Scientists Identify Genes Capable of Regulating Stem Cell Function
News Sep 22, 2008
Scientists from The Forsyth Institute, Boston, MA, and the Howard Hughes Medical Institute at the University of Utah School of Medicine have developed a new system in which to study known mammalian adult stem cell disorders.
This research, conducted with the flatworm planaria, highlights the genetic similarity between these invertebrates and mammals in the mechanisms by which stem cell regulatory pathways are used during adult tissue maintenance and regeneration. It is expected that this work may help scientists pursue pharmacological, genetic, and physiological approaches to develop potential therapeutic targets that could repair or prevent abnormal stem cell growth which can lead to cancer.
In recent years, planarians have been recognized as a powerful model system in which to molecularly dissect conserved stem cell regulatory mechanisms in vivo. This research reveals that planaria are also a great model in which to study the molecular relationship between stem cells and cancer.
The gene characterized in this study (PTEN) is one of the most commonly mutated genes in human cancers. As in human beings, genetic disturbance of the gene in planarians led to mis-regulation of cell proliferation resulting in cancer-like characteristics. These results indicate that some of the pattern control mechanisms that enable regeneration of complex structures may go awry in cancer.
Abnormal stem cell proliferation in planarians is induced by genetic manipulation of conserved cellular signaling pathways. These abnormal cells can be specifically targeted without disturbing normal stem cell functions that support adult tissue homeostasis and regeneration.
Importantly, this type of analysis could not be achieved in more traditional adult invertebrate model systems such as the fruit fly Drosophila and the nematode C. elegans. This research will be published in the journal Disease Models & Mechanisms available online on August 30.
According to the paper’s lead author, Dr. Nestor J. Oviedo, an Assistant Research Investigator in the Forsyth Center for Regenerative and Developmental Biology, this work provides new opportunities to expand knowledge of this regulatory molecule and the role it plays in cancer and tissue regeneration.
“Our findings demonstrate that important signaling pathways regulating adult stem cell proliferation, migration and differentiation are evolutionarily and functionally conserved between planarians and mammals. Planarians are poised to not only advance the understanding of how diverse adult tissues are functionally maintained in vivo, but also will enhance our capabilities to identify, prevent, and remediate abnormal stem cell proliferation.”
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