Fig. 2.

Cells and various factors are shed by the tumor into the circulation that can be harnessed for liquid biopsy. Blood, CSF, and urine are the analytes that can be targeted. Usually, CTCs can give a glimpse of various abnormalities associated with DNA, RNA, proteins. ctDNA can be targeted to infer mutations, translocation, deletion, or amplification. Exosomes are enriched with metabolites and proteins besides various non-coding RNAs which can be present in cell-free form too. High throughput technologies like NGS, single-cell sequencing, proteomics, epigenetics, and metabolomics can unfurl these target biomolecules, which can be implicative in BrM