Know more

About cookies

What is a "cookie"?

A "cookie" is a piece of information, usually small and identified by a name, which may be sent to your browser by a website you are visiting. Your web browser will store it for a period of time, and send it back to the web server each time you log on again.

Different types of cookies are placed on the sites:

  • Cookies strictly necessary for the proper functioning of the site
  • Cookies deposited by third party sites to improve the interactivity of the site, to collect statistics

Learn more about cookies and how they work

The different types of cookies used on this site

Cookies strictly necessary for the site to function

These cookies allow the main services of the site to function optimally. You can technically block them using your browser settings but your experience on the site may be degraded.

Furthermore, you have the possibility of opposing the use of audience measurement tracers strictly necessary for the functioning and current administration of the website in the cookie management window accessible via the link located in the footer of the site.

Technical cookies

Name of the cookie

Purpose

Shelf life

CAS and PHP session cookies

Login credentials, session security

Session

Tarteaucitron

Saving your cookie consent choices

12 months

Audience measurement cookies (AT Internet)

Name of the cookie

Purpose

Shelf life

atid

Trace the visitor's route in order to establish visit statistics.

13 months

atuserid

Store the anonymous ID of the visitor who starts the first time he visits the site

13 months

atidvisitor

Identify the numbers (unique identifiers of a site) seen by the visitor and store the visitor's identifiers.

13 months

About the AT Internet audience measurement tool :

AT Internet's audience measurement tool Analytics is deployed on this site in order to obtain information on visitors' navigation and to improve its use.

The French data protection authority (CNIL) has granted an exemption to AT Internet's Web Analytics cookie. This tool is thus exempt from the collection of the Internet user's consent with regard to the deposit of analytics cookies. However, you can refuse the deposit of these cookies via the cookie management panel.

Good to know:

  • The data collected are not cross-checked with other processing operations
  • The deposited cookie is only used to produce anonymous statistics
  • The cookie does not allow the user's navigation on other sites to be tracked.

Third party cookies to improve the interactivity of the site

This site relies on certain services provided by third parties which allow :

  • to offer interactive content;
  • improve usability and facilitate the sharing of content on social networks;
  • view videos and animated presentations directly on our website;
  • protect form entries from robots;
  • monitor the performance of the site.

These third parties will collect and use your browsing data for their own purposes.

How to accept or reject cookies

When you start browsing an eZpublish site, the appearance of the "cookies" banner allows you to accept or refuse all the cookies we use. This banner will be displayed as long as you have not made a choice, even if you are browsing on another page of the site.

You can change your choices at any time by clicking on the "Cookie Management" link.

You can manage these cookies in your browser. Here are the procedures to follow: Firefox; Chrome; Explorer; Safari; Opera

For more information about the cookies we use, you can contact INRAE's Data Protection Officer by email at cil-dpo@inrae.fr or by post at :

INRAE

24, chemin de Borde Rouge -Auzeville - CS52627 31326 Castanet Tolosan cedex - France

Last update: May 2021

Menu Logo Principal AgroParisTech Université Paris-Saclay UVSQ ANSES CNRS ENVA

Home page

Breast Cancer: a chronic disturbance of the circadien rythme increases the dissemination of cancer cells

24 June 2020

@Pixabay
Breast cancer is the most wide-spread cancer in the world and one of the main causes of death in women. A study implicating scientists from the Paris-Saclay University, INSERM and INRAE just established a link between night shift working and an increased risk of cancer, suggesting that disruption of circadian rythms could make tumors more agressive. This study was published in the journal Nature Communications on Wednesday, June 24, 2020.

Breast cancer is the most frequent cancer in women. The cumulated risk that a woman develops breast cancer is approximately 5% in the world, with a risk of death of 1,4%. In 2018, more than 2 million new cases were diagnosed, representing about 25% of cancer cases in the world.

Different epidemiological studies carried forth recently have improved our understanding of the factors that increase the risk of developing breast cancer. We know that less than 10% of these cases are hereditary and have a genetic origin. In most cases, the different risk factors identified are behavioural factors associated with for example poor nutrition or consumption of alcohol; hormonal factors associated with taking a contraceptive pill at a young age or for a long time or hormonal treatments taken during menopause; and finally environmental factors such as air polution or altered light/dark cycles like those encountered by nightshift workers.

It is this effect of chronic light/dark alteration on the development of breast tumors that scientists from the ONCOSTEM (U 935 Inserm/UPSaclay) and the GABI (INRAE/AgroParisTech/UPSaclay, Jouy-en-Josas) laboratories studied.

Scientists used a mouse model that spontaneously develops mammary gland tumors. The animals underwent chronic light/dark differences that experimentally reproduced a rythm of nightshift workers (an alternating day shift and night shift or jet-lag conditions). The scientists then oberved that the circadian disruption[1] had a significant impact on the development of mammary gland tumors. This disruption of the circadian rythm increased the dissemination of cancer cells and the formation of metastases in these animal models.

This study also reveals that chronic disruptions in the circadian rythm makes the immune system more permissive to the dissemination of cancer cells by modifying the tumor's micro-environment. Thus, an increase in the Cxcl5 chemokine in the tumors leads to an increased infiltration of myeloid CXCR2 + cells that favor an immunosuppressing environment. These negative effects may be corrected using a CXCR2/CXCL5 pathway inhibitor, therefore limiting the effects of circadian stress on tumor progression.

These experimental results confirm epidemiological studies showing that premenopaused women exposed through their work to disruption of light/dark cycles over long periods of time are particularly exposed to more agressive breast cancers.

These studies were financed in part by the following associations and fondations: Vaincre le Cancer, ICIG (Institut de Cancérologie et d’Immunogénétique), Fondation de l'Avenir, GEFLUC-IdF Les Entreprises contre le cancer. 

 

[1]The circadian ryhtm is defined by an alternation of a waking period, which one is awake and sleep, which lasts approximately 24 hours.

See also

Bibliography

Eva Hadadi, William Taylor, Xiaomei Li, Yetki Aslan, Marthe Villote, Julie Rivière, Gaelle Duvallet, Charlotte Auriau, Sandrine Dulong, Isabelle Raymond Letron, Sylvain Provot, Annelise Bennaceur-Griscelliand Hervé Acloque : Chronic circadian disruption modulates breast cancer stemness and immune microenvironment to drive metastasis in mice, Nature Communication 11, 3193 (2020) . DOI : 10.1038/s41467-020-16890-6