Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Blood proteins to detect ovarian cancer

16.08.2004


Johns Hopkins Kimmel Cancer Center researchers have designed a blood test to detect ovarian cancer using three proteins found in common in the blood of women with the disease. Their preliminary studies with the new test suggest a molecular signature exclusive to this deadly cancer, known for its ability to remain undetected and spread quickly.



The Hopkins test, described in the August 15 issue of Cancer Research, identifies the proteins as a truncated form of transthyretin, a fragment of ITIH4 and apolipoprotein A1, teased out with a rigorous evaluation of protein patterns present in blood samples from ovarian cancer patients at several U.S. and international hospitals. Other research groups are evaluating ovarian cancer blood tests that use protein profiles consisting of tens of thousands of unidentified molecules.

"By identifying a select group of biomarkers specific to ovarian cancer, we not only know the proteins we are dealing with, but we can trace them back to alterations in the genetic code of ovarian cancer cells," says Daniel W. Chan, Ph.D., professor and director of the Biomarker Discovery Center at Johns Hopkins. "We are focusing on the markers for which we have good biological reasoning behind their selection, and hope to expand the panel of markers to catch as many variations in ovarian cancer proteins as possible."


This research was funded by the National Cancer Institute and Ciphergen Biosystems, which has licensed the test.

Chan and his co-workers emphasize that the test will not be commercially available for screening the population at large until completion of further validation studies in larger groups of patients. And even then, Chan notes, it is never going to be possible for a blood test to correctly diagnose 100 percent of cancerous tumors 100 percent of the time. "The goal is to come as close as possible to that by using this test in combination with other available diagnostic tools." They believe, however, that with some refinements it may already have use for helping determine whether a pelvic mass is ovarian cancer.

In a systematic search to find the most promising blood proteins for their test, the Hopkins scientists conducted a multicenter study and screened a total of 195 blood samples from two groups of ovarian cancer patients, healthy people, and patients with benign ovarian tumors. A sophisticated bioinformatics program was used to select proteins present at unusually high or low levels in ovarian cancer samples as compared with normal or benign. Samples in the two groups were analyzed separately to account for differences in patient populations and sample collection techniques. Then, researchers compared protein profile results in these two groups and ultimately narrowed the search for potential marker candidates to the three proteins, one of which (ITIH4) is commonly found at high levels in ovarian cancer and the other two at lower levels.

"Typically, only half of early-stage ovarian cancer patients have high blood levels of a standard marker called CA125," says Zhen Zhang, Ph.D., associate professor of pathology at Johns Hopkins. "But combining CA125 with our new markers may improve early detection capabilities."

The new proteins were screened against a separate collection of blood samples from patients with normal and cancerous tissues. Of 23 patients with early-stage ovarian cancer, the three protein markers plus CA125 correctly identified cancer 74 percent of the time (17 of 23) as compared to 65 percent (15 of 23) with CA125 alone. Although the sample size was too small for this difference to be statistically significant, the scientists conducted further studies lowering the cutoff value for CA125 to below current standards. The new test plus CA125 as well as CA125 alone detected 83 percent (19 of 23) of the cancers. In addition, the new test plus CA125 correctly identified healthy samples 94 percent of the time (59 of 63) as compared to 52 percent (33 of 63) for CA125 alone.

To verify that the candidate markers were specific to ovarian cancer, the scientists also compared results of the protein profiles with a separate group of blood samples from 142 Johns Hopkins ovarian, breast, colon, prostate cancer patients and healthy people. Protein markers from Hopkins’ ovarian cancer samples matched those from the other two groups of blood samples. Breast, colon and prostate cancer samples exhibited levels of the three proteins closer to those of normal patients, indicating that the markers are exclusive to ovarian cancer.

The scientists will conduct further studies to map all three proteins to the genetic pathways linked to ovarian cancer development and combine the blood test with radiologic tools such as ultrasound. They also will search for more proteins to add to the current panel of markers.

Additional research participants included Robert Bast Jr. and Yinhua Yu from the M.D. Anderson Cancer Center; Jinong Li, Lori Sokoll, Alex Rai, Jason Rosenzweig, Bonnie Cameron, and Young Wang from Johns Hopkins; Andrew Berchuck from Duke University Medical Center; Carolien van Haaften-Day and Neville Hacker from The Royal Hospital for Women, Australia; Henk de Bruij and Ate van der Zee from University Hospital Groningen, the Netherlands; Ian Jacobs from Bart’s and The London, Queen Mary’s School of Medicine, United Kingdom, and Eric Fung from Ciphergen Biosystems.

Vanessa Wasta | EurekAlert!
Further information:
http://www.jhmi.edu

More articles from Life Sciences:

nachricht Fingerprint' technique spots frog populations at risk from pollution
27.03.2017 | Lancaster University

nachricht Parallel computation provides deeper insight into brain function
27.03.2017 | Okinawa Institute of Science and Technology (OIST) Graduate University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Northern oceans pumped CO2 into the atmosphere

27.03.2017 | Earth Sciences

Fingerprint' technique spots frog populations at risk from pollution

27.03.2017 | Life Sciences

Big data approach to predict protein structure

27.03.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>