Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cancer Detection Method Overcomes Problem of Samples with Few Cells

26.07.2004


Finding cancer in a tiny drop of body fluid containing relatively few cells now may be possible with a new method of analyzing multiple genes in small samples of DNA, the cellular building blocks of our genetic code. The molecular test may be especially helpful in detecting cancer cells in breast fluid.



Preliminary tests of the new method, which can detect cancer in a sample with as few as 50 cells, were conducted on a small number of breast tissue samples and are reported in the July 1 issue of Cancer Research. "Our goal is to add a molecular solution to problems in cancer diagnosis where the sample is not adequate or microscopic evaluation of cells is unclear," says Sara Sukumar, Ph.D., the Barbara B. Rubenstein Professor of Oncology at the Johns Hopkins Kimmel Cancer Center. "If additional studies prove the feasibility of this test, it will provide molecular clues to cellular pathology and mammography findings that may help to decide whether cancer is present."

The test, called quantitative multiplex methylation-specific PCR or QM-MSP, works by looking for unusually high levels of molecules embedded by a process called methylation within critical regions of DNA. In this process, small methyl groups regulate DNA’s message-manufacturing process by attaching to the "on" switch of genes. Abnormal levels of methylation improperly turn the gene switch off, which ultimately leads to the loss of critical proteins found in normal cells. This adds to the cascade of genetic events leading to cancer.


"Until now, accurate levels of methylation in many genes at the same time was impossible without repeated tests, and with a small sample, we didn’t have enough DNA to perform all those tests," says Mary Jo Fackler, Ph.D., research associate at the Kimmel Cancer Center and first author of the study. "Now, we’ve taken two existing types of MSP tests and put them together, which minimizes the amount of sample needed."

QM-MSP determines the percentage of methylation present in each of four to five breast cancer genes. The percentages are added together for a cumulative score, which is compared to a threshold value. Levels above the threshold indicate the potential presence of cancer cells and below threshold suggests that the samples are normal.

In the first set of experiments, the Hopkins scientists tested QM-MSP on tissue samples using a panel of genes whose abnormal methylation patterns are known to be associated with breast cancer. The test detected cancer in 84 percent (16 of 19) of breast tumor samples, and found no cancer in 89 percent (eight of nine) normal tissues.

Next, the team tested QM-MSP on breast duct fluid samples obtained through a process called ductal lavage, a saline wash via a catheter threaded through the nipple. Of seven patients at high-risk for breast cancer and no known cancer present, six had no detectable levels of abnormal methylation in their breast cells, and one woman had low levels of abnormal methylation in one gene. QM-MSP detected cancer in two out of four breast cancer patients, which, the investigators say, indicates that this assessment tool holds some promise and is being evaluated in larger studies at Johns Hopkins.

According to the Hopkins team, the QM-MSP technique could be applied to the analysis of methylation in other cancers, such as oral lavage in head and neck, or sputum for lung cancer in which tissue samples are typically small.

This research was funded by the National Cancer Institute, Avon Foundation, Susan G. Komen Foundation, and the Department of Defense.

Other scientists participating in this research are Pedram Argani, M.D., Julie Lange, M.D., Elizabeth Garrett, Ph.D., Megan McVeigh, Jyoti Mehrotra, Ph.D., Marissa A. Blum, and Amanda Lapides from Johns Hopkins University School of Medicine.

| newswise
Further information:
http://www.hopkinsmedicine.org

More articles from Health and Medicine:

nachricht Routing gene therapy directly into the brain
07.12.2017 | Boston Children's Hospital

nachricht New Hope for Cancer Therapies: Targeted Monitoring may help Improve Tumor Treatment
01.12.2017 | Berliner Institut für Gesundheitsforschung / Berlin Institute of Health (BIH)

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: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Long-lived storage of a photonic qubit for worldwide teleportation

12.12.2017 | Physics and Astronomy

Multi-year submarine-canyon study challenges textbook theories about turbidity currents

12.12.2017 | Earth Sciences

Electromagnetic water cloak eliminates drag and wake

12.12.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>