Cancer Profiling Technologies
Caris Life Sciences uses multiple profiling technologies — including IHC, DNA and next-generation sequencing, PCR, and FISH/CISH — in order to detect and interrogate each biomarker. Coupled with an exhaustive, evidence-based review of literature, the results of these advanced tests can aid physicians in individualizing cancer treatment.
What are DNA sequencing, next-generation sequencing (NGS) and PCR and what information can they provide?
Single nucleotide changes and small deletions and insertions in a DNA coding sequence (typically referred to as mutations) can impact the function of the associated protein, causing it to contribute to cancer progression or altering the sensitivity to certain anti-cancer chemotherapy agents. DNA sequencing is a method that can be employed to detect mutations within a sample. PCR is used as an initial step to isolate and amplify specific regions of the genome typically referred to as amplicons. DNA sequencing is then performed to determine the nucleic acid sequence that is then compared to a reference sequence to identify mutations. NGS allows for multiple amplicons to be analyzed hundreds or thousands of times in a parallel fashion to detect the presence of mutations in a sample.
What are FISH and CISH and what information can they provide?
FISH, or fluorescence in situ hybridization, is a microscopic technique that uses specific DNA sequences tagged with fluorophores to detect and localize the corresponding genes on chromosomes within a cell. The probes only detect genes with a high degree of homology. CISH, or chromogenic in situ hybridization, uses chromogenic dyes instead of fluorophores to aid in gene amplification analysis. Both techniques are used to determine gene copy number variations, translocations and gene fusions.
What is IHC and what information can it provide?
IHC, or immunohistochemistry staining, allows biomarkers to be detected in cells by using color-producing antibodies that specifically bind to protein biomarkers. Color produced by the antibody-bound biomarkers in cells can be viewed under a microscope by a molecular pathologist. The intensity and percentage of the staining in the tumor tissue is used to confirm whether the particular biomarker is overexpressed.