Oral squamous cell carcinoma (OSCC) has high mortality rates that are largely associated with lymph node metastasis. However, the molecular mechanisms that drive OSCC metastasis are unknown. Extracellular vesicles (EVs) are membrane-bound particles that play a role in intercellular communication and impact cancer development and progression. Thus, profiling EVs would be of great significance to decipher their role in OSCC metastasis. For that purpose, we used a reductionist approach to map the proteomic, miRNA, metabolomic, and lipidomic profiles of EVs derived from human primary tumor (SCC-9) cells and matched lymph node metastatic (LN1) cells. Distinct omics profiles were associated with the metastatic phenotype, including 670 proteins, 217 miRNAs, 26 metabolites, and 63 lipids differentially abundant between LN1- and SCC-9-derived EVs. A multi-omics integration identified 11 ‘hub proteins’ significantly decreased at the metastatic site compared to primary tumor-derived EVs. We confirmed the validity of these findings with analysis of data from multiple public databases, and found that low abundance of seven ‘hub proteins’ in EVs from metastatic lymph nodes (ALDH7A1, CAD, CANT1, GOT1, MTHFD1, PYGB and SARS) is correlated with reduced survival and tumor aggressiveness in cancer patients. In summary, this multi-omics approach identified proteins transported by EVs that are associated with metastasis, and which may potentially serve as prognostic markers in OSCC.
Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.