Navigation Links
Nanoscale gene 'ignition switch' may help spot and treat cancer

In a proof of principal study in mice, scientists at Johns Hopkins and the Virginia Commonwealth University (VCU) have shown that a set of genetic instructions encased in a nanoparticle can be used as an "ignition switch" to rev up gene activity that aids cancer detection and treatment.

The switch, called a promoter, is a set of chemical letters that interacts with DNA to turn on gene activity. In this case, the scientists used a promoter called PEG-Prom, cloned by VCU researcher Paul Fisher, Ph.D. PEG-Prom is activated only when inside cancer cells, not in normal ones.

"With current imaging devices like CT and PET, we can tell if something is wrong in a patient, but we don't have definitive tools to distinguish cancer from inflammation or infection," says Martin Pomper, M.D., Ph.D., professor of radiology at Johns Hopkins. "It generally takes at least one month after giving patients certain cancer treatments before existing imaging tools can measure the patient's response to the therapy."

To differentiate cancer cells from normal cells, Johns Hopkins scientists connected PEG-Prom to either a gene that produces firefly luciferase, the substance that make fireflies glow, or a gene called HSV1tk, which initiates a chemical reaction with radioactive labels inside the cell that can be detected by imaging devices. Once inside a cancer cell, the PEG-Prom switch is turned on, and it activates either the luciferase or HSV1tk gene.

Then, they stuffed the PEG-Prom/gene combination into tiny spheres about 50,000 times smaller than the head of a pin and intravenously injected the nanoparticles into mice with either metastatic breast cancer or melanoma.

The findings, reported in the December 12 online edition of Nature Medicine, reveal a 30-fold difference in identifying cancer cells containing luciferase and normal cells that did not contain the substance. Similar results were observed in cancer cells filled with the radioactive labels and normal ones that were not.

"This type of imaging technique has the potential to add to existing tools with more specificity in identifying the problem," says Pomper.

Pomper says that the technique could likely be used in any cancer, and the nanoparticle and HSV1tk gene used in the current study have been tested previously in clinical studies unrelated to Pomper's work.

In addition to diagnostic and monitoring tools, the technique could be designed to deliver therapies to the heart of cancer cells. One approach, he says is to use radioactive isotopes to make cancer cells radioactive from the inside, instead of delivering radiation to the patient externally.

Still, Pomper says, such a technique would be limited to identifying tumors that are two millimeters or larger, amounting to millions of cells, because current imaging devices cannot detect anything smaller. He also says that certain doses of nanoparticles could be toxic, so his team is conducting tests to find the best nanoparticle.


Contact: Vanessa Wasta
Johns Hopkins Medical Institutions

Related medicine news :

1. Nanoscale stealth probe slides into cell walls seamlessly, say Stanford engineers
2. Cochlear Appoints Switched on Media to Develop its SEO Across the Asia Pacific Region
3. Researchers create drug to keep tumor growth switched off
4. BCS Global Launches PSVN (Public Switched Video Network), an Initiative to Provide a Framework for Inter-Connecting Business to Business Video Networks
5. Daylight-Saving Time Switch May Leave You Sleepy, U-M Physician Says
6. Researchers discover brain tumors grow-or-go switch
7. Discovery of cellular switch may provide new means of triggering cell death, treating disease
8. UBC graduate student finds a start/stop switch for retroviruses
9. Brains master switch is verified by Iowa State University researcher
10. Clue to switch of bladder cancer from locally contained to invasive found by Jefferson scientists
11. Memorys master switch
Post Your Comments:
(Date:10/13/2015)... (PRWEB) , ... October 13, 2015 , ... "My friend's ... his fists into his infected cheeks," said an inventor from Platteville, Colo. "I came ... skin problems." , He developed the UNTOUCHABLE to prevent a child from rubbing or ...
(Date:10/13/2015)... (PRWEB) , ... October 13, 2015 , ... ... of anesthesia and pain management services, today announced its partnership with WPC ... integrates data from disparate systems and organizes the data into an aggregated data ...
(Date:10/13/2015)... ... ... According to an article published October 5th by the American ... weight with a bariatric procedure are much less likely to develop endometrial cancer, which ... from 40 to 50 percent of all endometrial cancer cases are caused by obesity, ...
(Date:10/13/2015)... , ... October 13, 2015 , ... ... solutions, announced today their sponsorship of the Microsoft Dynamics AXUG, GPUG and NAVUG ... Summit, GPUG Summit and NAVUG Summit are independent user conferences designed and led ...
(Date:10/13/2015)... , ... October 13, 2015 , ... ... provider of IBM software products, introduced a new company, RightSensorâ„¢ LLC, an Internet ... data communications capability. RightSensorâ„¢ provides a fully-managed approach for customers requiring sensor ...
Breaking Medicine News(10 mins):
(Date:10/13/2015)... MUNICH , October 13, 2015 ... --> World Thrombosis Day Interactive Infographic   ... World Thrombosis Day  to promote vital ... and signs and symptoms. Thrombosis is the formation ... (venous thrombosis) - resulting in venous thromboembolism (VTE) ...
(Date:10/13/2015)... PARK, Calif. , Oct. 13, 2015 /PRNewswire/ ... an agreement with the UK-based Cell Therapy Catapult ... for AST-VAC2, Asterias, allogeneic dendritic cell immunotherapy. Under ... and scale manufacturing processes for AST-VAC2 to support ... --> --> ...
(Date:10/12/2015)... -- Given the intricacy of the anatomy and ... an ophthalmic drug effectively to a specific ocular site. Several ... delivery. These include dilution of a drug by tears, clearance ... drug permeation issues with respect to the cornea, sclera and ... is lost due to the aforementioned barriers. --> ...
Breaking Medicine Technology: