Navigation Links
Scientists Spot Genetic 'Fingerprints' of Individual Cancers
Date:2/18/2010

Discovery could help doctors track course of disease, treatment response

THURSDAY, Feb. 18 (HealthDay News) -- Researchers have found a way to analyze the "fingerprint" of a cancer, and then use that fingerprint to track the trajectory of that particular tumor in that particular person.

"[This technique] will allow us to measure the amount of cancer in any clinical specimen as soon as the cancer is identified by biopsy," said study co-author Dr. Luis Diaz, an assistant professor of oncology at Johns Hopkins University. "This can then be scanned for gene rearrangements, which will then be used as a template to track that particular cancer."

Diaz is one of a group of researchers from the Ludwig Center for Cancer Genetics and Therapeutics and the Howard Hughes Medical Institute at Johns Hopkins Kimmel Cancer Center that report on the discovery in the Feb. 24 issue of Science Translational Medicine.

This latest finding brings scientists one step closer to personalized cancer treatments, experts say.

"These researchers have determined the entire genomic sequence of several breast and colon cancers with great precision," said Katrina L. Kelner, the journal's editor. "They have been able to identify small genomic rearrangements unique to that tumor and, by following them over time, have been able to follow the course of the disease."

One of the biggest challenges in cancer treatment is being able to see what the cancer is doing after surgery, chemo or radiation and, in so doing, help guide treatment decisions.

"Some cancers can be monitored by CT scans or other imaging modalities, and a few have biomarkers you can follow in the blood but, to date, no universal method of accurate surveillance exists," Diaz stated.

Almost all human cancers, however, exhibit "rearrangement" of their chromosomes.

"Rearrangements are the most dramatic form of genetic changes that can occur," study co-author Dr. Victor Velculescu explained, likening these arrangements to the chapters of a book being out of order. This type of mistake is much easier to recognize than a mere typo on one page.

But traditional genome-sequencing technology simply could not read to this level.

Currently available next-generation sequencing methods, by contrast, allow the sequencing of hundreds of millions of very short sequences in parallel, Velculescu explained.

For this study, the researchers used a new, proprietary approach called Personalized Analysis of Rearranged Ends (PARE) to analyze four colorectal and two breast cancer tumors.

First, they analyzed the tumor specimen and identified the rearrangements, then tested two blood samples to verify that the DNA had been shed into the blood, sort of like a tumor's trail of bread crumbs.

"Every cancer analyzed had these rearrangements and every rearrangement was unique and occurred in a different location of genome," said Velculescu. "No two patients had the same exact rearrangements and the rearrangements occurred only in tumor samples, not in normal tissue," he noted.

"This is a potentially highly sensitive and specific tumor marker," Velculescu added. Levels of the biomarkers also corresponded with the waxing and waning of the tumor.

"When the tumor progresses, the relative amount of the rearrangement increases in the blood and goes down after chemotherapy," Diaz said. "It tracks very nicely with the clinical history of the tumor."

The method would not be used for cancer screening and more research needs to be done to make sure PARE doesn't detect low-level tumors that don't actually need any treatment.

Although this approach is currently expensive (about $5,000 versus $1,500 for a CT scan), the authors anticipate that the cost will come down dramatically in the near future, making PARE more cost-effective than a CT scan.

Under the terms of a licensing agreement, three of the study authors, including Velculescu, are entitled to a share of royalties on sales of products related to these findings.

More information

The American Cancer Society has more on personalized cancer care.



SOURCES: Feb. 18, 2010, teleconference with: Katrina L. Kelner, Ph.D., editor, Science Translational Medicine; Victor Velculescu, M.D., Ph.D., associate professor, oncology, and co-director, cancer biology program, Johns Hopkins Kimmel Cancer Center, Baltimore, and Luis Diaz, M.D., assistant professor, oncology, Johns Hopkins University; Feb. 24, 2010, Science Translational Medicine


'/>"/>
Copyright©2010 ScoutNews,LLC.
All rights reserved

Related medicine news :

1. Johns Hopkins scientists develop personalized blood tests for cancer using whole genome sequencing
2. Two UCSF Scientists to Receive Prestigious Dementia Research Honor
3. Neuroscientists reveal new links that regulate brain electrical activity
4. Scientists find donut-shaped structure of enzyme involved in energy metabolism
5. Scientists Discover Molecular Pathway for Organ Tissue Regeneration and Repair
6. Prevention Is Key Research Goal for Premature Babies, Scientists Say
7. Scientists Discover How HIV Is Transmitted Between Men
8. Scientists Pinpoint Area of Brain That Fears Losing Money
9. Scientists Spot Genes Tied to Aging
10. UM School of Medicine scientists find new malaria vaccine is safe and promotes immune response in children
11. Scientists ID a protein that splices and dices genes
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:7/21/2017)... ... July 21, 2017 , ... The Wettstein Agencies, ... communities in the greater Denver region, is announcing a charity drive to help ... rare kind of epilepsy. , Until a few months ago, Dominik was a ...
(Date:7/21/2017)... Helena, AL (PRWEB) , ... July 21, 2017 ... ... that offers insurance assistance and financial planning services to communities in the greater ... that promises to provide resources to underprivileged young people in the region. , ...
(Date:7/21/2017)... ... July 21, 2017 , ... ... Theater of Witness , was awarded a $300,000 grant from The Pew ... fosters empathy, comfort with ambiguity and the recognition of one’s own limits among ...
(Date:7/21/2017)... ... ... The Margarian Law Firm has filed a class action lawsuit ... containing no ginger. Dr. Pepper produces the “Canada Dry” brand of ginger ale products. ... Dry Ginger Ale claims on its bottle that it is made from real ginger. ...
(Date:7/21/2017)... ... July 21, 2017 , ... MedMatchPlus+ has launched a ... acceptance to a residency in a United States hospital. Being accepted into a ... , According to data released by the ECFMG®, every year, 50 percent of ...
Breaking Medicine News(10 mins):
(Date:7/14/2017)... 13, 2017 It should come as no surprise ... is in the midst of a crippling opioid epidemic. According ... the number of overdose deaths from opiate-based medications has quadrupled, ... a million dead from 2001 to 2015". During this time, ... has similarly quadrupled, drawing a compelling link between prescription and ...
(Date:7/12/2017)...  Eli Lilly and Company (NYSE: LLY ) ... resolve pending patent litigation in the U.S. District Court for ... the Cialis ® (tadalafil) unit dose patent. This patent ... part of the agreement, Cialis exclusivity is now expected to ... "The unit dose patent for Cialis is valid and infringed ...
(Date:7/11/2017)...  Dr. Echenberg, founder of Echenberg Institute, is announcing a new safe ... from painful intercourse and other painful pelvic pain conditions such as pelvic ... ... ... Florida -based start-up company, VuVatech LLC, fills a void in the ...
Breaking Medicine Technology: