Greek scientists find way to weaken cancer cells





Posted: March 01, 2004


ATHENS (Reuters) - Greek scientists said they have found a way to
lower cancer cell resistance to medical treatment in what could be a
major step in treating a disease that kills more than six million
people every year.


The procedure, which only recently started testing on animals, could
make chemotherapy more effective at significantly reduced dosages and
eliminate many of its side effects.

The key lies in "switching off" apolipoprotein J, also known as
clusterin or Apo J for short, a protein used by healthy and diseased
cells alike as a shield against attacks, Stathis Gonos, leader of the
research team, told Reuters on Monday.

"Our research was looking at genetic and environmental factors
related to aging, and that is how we found the function of Apo J in
healthy cells is to act as a shield, or 'survival factor,' against
toxic factors in the environment," Gonos said.

"Our next step was to investigate whether Apo J has a similar
function in cancer cells, and indeed (we) saw that it retains the
same function of defending cells, shielding them from e.g.
chemotherapy prescribed by a doctor to treat cancer," he added.

Cells react to what they perceive as an assault with all the weapons
they have, producing vast quantities of Apo J as a shield against the
attack, be that an infection or an anti-cancer drug.

"We used a new technology called RNA interference to silence the
expression of Apo J and saw that in the case of cancer cells they
became a lot more fragile and this made it a lot easier to kill them
with normal chemo," Gonos said.

"We had spectacular results even when using a tenth of the usual
dosage," he added, "and this means that many of the side effects of
chemotherapy will likely disappear as we are able to reduce dosages."

Many patients undergoing chemotherapy experience anemia, nausea, hair
loss or infection due to low blood cell counts.

The Greek team, which is financed by the European Union, has
submitted a global patent application in partnership with Canadian
biotech firm OncoGeneX and scientists from the University of British
Columbia.

The researchers have recently started animal trials at Vancouver
General Hospital, and Gonos forecasts human trials will start in
between three and five years.

According to data from the World Health Organization's World Cancer
Report, in the year 2000 alone around ten million people worldwide
developed a malignant tumor and more than six million died of the
disease.