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Scientists Report Experimental Therapy Eliminates Cancer Cell Growth
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http://enews.voanews.com/t?ctl=15F1A55:A6F02AD83191E1604A04F8D30CF7CABF9574F7DCC14957C0 Researchers say
so-called jump-starting of gene implicated in development of cancer
may lead to cure for cancer in humans Scientists report they have
manipulated a gene implicated in the development of cancer so it stops
the growth of cancer cells in mice.  VOA's Jessica Berman reports the
researchers say the so-called jump-starting of the gene may lead to a
cure for cancer in humans.

P53 is one of the most important genes in the development of cancer. 
When it is functioning properly, it keeps other cellular mutations
that could lead to cancer in check.  When damaged, P53 no longer stops
other genetic abnormalities, facilitating the growth of malignant
cells.

The powerful effect of P53 was written up in two studies published in
the journal Nature.

When a team of researchers at Cold Spring Harbor Laboratory in New
York introduced and genetically jump-started P53 in a cancerous mouse,
the gene put a liver tumor into an inert state known as senescence and
the tumor gradually disappeared. 

A separate group of cancer investigators at the Massachusetts
Institute of Technology discovered something similar with the
reactivation of P53 in sarcoma, a connective tissue cancer, and
lymphoma, a cancer of the lymph glands.

The sarcoma became senescent and the cancerous lymphoma cells, just
like healthy cells, began to kill themselves in a programmed fashion,
a process known as apoptosis.

Andrea Ventura is lead author of the MIT study.  Ventura says the
research proves the concept that jump-starting gene P53 appears to
reverse cancer, but he says people should not get too excited just
yet.

"What we see in mice not always happens in humans, but we think it is
a very strong indication that similar approaches might work for human
patients as well," she noted.

Ronald DePinhol is head of the center for applied cancer research at
Dana-Farber Cancer Institute in Boston.  He says P53 is the most
important of tumor suppressors in human cancer.

"It is inactivated as a virtual rite of passage for cancer cells to
become malignant. And finding ways to commandeer or reactivate the
pathway therapeutically would be of enormous value for cancer
therapy."

But DePinhol says P53 is but one of many regulators involved in the
development of cancer, and that 90 percent of cancer therapies
eventually fail.

"Cancer is the culmination of many genetic aberrations that
essentially endow would-be cancer cells with an array of biological
capabilities," he added.

In a commentary he wrote for Nature, DePinhol says he hopes the work
with gene P53 will lead researchers to find more defective tumor
suppressors that cause cancers to thrive, so new drugs can be
developed to reactivate the cancer preventing genes.


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