Table 3.
Tumor microenvironment-derived markers in liquid biopsy of mCRC.
| Clinical Association | Reference | |
|---|---|---|
| Circulating endothelial progenitors, circulating endothelial cells and tumor angiogenic markers | ||
| Circulating endothelial cells | Prognostic biomarkers in CRC | [74,75] |
| Number of circulating endothelial cells and progenitors | Decreased in bevacizumab-treated patients with radiological response | [76] |
| ↓ circulating progenitor and endothelial cells | Association with longer progression-free survival and overall survival of bevacizumab combination chemotherapy treated mCRC patients | [77,78] |
| Circulating endothelial cells | Association with survival in bevacizumab-based first-line treated patients | [79] |
| Angiogenic switch | Association with progression free survival | [80] |
| VEGF-D plasma concentration | Predictive value for ramucirumab efficacy | [81] |
| VEGF-A and ICAM-1 variants | Prognosis value in bevacizumab treated patients | [82] |
| VEGF, HGF, EGF, and PDGF-AA levels | Predictive value in chemotherapy-based treated patients | [83] |
| Circulating immune cells and inflammatory related markers | ||
| ↑ immune-inflammation index | Association with poor clinical outcomes | [84,85] |
| Immune-inflammation index | Predictive marker for mCRC patients | [86] |
| ↑ EGF, macrophage-derived chemokine and ↓ IL-10, IL-6 and IL-8 levels | Predictive value in irinotecan/bevacizumab-based treatments | [87] |
| ↓ mean platelet volume and in the platelet-to-lymphocyte ratio | Association with worse overall survival | [88,89] |
| ↓ platelet-to-lymphocyte ratio | Predictor of aflibercept response | [90] |
| Neutrophil-lymphocyte ratio, platelet-lymphocyte ratio and systemic immune inflammation index are | Predictors oof cetuximab-combined therapy | [91] |
| Neutrophil-lymphocyte ratio | Predictor of good response | [92,93,94,95] |
| ↑ monocyte-lymphocyte ratio | Worse outcome | [96] |
| ↓ T cells subsets | Association with better outcome | [97] |
| Levels of Treg and T helper rate | Association with therapeutic response | [98] |
| Quantification of Tregs and CD8+ T cells | Prognostic value | [99] |
| Exosomes and noncoding-RNAs | ||
| miR-92a-3p | Association with metastatic status and chemotherapy predictive value | [100] |
Footnotes: ↓ Downregulation/low levels; ↑ Upregulation/high levels.