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 Modern genetic sequencing tools give clearer picture of how corals are related
17.08.2017 | University of Washington

nachricht The irresistible fragrance of dying vinegar flies
16.08.2017 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Gold shines through properties of nano biosensors

17.08.2017 | Physics and Astronomy

Greenland ice flow likely to speed up: New data assert glaciers move over sediment, which gets more slippery as it gets wetter

17.08.2017 | Earth Sciences

Mars 2020 mission to use smart methods to seek signs of past life

17.08.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>