A cancer biomarker refers to a substance or process that is indicative of the presence of cancer in the body.
A biomarker may be a molecule secreted by a tumor or a specific response of the body to the presence of cancer. Genetic, epigenetic, proteomic, glycomic, and imaging biomarkers can be used for cancer diagnosis, prognosis, and epidemiology. Ideally, such biomarkers can be assayed in non-invasively collected biofluids like blood or serum.
Increasing evidence has revealed that lncRNAs will emerge as promising cancer biomarkers or therapeutic targets in cancer treatment. LncRNA-ATB, a Long non-coding RNA activated by TGF-β, was found to be abnormally expressed in certain cancers and participate in the development and progression of tumors. In addition, aberrant lncRNA-ATB expression was also associated with the clinical characteristics of tumors 1).
While numerous challenges exist in translating biomarker research into the clinical space; a number of gene and protein based biomarkers have already been used at some point in patient care; including, AFP (Liver Cancer), BCR-ABL (Chronic Myeloid Leukemia), BRCA1 / BRCA2 (Breast/Ovarian Cancer), BRAF V600E (Melanoma/Colorectal Cancer), CA-125 (Ovarian Cancer), CA19.9 (Pancreatic Cancer), CEA (Colorectal Cancer), EGFR (Non-small-cell lung carcinoma), HER-2 (Breast Cancer), KIT (Gastrointestinal stromal tumor), PSA (Prostate Specific Antigen) (Prostate Cancer), S100 (Melanoma), and many others.
Mutant Proteins themselves detected by Selected Reaction Monitoring (SRM) have been reported to be the most specific biomarkers for cancers because they can only come from an existing tumor.
see Glioma biomarker.