Navigation Links
Nanoscale gene 'ignition switch' may help spot and treat cancer
Date:12/15/2010

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
wasta@jhmi.edu
410-955-1287
Johns Hopkins Medical Institutions
Source:Eurekalert

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:
*Name:
*Comment:
*Email:
(Date:6/23/2017)... ... June 23, 2017 , ... Radabaugh & Associates, a locally ... business owners in North Central West Virginia, is embarking on a cooperative charity ... residents in the region. , The Stepping Stones organization offers a series of ...
(Date:6/22/2017)... ... 2017 , ... Plastic Surgery Associates is proud to report that founding surgeon, ... research and information firm, Castle Connolly, releases their list of the most notable and ... 3rd time that Dr. Canales has been recognized by Castle Connolly. , ...
(Date:6/22/2017)... ... June 22, 2017 , ... ... from the American Heart Association (AHA) to launch a Rheumatic Heart Disease Center, ... prevention and diagnosis of rheumatic heart disease (RHD) in high-risk, financially disadvantaged countries ...
(Date:6/22/2017)... , ... June 22, 2017 , ... ... announced today that it has received certification for ANSI/ASIS PSC.1-2012. The company’s work ... in environments where the rule of law has been degraded. The PSC.1 standard ...
(Date:6/20/2017)... ... June 20, 2017 , ... TwelveStone Health Partners, ... a Nashville-based private equity firm, has invested $3.35 million in the company. ... and Claritas Capital offers the smart money, speed to market and accountability we ...
Breaking Medicine News(10 mins):
(Date:6/7/2017)... -- Endo International plc (NASDAQ: ENDP ) ... Joseph R. Goodwin , U.S. District Court Judge for ... , entered a case management order in MDL 2325, ... Litigation (the "MDL") that includes a provision requiring plaintiffs ... on specific causation within one hundred twenty (120) days ...
(Date:6/3/2017)... 2017  Eli Lilly and Company (NYSE: ... the Phase 3 MONARCH 2 study showed that ... in combination with fulvestrant, significantly improved progression-free survival ... women with hormone-receptor-positive (HR+), human epidermal growth factor ... relapsed or progressed after endocrine therapy (median PFS, ...
(Date:5/30/2017)... AVIV, Israel , May 30, 2017 ... stage pharmaceutical Company specializing in the development of ... will present a company overview at three upcoming ... The 7th Annual LD Micro Invitational: ... Date:                     ...
Breaking Medicine Technology: