IndexA standard chronotherapy todayThe mononuclear cell modelTimeTime medicine has (finally) the wind in its sails. Driven by the recognition of the 2017 Nobel Prize (for the discovery of the biological mechanisms of the circadian clock), tools are being developed at a rapid pace to move towards personalized chronomedicine. A Chicago team from Northwestern University proposes in "PNAS" a simple test called "TimeSignature" to determine the biological clock of each individual. This innovative approach is based on a powerful algorithm that allows you to request only two blood samples. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essayA standard chronotherapy todayFor Prof. Francis Lévi, pioneer in cancer timing, now coordinator of the associated European laboratory Inserm/Warwick on the personalization of chronotherapy: «Today we know how to do group chronotherapy, we know for example that it is better to give glucocorticoids in the morning, NSAIDs in the afternoon or evening, fluorouracil in the first night, oxaliplatin in the early afternoon or irinotecan in the afternoon. very early in the morning. But what about subjects with altered, decoupled, out of sync or even non-existent rhythms? This is the question that tests of this type must answer. There are already many indicators of the human biological clock, such as melatonin at night or peak cortisol in the morning. But as Étienne Challet, head of the "Circadian clocks and metabolism" team at the Institute of Cellular and Integrative Neurosciences (CNRS/University of Strasbourg), explains: to have the phase of an individual, the methods are cumbersome, with repeated samples. The mononuclear cell model The biological clock is a multi-oscillating system, with a central clock orchestrating the timing of peripheral clocks. The Chicago researchers used mononuclear cells called PBMCs (peripheral blood mononuclear cells). “These cells have the characteristic of having a peripheral clock in phase with the main clock,” explains Étienne Challet. Rosemary Braun's team has successfully developed an algorithm to determine an individual's internal time from the level of messenger RNA expression in these cells. »An interesting test but to be validated.Remember: this is just an example.Receive a personalized paper from our expert writers now.Receive a personalized essayThe TimeSignature tool has not yet been tested, says Francis Lévi. “The test was developed on healthy subjects,” he explains. Interpatient variability is not necessary, especially in sick subjects. No model does not take into account individuals who have profound disruption of the circadian rhythm. It is not known how tests of this type behave in sick people. »For this pioneer who has been working on the topic for more than 30 years, the problem is one of concepts. “These molecular biology papers assume that the clock works equally for everyone,” he continues. However, this is not true. This new data must converge with medical expertise and these tests must be tested prospectively in protocols. "A European project coordinated by Prof. Levi is currently testing the combination with biomarkers such as wakefulness/activity rhythm, temperature, sleep, continuously measured via sensors.