"This is good news in an area where our ability to diagnose and predict has previously been less than stellar," said Krishna Donkena, Ph.D., Mayo Clinic urologic researcher. "Our only tool is the PSA test, which has little predictive value. These findings move us much closer to a more accurate test."
The search to identify biomarkers that can be translated into affordable and effective medical tests can be complicated. Prostate cancer causes differential expression of hundreds of different genes, each potentially an indicator of whether a man may get the disease, or already has it. They also may be used to provide information on the development of the cancer, without the need for a painful tumor biopsy.
When seeking to narrow their search to a manageable level, the researchers analyzed 32 cancerous and eight benign patient-tissue samples using genome microarrays representing 33,000 human genes. The information they gleaned from this analysis allowed them to identify 624 differentially-expressed genes between cancerous and benign tissue. They validated these findings in the original 40 tissue samples as well as in 32 additional samples (20 cancerous, 12 benign). The results showed eight genes with significant under-expression and three with significant over-expression, strongly implicating them in prostate cancer development and progression.
Over the years, research has shown that DNA methylation is commonly linked to the development and progression of cancers. This epi-genetic alteration results in silencing or seriously inhibiting gene expression, which in turn lessens the body’s ability to defend against cancer. Current research has not done enough to discover ways to convert this information into a useful medical test, in large part due to the limited number of genes that have been thoroughly studied, and their insufficient sensitivity and specificity (probability of getting a true positive or true negative) for prostate cancer detection.
Dr. Donkena’s team looked at 62 cancerous and 36 benign tissue samples to assess the degree of methylation in the three previously identified under-expressed genes, comparing two known methylated genes. They determined that one gene, PDLIM4, had hypermethylation that could serve as an effective sensitivity marker, accurately detecting prostate cancer 95 percent of the time. The researchers further determined that the combined measurement of a previously known gene, GSTP1, and PDLIM4 improved the detection rate to 98 percent.
Prostate cancer is the second leading cause of cancer death for men in the United States, exceeded only by lung cancer. The sooner a cancer can be diagnosed, the better treatment outcomes will be, so Dr. Donkena and her colleagues are constantly looking for ways to predict who will get prostate cancer, as well as to find better ways to diagnose early or even prevent this disabling and often fatal disease. "We hope that in addition to being a valuable diagnostic and prognostic tool, our discoveries about these genes will help us develop new treatments for prostate cancer," she said.
Other Mayo researchers involved in this study include Karla Ballman, Ph.D.; Bruce Morlan; John Cheville, M.D.; Roxann Neumann; Michael Lieber, M.D.; Donald Tindall, Ph.D.; and Charles Young, Ph.D.
Elizabeth Zimmermann | EurekAlert!
Link Discovered between Immune System, Brain Structure and Memory
26.04.2017 | Universität Basel
Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown University
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
26.04.2017 | Materials Sciences
26.04.2017 | Agricultural and Forestry Science
26.04.2017 | Physics and Astronomy