By Larry Hand
March 1, 2008 | Molecular diagnostics and molecular imaging for diagnostics are benefiting greatly from research since the completion of the Human Genome Project. Biomarkers are playing increasingly important roles, and one disease area, cancer, is getting much attention in this regard.
Technologies such as DNA microarrays are being used to analyze biological samples in molecular diagnostics to identify high risk patients, predict response to therapy, and monitor patients during treatment to either determine effectiveness of treatment or detect recurrence of disease. Numerous companies are developing molecular oncology diagnostics tests.
Oncology is considered the most promising area of research in molecular diagnostics, according to respondents to an online survey conducted last year. Of 253 respondents, 86 (34%) cited oncology, 67 (26.4%) cited pharmacogenomics, and 37 (14.6%) cited infectious disease.
Two examples of such tests are Oncotype DX from Genomic Health in Redwood City, Calif., and the MammaPrint test from Agendia, based in Amsterdam. Oncotype DX evaluates expression of 21 cancer-related genes and provides a patient with an assessment of likelihood that breast cancer will return. MammaPrint gives a profile of the expression of 70 genes involved in some aspect of cancer such as metastasis or angiogenesis.
Some upcoming diagnostics tests are based on DNA methylation, an epigenetic process that influences gene expression, and the use of PCR. These include a blood-based early detection colorectal test and a tissue-based prostate molecular classification assay from Epigenomics (Berlin, Germany and Seattle, Wash.), in addition to tissue-based and urine-based early diagnostic tests for prostate cancer from OncoMethlome Sciences (Leuven, Belgium and Durham, N.C.). Both companies’ tests could gain U.S. or European regulatory approval this year.
In an interview last year, two Epigenomics executives, Geert Walther Nygaard and Oliver Schacht, explained how their technology will improve the cancer outlook: “DNA methylation biomarkers are present at very early stages of cancer development, and you can detect them from body fluids such as blood, plasma, and urine. That allows the organ-specific detection of cancer from a minimally invasive patient sample. This is unique. A lot of cancer biomarkers are cancer markers, but they are not colon cancer markers, for example. We have found that methylation offers the ability to have an organ-specific, cancer-specific test.”
In Vitro to In Vivo
Developments in “omics” technologies over the past decade have driven a search for new in vitro biomarkers that are associated with expressed genes, proteins, or metabolites. This has led further to increased interest in biomarkers for imaging. In addition to their in vitro usefulness, biomarkers can refer to morphological, functional, or molecular measurements made in vivo through medical imaging. These technologies include computed tomography, magnetic resonance imaging, positron emission tomography (PET), ultrasound, and optical scanning.
PET, which involves injecting a compound containing a radioisotope into the body and then imaging the body to detect the compound at its targeted location, is the most widely used technology for biomarker studies at present. PET’s resolution gets down to the 100-picomolar level in targeted tissues, a level at which compounds often have little or no ill physiological consequences. Another form of PET, fluorodeoxyglucose (FDG)-PET, is proving useful in both oncology drug development and diagnostic applications such as diagnosis, staging, monitoring, and prognostication. FDG-PET has been useful in detecting recurrence in an especially vexing cancer, ovarian.
Although advances in molecular diagnostics and imaging will continue to impact cancer, this is by no means where all the effort is. In molecular diagnostics, infectious disease continues to be a large part of the market. Genetic testing is another major area of molecular diagnostics, and the advancement of personalized medicine is also a major goal.
Larry Hand is editorial director at CHI’s Insight Pharma Reports. He can be reached at email@example.com.
This commentary is based on two recent reports published by Insight Pharma Reports: Molecular Diagnostics: A Rapidly Shifting Commercial and Technology Landscape by Lucy Sannes, PhD; and
Molecular Imaging in Drug R&D and Medical Practice: Technologies, Applications, Markets by Ken Rubenstein, PhD.
For more information on the reports, go to www.insightpharmareports.com.
This article appeared in Bio-IT World Magazine.
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