Activation of stem cells is the first step towards lung cancer

In the lungs, as in all other organs, there are tissue-specific stem cells that are involved in tissue repair after damage. A study conducted under the supervision of Professor Barry R. Stripp at Duke University Medical Center (USA) has demonstrated that with serious lung damage, stem cells become a source of new actively dividing cells.

The scientists used a chimeric animal model: ordinary mice were injected with stem cells expressing green fluorescent protein (GFP). Penetrating into the lungs, the stem cells remained dormant. Then the destruction of the lung epithelium was provoked in mice by acting with a toxic substance – naphthalene. At the same time, the "green" stem cells began to actively divide, forming a new epithelium. Considering that with frequent cell division, the probability of secondary mutations of its genome increases, which lead to cancer degeneration, it can be assumed that the constant activation of stem cells in chronic lung diseases and exposure to cigarette smoke toxins is the main cause of cancer development.

The authors suggest that understanding the mechanism of the described process will give the key to the development of pharmacological activation of lung repair, understanding the mechanism of cancer development and methods of its prevention.

In the drawings:
On the left – the normal respiratory tract of a chimeric mouse. Stem cells expressing green protein are distributed evenly, on a par with ordinary cells.
On the right – the same airways after chemical exposure. Most of the normal lung epithelial cells have died, and activated green stem cells form "patches" of new dividing cells.

Portal "Eternal youth" http://vechnayamolodost.ru according to Physorg: Activated stem cells in damaged lungs could be first step towards cancer28.05.2009