Featured Research

from universities, journals, and other organizations

Lab-on-a-chip Homes In On How Cancer Cells Break Free

Date:
March 25, 2009
Source:
Johns Hopkins University
Summary:
Engineers have invented a method to help figure out how cancer cells break free from neighboring tissue, an "escape" that can spread the disease to other parts of the body.

Johns Hopkins Cell Detachment Research with Lab-on-a-Chip At left, the illustration shows adhesive complex formed between cell membrane-bound protein (integrin in gray) with peptide (RGD in red) tethered by thiol molecules (blue) to gold electrode (yellow) on glass slide (green). At right, electrochemical release of tethered peptide from the gold electrode results in local release of the RGD-integrin complex.
Credit: Diagram by Peter Searson

Johns Hopkins engineers have invented a method that could be used to help figure out how cancer cells break free from neighboring tissue, an "escape" that can spread the disease to other parts of the body. The new lab-on-a-chip, described in the March issue of the journal Nature Methods, could lead to better cancer therapies.

"Studying cell detachment at the subcellular level is critical to understanding the way cancer cells metastasize," says principal investigator Peter Searson, Reynolds Professor of Materials Science and Engineering. "Development of scientific methods to study cell detachment may guide us to prevent, limit or slow down the deadly spreading of cancer cells."

His team's research focuses on a missing puzzle piece in the common but unfortunate events that can occur in cancer patients. For example, cancer that starts in the breast sometimes spreads to the lungs.

That's because tumor cells detach and travel through the bloodstream to settle in other tissues. Scientists have learned much about how cancer cells attach to these surfaces, but they know little about how these insidious cells detach because no one had created a simple way to study the process.

Searson and two other scientists from Johns Hopkins' Whiting School of Engineering have solved this problem with a lab-on-a-chip device that can help researchers study cell detachment. With this device, they hope to discover exactly how cancer cells spread.

The lab-on-a-chip device consists of an array of gold lines on a glass slide. Molecules promoting the formation of cell attachments are tethered to the gold lines like balloons tied to string. A cell is placed on the chip, atop these molecules. The cell spreads across several of the gold lines, forming attachments to the surface of the chip with help from the molecules.

Then, the tethered molecules are released from one of the lines by a chemical reaction, specifically by "electrochemical reduction," Searson explains. Where these molecules are detached, that portion of the cell loses its grip on the surface of the chip. This segment of the cell pauses for a moment and then contracts forcefully toward its other end, which is still attached to the chip. The researchers were able to film this "tail snap" under a microscope.

"It's very dramatic," says Denis Wirtz, a Johns Hopkins professor of chemical and biomolecular engineering and co-author of the Nature Methods paper. "The cell stretches way, way out across the chip and then, on command, the tail snaps toward the body of the cell."

Cells survive this programmed-release process and can be tested again and again, the researchers said.

Bridget Wildt, a materials science and engineering doctoral student in Searson's lab, used the device to perform and record movies of the live-cell experiments. Wildt tested cells from the connective tissue of mice during these experiments, but the team plans to try other types of cells in the future.

"In the movies, you can see that the cell doesn't move immediately after the chemical reaction is triggered. We refer to this phenomenon as the induction time of the cell," Wildt says. "After this induction time, the cell then snaps back and contracts. We analyze the rate of the cell's contraction and then compare this information to separate cells released under different conditions using chemicals called inhibitors. From these results we are beginning to understand the processes that regulate cell detachment at the molecular level."

The researchers have speculated that the induction time for cancer cells, as compared to noncancerous cells, would be shorter because cancer cells are more pliable. In the near future, Wildt says, they plan to test this hypothesis in experiments with cancer cells. If this assumption proves correct, it may give them a tool to differentiate between cancerous and noncancerous cells.

Searson is director and Wirtz is associate director of the Johns Hopkins Institute for NanoBioTechnology. Their work was supported by grants from the U.S. National Institutes of Health, National Science Foundation and the Howard Hughes Medical Institution. Wildt's participation in the research was funded by the Achievement Rewards for College Scientists Foundation.

The new study — "Programmed subcellular release for studying the dynamics of cell detachment," Bridget Wildt, Denis Wirtz, and Peter C. Searson — can be viewed online at: http://www.nature.com/nmeth/journal/v6/n3/full/ nmeth.1299.html.


Story Source:

The above story is based on materials provided by Johns Hopkins University. Note: Materials may be edited for content and length.


Cite This Page:

Johns Hopkins University. "Lab-on-a-chip Homes In On How Cancer Cells Break Free." ScienceDaily. ScienceDaily, 25 March 2009. <www.sciencedaily.com/releases/2009/03/090318122004.htm>.
Johns Hopkins University. (2009, March 25). Lab-on-a-chip Homes In On How Cancer Cells Break Free. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2009/03/090318122004.htm
Johns Hopkins University. "Lab-on-a-chip Homes In On How Cancer Cells Break Free." ScienceDaily. www.sciencedaily.com/releases/2009/03/090318122004.htm (accessed July 24, 2014).

Share This




More Health & Medicine News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com
Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Newsy (July 24, 2014) Sheik Umar Khan has treated many of the people infected in the Ebola outbreak, and now he's become one of them. Video provided by Newsy
Powered by NewsLook.com
Condemned Man's US Execution Takes Nearly Two Hours

Condemned Man's US Execution Takes Nearly Two Hours

AFP (July 24, 2014) America's death penalty debate raged Thursday after it took nearly two hours for Arizona to execute a prisoner who lost a Supreme Court battle challenging the experimental lethal drug cocktail. Duration: 00:55 Video provided by AFP
Powered by NewsLook.com
China's Ageing Millions Look Forward to Bleak Future

China's Ageing Millions Look Forward to Bleak Future

AFP (July 24, 2014) China's elderly population is expanding so quickly that children struggle to look after them, pushing them to do something unexpected in Chinese society- move their parents into a nursing home. Duration: 02:07 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile: iPhone Android Web
          Follow: Facebook Twitter Google+
          Subscribe: RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins