Molecular profiling

Combines molecular medicine and bioinformatics to select the most appropriate therapy for patients with cancer.

Rather than identifying a cancer on the basis of morphological appearance of the cells and the environs, molecular characterization allows for classifications by determining the level of gene and protein expression within the malignancy and comparing that expression patterns. with the expression profiles of cancers with known outcomes.

Using algorithms the cancer is placed in outcome class derived from similar expression profiles to yield a survival probability.

Refers to the assessment of DNA, RNA, and/or proteins with in an individual patient’s cancer using cells obtained from a tumor biopsy or through the capture of tumor cells circulating in the blood stream.

Molecular profiling techniques include: polymerase chain reaction, in situ hybridization, chromogenic in situ hybridization, Sanger sequencing, NGS, Pyrosequencing, Fragment analysis.

Polymerase chain reaction is used to amplify and detect DNA and RNA sequences. It involves amplification or one or more copies of the chosen DNA sequence to produce millions of copies and enable detection analysis. Reverse transcription PCR converts RNA templates into complementary DNA for molecular analysis.

In DNA, gene copy number abnormalities, gains or losses, and structural variants such as translocations/rearrangements can be analyzed, as well as small DNA mutation sequence changes.

DNA changes often present as single nucleotide variants or insertions or deletions of small numbers of base pairs within a gene.

Gene mutations can cause gain or loss of function, and can regulate transcription of the gene or stability of the RNA transcript.
Expression of gene RNA or protein gene products can be evaluated by their presence, or quantified by the amount of RNA or proteins expressed.
Copy number gains and losses can be analyzed using routine karyotyping, florescence in situ hybridization (FISH), DNA microarrays, or next generation sequencing (NGS).
Structural variants characterized by movement of genes or chromosomes within the genome, can be found by karyotyping, FISH, PCR-based essays, either at the DNA or RNA level or via reverse transcriptase PCR, and NGS-based methods.
In  a study of 200 patients with cancer of unknown primary 96% of cases had an actionable mutation detected via comprehensive genomic profiling (Ross JS).


Leave a Reply

Your email address will not be published. Required fields are marked *