorectal cancer (CRC) patients is drastically impacted by the presence of lymph node or liver metastases at diagnosis or resection. On this basis we sought to identify novel proteins as biomarkers and determinants of CRC metastasis.
EXPERIMENTAL DESIGN: Proteomic analyses were undertaken using primary tissues from ten Chinese CRC patients presenting with or without liver metastases and immunohistochemistry used to validate selected proteins in an independent patient cohort.
RESULTS: Comparing CRC against paired normal adjacent tissues identified 1559 differentially expressed proteins (DEPs) with 974 upregulated and 585 downregulated proteins, respectively. The highest number of DEPs was selectively associated with metastatic tumors (519 upregulated and 267 downregulated proteins, respectively) with a smaller number of unique DEPs identified only in non-metastatic CRC cases (116 upregulated and 29 downregulated proteins, respectively). The remaining DEPs were commonly expressed in both non-metastatic and metastatic tumors. The upregulation of three representative DEPs (S100A11, S100P and RBM25) was confirmed using immunohistochemistry against 154 CRC tissues embedded in a tissue microarray (TMA).
CONCLUSIONS AND CLINICAL RELEVANCE: Our data reveals both previously identified CRC biomarkers along with novel candidates which provides a ready resource of DEPs in CRC for further investigation. This article is protected by copyright. All rights reserved.