Table 1.
Summary of recent findings of single-cell RNA-seq and bulk analysis of CTCs in CRC.
| Transcriptome | Type | Sample | Finding | Citation |
|---|---|---|---|---|
| Single cell analysis | Primary CRC | Primary CRC cells from CRC patients | Development of reference component analysis (RCA) which obtained seven distinct cell clusters (epithelial cells, fibroblasts, endothelial cells, B cells, T cells, mast cells and myeloid cells). | (Li et al., 2017) |
| Organoids from primary CRC human tumors (stage 1) | Detection of four newly emerged chemoresistant cell subtypes (c29, c30, c31, and c32) after Oxaliplatin treatment with different drug responses. | (Chen et al., 2018) | ||
| 2824 primary CRC cells from a CRC patient | Detection of five distinct cell clusters from a CRC patient with clear sign of heterogeneity, where each cluster consisted of specific cell markers with different functions. | (Dai et al., 2019) | ||
| Metastatic CRC | Metastatic single cells from CRC patients (stage III or IV) |
Confirmation of the feasibility of genetic lineages reconstruction together with their epigenomic and transcriptomic dynamics. | (Bian et al., 2018) | |
| CRC mouse model and metastatic mouse cancer cells | Validation of the dynamics of ITH in mouse CRC models and relate to CRC in humans via comparison with TCGA data. | (Ono et al., 2019) | ||
| Samples of liver metastasis cancer tissue and adjacent tissue from CRC patients | Identification of a total of 12 clusters corresponding to 6 cell types, including cancer cells, T cells, myeloid cells, endothelial cells, fibroblasts and B cells from patient sample of CRC liver metastasis. | (Zhang et al., 2019) | ||
| CRC cell line | Secondary cell line (HCT116 cells) | Identification of multiple adaptive resistance mechanisms to regorafenib in CRC via single cell RNA sequencing. | (Sathe et al., 2019) | |
| Bulk analysis | Metastatic CRC | EpCAM-based immunoisolation of CTC from 6 mCRC patients | Identification of 410 genes related to cell movement and adhesion, cell death and proliferation, and cell signaling and interaction via cDNA microarray. | (Barbazán et al., 2012) |
| CTC lines from the blood of 3 advanced mCRC patients | Validation of genetically and phenotypically heterogeneity in CTC lines. Identification of gene subset commonly enriched in cultured CTC and CTCs from colon and other cancers. CTC lines expressed high levels of drug metabolism genes and were resistant to conventional therapies. | (Grillet et al., 2017) |