Table 1.

Analysis of CTCs

Analysis	Techniques	Markers	References
Count	Stain	Antibodies against cytokeratins	[70]
DNA-based strategies	Sanger sequencing	PIK3CA and EGFR	[71]
	Next-generation sequencing	The complete exome and genome	[72-74]
	Multiple displacement amplification	Single nucleotide polymorphism	[72]
	Comparative array genomic hybridization	Genomic profiling of CTCs	[75]
mRNA-based strategies	Reverse-transcription PCR	CK18, CK19, CK20, MUC1, prostate-specific antigen, and carcinoembryonic antigen	[76]
	Digital PCR	ATP	[77]
	RNA sequencing	Wnt2	[78]
	Multicolor RNA in situ hybridization	Multiple gene targets	[79]
Protein-based strategies	Mass cytometry	Phosphorylation states	[80-82]
	CellSearch	CKs, CD45, and DAPI	[76]
	Epithelial ImmunoSPOT	Secreted, shed, or released proteins	[83]
	High-speed automated digital microscopy	Antibodies with fluorescent conjugates	[84]
	Microfluidic technologies		[85]
	Mass spectrometry approaches		[82]