An international team of scientists has announced a new
advance in the ability to target and destroy certain cancer cells.
A group led by the University
of Leicester has shown
that particular cancer cells are especially sensitive to a
protein called p21. This protein usually forces normal and cancer cells to stop
dividing, but it was recently shown that in some cases it can also kill cancer cells.
However, scientists
have been unclear about how this happens.
Researcher Salvador Macip, from the University of Leicester Department of
Biochemistry, said: “If we could harness this ‘killing power’ that p21 has, we
could think of designing new therapies aimed at increasing its levels in tumors.
This is what motivated us to look into it.”
Now the team from the universities of Leicester and Cardiff
in the U.K., University of South Carolina,
and Karolinska Institutet, Sweden, has discovered that cells
from sarcomas tend to die in response to p21
and that this is determined by the sensitivity of their mitochondria
to
oxidants.
They have published their findings in The Journal
of Biological Chemistry. The research was funded by the MRC, the NIH,
CONACYT, and the Swedish Cancer Society.
Macip added: “Our research also showed that p21 can kill cells
even in the absence of p53, a protein that is in the main responsible for cell death
but is inactivated in most cancers.
“This shows that certain types of cancer, sarcomas for instance, but
maybe also others, should respond well to drugs that increase the levels of
p21, even if they don’t have an active p53. The side effects of these therapies
should be minimal, since our experiments show that normal cells
would arrest but not die in response to p21.
“There are already drugs available that selectively increase p21. Our results
provide a rationale for testing them in certain types of cancers,
which could be identified using the experiments we describe.”
