Motile hepatocellular carcinoma cells preferentially secret sugar metabolism regulatory proteins via exosomes

Abstract

Exosomes are deliverers of critically functional proteins, capable of transforming target cells in numerous cancers, including hepatocellular carcinoma (HCC). We hypothesize that the motility of HCC cells can be featured by comparative proteome of exosomes. Hence, we performed the super-SILAC-based MS analysis on the exosomes secreted by three human HCC cell lines, including the non-motile Hep3B cell, and the motile 97H and LM3 cells. More than 1400 exosomal proteins were confidently quantified in each MS analysis with highly biological reproducibility. We justified that 469 and 443 exosomal proteins represented differentially expressed proteins (DEPs) in the 97H/Hep3B and LM3/Hep3B comparisons, respectively. These DEPs focused on sugar metabolism-centric canonical pathways per ingenuity pathway analysis, which was consistent with the gene ontology analysis on biological process enrichment. These pathways included glycolysis I, gluconeogenesis I and pentose phosphate pathways; and the DEPs enriched in these pathways could form a tightly connected network. By analyzing the relative abundance of proteins and translating mRNAs, we found significantly positive correlation between exosomes and cells. The involved exosomal proteins were again focusing on sugar metabolism. In conclusion, motile HCC cells tend to preferentially export more sugar metabolism-associated proteins via exosomes that differentiate them from non-motile HCC cells.

A new role for extracellular vesicles: how small vesicles can feed tumors' big appetite

“…Indeed, it has been shown that glycolytic enzymes found within prostate-derived EVs are functional inside the vesicles and can generate ATP upon incubation with their substrates (87) and that this process is required for EV uptake (88). As glycolytic enzymes were found to be more abundant in the EVs secreted by aggressive cancer cells, these vesicles may be more efficiently taken up by recipient cells, leading to an increased transfer of material (86). Nevertheless, the presence of glycolytic enzymes in EVs is not necessarily associated with a functional transfer.…”

“…Indeed, in a study aiming to compare the exoproteome of a nonaggressive vs an aggressive hepatocellular carcinoma cell line, aggressive cell-derived EVs are enriched in sugar-related metabolic pathways, namely glycolysis, gluconeogenesis and pentose phosphate pathways (86). Hence, transfer of glycolytic enzymes between cancer cells may impact the metabolism of recipient cells.…”

Exploring the key communicator role of exosomes in cancer microenvironment through proteomics

“…In-Gel Digestion [33][34][35][36][37] FASP [38,39] Combined method In-Gel Digestion [28,35,36,[40][41][42][43][44][45][46][47][48][49][50][51] In-Sol Digestion [52][53][54] FASP [51,[55][56][57][58][59] Plasma/ Serum Ultracentrifuge In-Sol Digestion [60] FASP [56] Combined method In-Gel Digestion [43] In-Sol Digestion [44,52] FASP [51,57,58] secreted by MCF7, 30 proteins have been known to participate in breast cancer growth, metastasis, and chemoresistance. The most abundant MDA-MD-231 derived exosomal protein is β-actin, which is frequently used as a housekeeping gene in the exosome.…”

Exosome-based liquid biopsy in the management of hepatocellular carcinoma

“…Differential ultracentrifugation is considered the gold standard method for purification of exosomes and most of the studies have applied this technique for isolating HCC-derived exosomes [27,28] . However, depending on the starting material and downstream applications, other methods for the purification and enrichment of HCC-derived exosomes have also been used such as ultrafiltration, size exclusion chromatography (SEC) or the ExoQuick TC method [19,29] .…”

“…Motile behaviour in MIHA cells was triggered by activation of PI3K/AKT and MAPK signalling pathways which in turn increased secretion of active matrix metalloproteinase, MMP-2 and MMP-9 [56] . A comparative proteome analysis of exosomes from the non-motile Hep3B cell, and the motile 97H and LM3 cells found the motile HCC cells to secrete more sugar metabolism regulatory proteins via exosomes in the tumour microenvironment [28] . The ability of exosomes to modulate the motile ability of tumour cells was tested by comparing protein profiles of cell lines with distinct metastatic potential.…”