Phlogiston theory was a conceptual breakthrough that helped chemists conduct experiments and share ideas. Only when it came to pinning down the distinctive physical properties of phlogiston did it become clear that no such thing exists. Now an opinion piece by Arthur Lander, published in BioMed Central's open access Journal of Biology, argues that the idea of stem cells—a major conceptual breakthrough in biology—is running into similar troubles as investigators try to pin it down to a set of distinctive molecular characteristics.
Professor Lander, Director of the Center for Complex Biological Systems at the University of California, Irvine, USA, argues that neither of the two properties that define 'stem cells' as they are popularly discussed, potency and self-renewal, can be ascribed an exclusive molecular basis, and that both are seen in cell types not usually described as stem cells. He said, "It is curious that, after 45 years, we are unable to place the notion of 'stemness' on a purely molecular footing. Of course, the fact that a goal has not been achieved after a long time does not mean that the answer is not around the corner. But it does give one cause to wonder whether something we are doing needs to change, either in the question we are asking or the way we are approaching it".
Lander writes that 'stemness' should be considered a property of systems, rather than individual cells, describing how a system with stemness is one that can achieve a controlled size, maintain itself homeostatically, and regenerate when necessary. He argues that such behaviors naturally emerge as a consequence of basic engineering principles of feedback control. This is more than a minor semantic quibble - just one practical consequence of an inaccurate understanding of the precise nature of stem cells may be the assumption that specific chemotherapeutic targeting of 'cancer stem cells' will necessarily stop tumors in their tracks. As Lander writes, "If feedback and lineage progression continue to take place in cancerous tissues, we might observe that under different conditions - different stages of tumorigensis, different parts of a tumor, different amounts of tumor cells - that different cell types will assume the role of cancer stem cell".
He concludes, "Like phlogiston, the term 'stem cell' is a scientific concept. Just as investigating the concept of phlogiston allowed the discovery of oxygen and the process of oxidation, it may be that by refashioning our thinking about stem cells – with systems relationships and dynamics taking the place of molecular signatures and simple gene regulatory circuits - the concept of stemness will continue to light the path toward understanding".
Notes to Editors1. The 'stem cell' concept: is it holding us back?
3. BioMed Central (http://www.biomedcentral.com/) is an STM (Science, Technology and Medicine) publisher which has pioneered the open access publishing model. All peer-reviewed research articles published by BioMed Central are made immediately and freely accessible online, and are licensed to allow redistribution and reuse. BioMed Central is part of Springer Science+Business Media, a leading global publisher in the STM sector.
Modern genetic sequencing tools give clearer picture of how corals are related
17.08.2017 | University of Washington
The irresistible fragrance of dying vinegar flies
16.08.2017 | Max-Planck-Institut für chemische Ökologie
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
17.08.2017 | Physics and Astronomy
17.08.2017 | Earth Sciences
17.08.2017 | Physics and Astronomy