Protein patterns in blood may predict prostate cancer diagnosis

HomeScience ReportsReports and NewsHealth and Medicine

Protein patterns in blood may predict prostate cancer diagnosis

16.10.2002

Patterns of proteins found in patients’ blood serum may help distinguish between prostate cancer and benign conditions, scientists from the National Cancer Institute (NCI) and the Food and Drug Administration (FDA) report today in the Journal of the National Cancer Institute*. The technique, which relies on a simple test using a drop of blood, may be useful in deciding whether to perform a biopsy in men with elevated prostate specific antigen (PSA) levels.

Using a test that can analyze the patterns of small proteins in blood serum samples in just 30 minutes, researchers were able to differentiate between samples taken from patients diagnosed with cancer and those from patients diagnosed with benign prostate disease. The technique proved effective not only in men with normal and high PSA levels, but also in those whose PSA levels were marginally elevated (4 to 10 nanograms of antigen per milliliter of fluid), in whom it is difficult to rule out cancer without a biopsy.

Although the technique is still under evaluation, researchers believe the analysis of protein patterns will be a useful tool in the future for deciding whether men with marginally elevated PSA levels should undergo biopsy. PSA levels are commonly used as a preliminary screen for prostate cancer, but 70 percent to 75 percent of men who undergo biopsy because of an abnormal PSA level do not have cancer. The new proteomic approach has a higher specificity - that is, of the samples the test identifies as cancer, a large percentage are in fact cancer, rather than some other benign disease.

"For men with marginally elevated PSA levels, the specificity of the test is 71 percent, as opposed to a very low specificity for PSA in this range," said Emanuel Petricoin III, Ph.D., of the FDA’s Center for Biologics Evaluation and Research, the first author of the study. "We hope that by using proteomic pattern analysis screening in combination with other screening methods, we can reduce the number of unnecessary biopsies for prostate cancer in the future."

The diagnostic test relied on computer software that detects key patterns of small proteins in the blood. Researchers analyzed serum proteins with mass spectroscopy, a technique used to sort proteins and other molecules based on their weight and electrical charge. They then used an artificial intelligence program developed by Correlogic Systems, Inc., in Bethesda, Md., to train a computer to identify patterns of proteins that differed between patients with prostate cancer and those in which a biopsy had found no evidence of disease. These patterns were identified using serum samples from 56 patients who had undergone a biopsy and whose disease status was known.

Once established, the protein patterns were then used to predict diagnosis in a separate group of patients, whose biopsy results were not known by the researchers. From this group, researchers were able to correctly identify 36 of 38 (95 percent) cases of prostate cancer and 177 of 228 (78 percent) cases of benign disease.

The study follows up on the recent finding by the same research group that protein patterns in serum can be used to detect ovarian cancer.

"We have now demonstrated that combining proteomic technology with artificial intelligence based bioinformatics can be a powerful tool, and is a new paradigm in the detection and diagnosis of both ovarian and prostate cancers," said Lance Liotta, M.D., Ph.D., the senior investigator on the study from NCI’s Center for Cancer Research. "We are extremely optimistic that this new approach will prove useful in detecting and diagnosing many other cancers and diseases in the future."

NCI Press Office | EurekAlert!
Further information:
http://www.cancer.gov.

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New Pitt research finds carbon nanotubes show a love/hate relationship with water

Carbon nanotubes (CNTs) are valuable for a wide variety of applications. Made of graphene sheets rolled into tubes 10,000 times smaller than a human hair, CNTs have an exceptional strength-to-mass ratio and excellent thermal and electrical properties. These features make them ideal for a range of applications, including supercapacitors, interconnects, adhesives, particle trapping and structural color.

New research reveals even more potential for CNTs: as a coating, they can both repel and hold water in place, a useful property for applications like printing,...

Im Focus: Magnets for the second dimension

If you've ever tried to put several really strong, small cube magnets right next to each other on a magnetic board, you'll know that you just can't do it. What happens is that the magnets always arrange themselves in a column sticking out vertically from the magnetic board. Moreover, it's almost impossible to join several rows of these magnets together to form a flat surface. That's because magnets are dipolar. Equal poles repel each other, with the north pole of one magnet always attaching itself to the south pole of another and vice versa. This explains why they form a column with all the magnets aligned the same way.

Now, scientists at ETH Zurich have managed to create magnetic building blocks in the shape of cubes that - for the first time ever - can be joined together to...

Im Focus: A new quantum data classification protocol brings us nearer to a future 'quantum internet'

The algorithm represents a first step in the automated learning of quantum information networks

Quantum-based communication and computation technologies promise unprecedented applications, such as unconditionally secure communications, ultra-precise...

Im Focus: Distorted Atoms

In two experiments performed at the free-electron laser FLASH in Hamburg a cooperation led by physicists from the Heidelberg Max Planck Institute for Nuclear physics (MPIK) demonstrated strongly-driven nonlinear interaction of ultrashort extreme-ultraviolet (XUV) laser pulses with atoms and ions. The powerful excitation of an electron pair in helium was found to compete with the ultrafast decay, which temporarily may even lead to population inversion. Resonant transitions in doubly charged neon ions were shifted in energy, and observed by XUV-XUV pump-probe transient absorption spectroscopy.

An international team led by physicists from the MPIK reports on new results for efficient two-electron excitations in helium driven by strong and ultrashort...

Im Focus: A Memory Effect at Single-Atom Level

An international research group has observed new quantum properties on an artificial giant atom and has now published its results in the high-ranking journal Nature Physics. The quantum system under investigation apparently has a memory - a new finding that could be used to build a quantum computer.

The research group, consisting of German, Swedish and Indian scientists, has investigated an artificial quantum system and found new properties.

All Focus news of the innovation-report >>>

Top

Send this article

Forum for Science, Industry and Business