Monday, February 1, 2016

Cells talk to their neighbors before making a move

To decide whether and where to move in the body, cells must read chemical signals in their environment. Individual cells do not act alone during this process, two new studies on mouse mammary tissue show. Instead, the cells make decisions collectively after exchanging information about the chemical messages they are receiving.


"Cells talk to nearby cells and compare notes before they make a move," says Ilya Nemenman, a theoretical biophysicist at Emory University and a co-author of both studies, published by the Proceedings of the National Academy of Sciences (PNAS). The co-authors also include scientists from Johns Hopkins, Yale and Purdue.
The researchers discovered that the cell communication process works similarly to a message relay in the telephone game. "Each cell only talks to its neighbor," Nemenman explains. "A cell in position one only talks to a cell in position two. So position one needs to communicate with position two in order to get information from the cell in position three."
And like the telephone game -- where a line of people whisper a message to the person next to them -- the original message starts to become distorted as it travels down the line.
The researchers found that, for the cells in their experiments, the message begins to get garbled after passing through about four cells, by a factor of about three.
"We built a mathematical model for this linear relay of cellular information and derived a formula for its best possible accuracy," Nemenman says. "Directed cell migration is important in processes from cancer to the development of organs and tissues. Other researchers can apply our model beyond the mouse mammary gland and analyze similar phenomena in a wide variety of healthy and diseased systems."
Since at least the 1970s, and pivotal work by Howard Berg and Ed Purcell, scientists have been trying to understand in detail how cells decide to take an action based on chemical cues.
Every cell in a body has the same genome but they can do different things and go in different directions because they measure different chemical signals in their environment. Those chemical signals are made up of molecules that randomly move around.
"Cells can sense not just the precise concentration of a chemical signal, but concentration differences," Nemenman says. "That's very important because in order to know which direction to move, a cell has to know in which direction the concentration of the chemical signal is higher. Cells sense this gradient and it gives them a reference for the direction in which to move and grow."
Berg and Purcell understood the best possible margin of error -- the detection limit -- for such gradient sensing. During the subsequent 30 years, researchers have established that many different cells, in many different organisms, work at this detection limit. Living cells can sense chemicals better than any humanmade device.
It was not known, however, that cells can sense signals and make movement decisions collectively.
"Previous research has typically focused on cultured cells," Nemenman says. "And when you culture cells, the first thing to go away is cell-to-cell interaction. The cells are no longer a functioning tissue, but a culture of individual cells, so it's difficult to study many collective effects."
The first PNAS paper drew from three-dimensional micro-fluidic techniques from the Yale University lab of Andre Levchenko, a biomedical engineer who studies how cells navigate; research on mouse mammary tissue at the Johns Hopkins lab of Andrew Ewald, a biologist focused on the cellular mechanisms of cancer; and the quantification methods of Nemenman, who studies the physics of biological systems, and Andrew Mugler, a former post-doctoral fellow in Nemenman's lab at Emory who now has his own research group at Purdue.
The 3D micro fluidics allowed the researchers to experiment with functional organoids, or clumps of cells. The method does not disrupt the interaction of the cells.
The results showed that epidermal growth factor, or EGF, is the signal that these cells track, and that the cells were not making decisions about which way to move as individuals, but collectively.
"The clumps of cells, working collectively, could detect insanely small differences in concentration gradients -- such as 498 molecules of EGF versus 502 molecules -- on different sides of one cell," Nemenman says. "That accuracy is way better than the best possible margin of error determined by Berg and Purcell of about plus or minus 20. Even at these small concentration gradients, the organoids start reshaping and moving toward the higher concentration. These cells are not just optimal gradient detectors. They seem super optimal, defying the laws of nature."
Collective cell communication boosts their detection accuracy, turning a line of about four cells into a single, super-accurate measurement unit.
In the second PNAS paper, Nemenman, Mugler and Levchenko looked at the limits to the cells' precision of collective gradient sensing not just spatially, but over time.
"We hypothesized that if the cells kept on communicating with one another over hours or days, and kept on accumulating information, that might expand the accuracy further than four cells across," Nemenman says. "Surprisingly, however, this was not the case. We found that there is always a limit of how far information can travel without being garbled in these cellular systems."
Together, the two papers offer a detailed model for collective cellular gradient sensing, verified by experiments in mouse mammary organoids. The collective model expands the classic Berg-Purcell results for the best accuracy of an individual cell, which stood for almost forty years. The new formula quantifies the additional advantages and limitations on the accuracy coming from the cells working collectively.
"Our findings are not just intellectually important. They provide new ways to study many normal and abnormal developmental processes," Nemenman says.

Story Source:
The above post is reprinted from materials provided by Emory Health Sciences. The original item was written by Carol Clark. Note: Materials may be edited for content and length.

Monday, January 25, 2016

Scared But Not Alone

       Just this weekend I had the opportunity to talk with people about healthcare.  The more people I talk to the more I understand how many people have had to deal with the scare that I have had.  When my husband and I got my diagnosis of breast cancer we really didn't know what to do, where to start.  I'm afraid that happens to more often than not.  We had discussions of what would we sell first because we didn't know how much our insurance would cover or what it meant.  After the initial shock we were one of the lucky ones.  With good doctors and a supportive and comprehensive group of people we made it through.  They were there to support us and help us with the financial end of it as well.  Even if this is not the last time I may deal with this terrible disease I know they are there to support me.  For those who don't have that support, and I know of some, where can they turn.  This may be a site that you might want to recommend to those you know who are just beginning their journey.  It is the Cancer Care site.

     It is a fountain of information not only for those with cancer but also for those who are charged with their care.  Surprising enough the journey through cancer and treatment is not only traveled by the one diagnosed, but also by the ones that are the closest to them.  This site has a spot for them as well.  And last but not least, once the treatment journey is over the fight is not.  Those that are survivors, and I mean the caregivers as well, still need support.  They have a spot for you as well.

For those who have more questions than answers, they are only a click away.



A cancer diagnosis turns a person’s world upside down--emotionally, physically and financially. CancerCare® can help.
We provide telephone, online and face-to-face counselingsupport groupseducationpublications and financial and co-payment assistance. Professional oncology social workers offer personalized care, and all of our services are free of charge.
Explore our website to learn more, and call us at 800-813-HOPE (4673).

Tuesday, January 19, 2016

Attitude

Always make it possitive. It makes all the difference.


Monday, January 18, 2016

Possible Early Detection for Pancreatic Cancer

Over 85 percent of Pancriatic Cancers are diagnosed too late leaving the person with just a 2 percent chance of survivial.  This boy has come up with an easy, inexpensive, and less envasive way to detect this dreaded cancer.  Click on this link to find out more:

Sunday, January 17, 2016

Why Curing Cancer Is Not a ‘Moonshot’

(Taken from: http://time.com/4178742/cancer-moonshot-obama/)
Here are some things that have been compared to moonshots: Google Books, nuclear fusion, Google Glass, artificial brains, drone delivery, getting from New York to London in one hour, a really big home run.
Here are some things that actually are moonshots: going to the moon.
Of all of the metaphors that have gotten shiny at the elbows, it’s the beleaguered “moonshot” that may be the worst. President Obama rolled it out again during his final State of the Union address when, expressing a desire to cure cancer once and for all, he called for a moonshot to get the job done.
The audience applauded as audiences always do at moonshots, and it’s hard not to. The term evokes one of America’s finest and boldest moments, when the Soviet Union beat us into space with Sputnik, the first artificial satellite, and we responded with men on the moon less than 12 years later. But the problem with using that real moonshot to call for metaphorical moonshots is that it misunderstands both the stakes and the difficulty of actually accomplishing what it is you’re trying to do—making hard things seem easier than they are.
Getting to the moon was undeniably an extraordinary thing. But we were further along when we began than most people realize. We knew how to build rockets—indeed we had already built plenty of them, though we called them missiles and put warheads instead of astronauts at the top. We similarly understood the physics of orbital and translunar flight; we just had to master them.
More important was the clarity and singularity of the stated goal, announced by President Kennedy in 1961: putting at least one man on the moon and bringing him home before 1970. Period. The commitment to that goal would have to be maintained over three presidencies and seven different congresses, which was perhaps the hardest thing of all. But knowing it would take just a single set of lunar footprints and the job would be done helped keep everyone focused.
Now consider cancer, or, more accurately, cancers—plural. Scientists have long known cancer isn’t one disease—it’s perhaps 100 or more, with the number growing as different types and sub-types are better understood. Making things worse, there will be perhaps 1.6 million Americans diagnosed with cancer in the U.S. alone this year, and each of those cases will be in some ways unique. That’s part of the reason two people with the same kind of cancer diagnosed at the same stage and receiving the same treatment can have radically different outcomes.
Actually “curing cancer”—in the larger global sense of simply wiping it out—would require personalized care, designed around every single patient with any single type of the disease. And in order to administer that kind of tailored care to every single person diagnosed with cancer, a whole lot more research is going to be needed. That may not be an unattainable goal—but it’s a devilishly complicated one.
With the “war on cancer,” declared by President Nixon in 1971, the imagery was different—if still seductive—but the idea was the same. It took us less than four years to go from the humiliation of Pearl Harbor to the utter defeat of the Axis powers, didn’t it? Why couldn’t the same commitment of manpower and treasure do something similar with cancer? But cancer—far too nimble, far too complex—didn’t play along then, and it won’t now.
It’s not as if all disease is impervious to a moonshot-type effort. The National Foundation for Infantile Paralysis was the NASA of the fight for a polio vaccine. That war was won, because polio is only one disease—albeit caused by three strains of virus—and on April 12, 1955 when the Foundation announced that the Salk vaccine was safe and effective, victory could be declared. The success has been even more complete against smallpox, which was officially eradicated in 1980 and exists today only in small viral samples in high-security labs.
Moonshots can work for other challenges too. Developing a clean-energy grid? Perfecting and mass-producing the driverless car? Pushing high school graduation rates above, say, 95 percent? Sure.
There is nothing wrong with calling for a national commitment to do something that’s very hard and, often, very expensive; indeed it’s a form of Presidential malpractice to see a grave problem and not do that. Obama—and Nixon before him—deserve credit for throwing down that challenge flag against cancer. But this moon is actually many moons. Expecting a single, final victory will only make us fail to notice the smaller, more incremental ones when they come.

Thursday, October 29, 2015

Get Informed!

Cancer Treatment and Survivorship Facts and Figures

Cancer Treatment & Survivorship Facts & Figures

The number of Americans with a history of cancer is growing due to the aging and growth of the population, as well as improving survival rates. This comprehensive survivorship report, a collaboration between two of the Society’s Intramural Research Programs -- Surveillance & Health Services Research and Behavioral Research – and the National Cancer Institute, provides current and projected cancer prevalence estimates for the United States, as well as data from the National Cancer Data Base on treatment patterns, and information on the common effects of cancer and its treatment. This Facts & Figures title is the newest addition to the series.