Biomedical Engineering Reference
In-Depth Information
This demonstration of plasticity suggests the possibility that a cancer cell can
assume and discard stem cell-like characteristics, and that the products of
normal cells in the environment may contribute to this process (Weinberg
2007; Mani et al. 2008).
Thus the model of cancer progression through accumulated genetic
mutations and a process involving selection of the fittest cells that can spread
and metastasize may be modified to create a new model, in which phenotypic
plasticity enables reversible alterations in the expression of genes critical for
invasion and metastasis.
These recent discoveries have tremendous implications for our understanding
of the process of malignant transformation and for our approach to devising
mechanism-based treatments for cancer. Cancer cells with stem cell-like qualities
(which include a relative resistance to chemotherapy and radiation therapy) must
be targeted in our development of new anti-cancer therapies.
The model of cancer stem cells outlined above is recent and undoubtedly will
undergo modification as further knowledge accumulates. There are fundamental
differences between cells that produce normal tissues and cancer cells with stem
cell-like qualities, which need to be better understood. And it remains to be
determined whether the latter are derived from the cells that produce normal
tissues. This topic brings together outstanding international experts explaining
our current understanding of basic principles of cancer stem cells. This topic
provides timely, cutting-edge information about cancer stem cells from the
perspectives of both the basic and clinical sciences and will help researchers
move with greater speed towards designing more effective treatments for cancer.
Urgency derives from the human cost of cancer. Since cancer will occur in
over 40%of Americans and the death rate from cancer is over 500,000 per year,
cancer stem cells are a subject worthy of intensive research by basic,
translational, and clinical investigators whose goal is to improve these statistics.
And so scientists continue to revisit the conceptofstemcells,nowwithnuances
that include plasticity and more clearly defined interactions between the cell and its
environment, but with many open questions demanding further exploration.
We dance round in a ring and suppose,
But the Secret sits in the middle and knows.
Robert Frost, The Secret Sits
Houston, USA
John Mendelsohn
