Pathology and social interactions: Safety in numbers

September 03, 2018

What if social behavior affected the progression of even noncontagious diseases? This is precisely what has been demonstrated by French CNRS teams,(1) with support from the French National Research Institute for Sustainable Development (IRD), Paris-Sud University, the University of Montpellier, the French Alternative Energies and Atomic Energy Commission (CEA), and colleagues from Spain and Australia. Using a fly model of intestinal cancer, the researchers have shown that disease progression is impacted both by social isolation--which has a negative effect--and the composition of the social group with which individuals associate. Their findings are published in Nature Communications (September 3, 2018).

For many animals, humans included, social behavior can play a critical role in the survival of individuals. The effect that interactions between individuals can have on the spread of communicable diseases is well known. But is there any connection between social interactions and the progression, within sick individuals, of noncommunicable diseases like cancers? To address this question, the scientists chose the fruit fly Drosophila melanogaster as their research model. Control of the social environment and experimental induction of disease (an intestinal cancer in this case) are both easily achieved when working with drosophilas. The team sought to determine whether the social environment of diseased individuals altered the speed of tumor progression and if these flies could choose their social environment to slow this progression.

They observed that disease progression in sick flies was faster in social isolation than when interacting with other flies. Even more surprisingly, the very structure of a diseased fly's social group could affect the progression of its illness. When a sick fly is in the company of healthy ones, its tumor spreads more quickly than when interacting with other sick individuals. Detailed analyses of interactions between flies, monitored through video, suggest that sick flies interact less with healthy ones in their presence--effectively exhibiting a sort of isolation in the midst of the healthy crowd.

It is interesting to note that, when given the choice between a sick or healthy group, a sick fly will choose to join other sick flies--at least during the early stages of illness. Once the tumor is in an advanced state, the fly no longer shows any preference. The behavior of healthy flies is different. Though they make no distinction between healthy flies and sick flies at an early stage of disease, they will avoid sick flies with more advanced tumors and prefer the company of other healthy flies. The exact reasons for such avoidance are still poorly understood and currently under study. It may reflect a nonspecific response to the risks posed by diseases in general--such as contagion, compromised reproductive potential, and greater vulnerability to predators.

Though these findings cannot yet be extrapolated to humans, they suggest that social environment plays a substantial, even major, role in the development of a disease like cancer.
-end-
(1) The CNRS research units involved were EGCE (CNRS / IRD / Paris-Sud University), the Institute for Integrative Biology of the Cell (CNRS / Paris-Sud University / CEA), and MIVEGEC (CNRS / IRD / University of Montpellier).

CNRS

Related Cancer Articles from Brightsurf:

New blood cancer treatment works by selectively interfering with cancer cell signalling
University of Alberta scientists have identified the mechanism of action behind a new type of precision cancer drug for blood cancers that is set for human trials, according to research published in Nature Communications.

UCI researchers uncover cancer cell vulnerabilities; may lead to better cancer therapies
A new University of California, Irvine-led study reveals a protein responsible for genetic changes resulting in a variety of cancers, may also be the key to more effective, targeted cancer therapy.

Breast cancer treatment costs highest among young women with metastic cancer
In a fight for their lives, young women, age 18-44, spend double the amount of older women to survive metastatic breast cancer, according to a large statewide study by the University of North Carolina at Chapel Hill.

Cancer mortality continues steady decline, driven by progress against lung cancer
The cancer death rate declined by 29% from 1991 to 2017, including a 2.2% drop from 2016 to 2017, the largest single-year drop in cancer mortality ever reported.

Stress in cervical cancer patients associated with higher risk of cancer-specific mortality
Psychological stress was associated with a higher risk of cancer-specific mortality in women diagnosed with cervical cancer.

Cancer-sniffing dogs 97% accurate in identifying lung cancer, according to study in JAOA
The next step will be to further fractionate the samples based on chemical and physical properties, presenting them back to the dogs until the specific biomarkers for each cancer are identified.

Moffitt Cancer Center researchers identify one way T cell function may fail in cancer
Moffitt Cancer Center researchers have discovered a mechanism by which one type of immune cell, CD8+ T cells, can become dysfunctional, impeding its ability to seek and kill cancer cells.

More cancer survivors, fewer cancer specialists point to challenge in meeting care needs
An aging population, a growing number of cancer survivors, and a projected shortage of cancer care providers will result in a challenge in delivering the care for cancer survivors in the United States if systemic changes are not made.

New cancer vaccine platform a potential tool for efficacious targeted cancer therapy
Researchers at the University of Helsinki have discovered a solution in the form of a cancer vaccine platform for improving the efficacy of oncolytic viruses used in cancer treatment.

American Cancer Society outlines blueprint for cancer control in the 21st century
The American Cancer Society is outlining its vision for cancer control in the decades ahead in a series of articles that forms the basis of a national cancer control plan.

Read More: Cancer News and Cancer Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.