Biomarkers in Cancer
A biomarker is a biomolecule that is an indicator of normal health or disease in the body. A biomarker can be DNA in a gene, mRNA, an enzyme or a protein. The presence of a disease and its magnitude can be inferred by measuring the concentration of the associated biomarkers in blood or tissues.
Cancer is a complex disease that develops gradually over time with accumulation of genetic mutations leading to abnormal expression of enzymes or proteins that control cell growth, proliferation, differentiation and death. The biomarkers of cancercan be measured at the genetic level (mutations, deletions, insertions, chromosomal aberrations, copy number variations, duplications), mRNA level (high or low expression), and at the enzyme or protein level (over expression, abnormal expression, absence of expression), and at cellular level (circulating tumor cells, cancer stem cells).
In cancer drug discovery, biomarkers are used to measure the efficacy and potency of targeted lead compounds or clinical drug candidates in in vitro cell models and in animal models to demonstrate pharmacokinetic-pharmacodynamic (PK/PD) relationships and proof of concept. Only candidate drugs which show correlations between biomarkers and efficacy are progressed into development. Biomarkers serve as surrogate clinical measures to support a clinical endpoint in all the phases of clinical trials. A drug candidate that does not demonstrate PK/PD (biomarker) correlations in late stage clinical trials is likely to fail in the clinic.
In treatment of cancer, biomarkers are used to detect, diagnose, stratify, selection of therapies, monitor clinical response or failure and to evaluate toxicities. Biomarkers can be measured using biochemical assays such as spectrophotometry, ELISA (Enzyme Linked Immunosorbent Assay), histopathology, IHC (immunohistochemistry), Western blotting, gene sequencing, enzyme activity, and imaging.
OncoDynamiX uses its novel platform technologies OncembleX to analyse biomarker data (genomics, transcriptomics, proteomics) from cancer patients and recommends treatment strategies appropriate for individual patients.
- American Association of Cancer Research, Cancer Progress Report, 2021