Evening star., 1951-04-16
Laboratory Troins Virus
To Attack Cancer Cells
Accidental Discovery Leeds
To Research Development
By Thomas R. Henry

NAuScS, u1OSt minute pdT C1ClES Oh gl40
far too small to be seen with any optical
microscope. are being trained as pre-
datory animals to attack cancer cells
and leave normal body cells unharmed.
Progress in this remarkable new ap-
proach to the cancer problem is des-
cribed in report Just issued by the
American Cancer Society.
Some time ago it was found acci-
dentally that if the virus responsible
for nervous system disease known as
Russian influenza were inoculated in
mice with cancer 1t would attack the
cancer cells selectively and greatly slow
down their growth. Later, however, it
would infect and kill the normal tissues
Of the mice.
In experiments conducted at the Me-
mortal Cancer Center in New York
under a society grant. however. it has
been found that If this virus Is grown
in test tube entirely on cancer tissue
few elements are produced which
are especially destructive to, maligant
growths while they have little effect
on normal cells. Some particles fail
to be trained, however, and remain to
infect and kill the mouse long after the
cancer has been destroyed.
Mice Increasing In Weight.
To date, six different viruses have
been trained to seek out and destroy
cancer cells. according to the report. BY
training from a single individual type
two kinds of virus particles have been
developed, one with the power to at
tack only normal cells and the other only
virus cells. A major problem now is
to separate them. It is possible that this
may be done by killing the virus which
acts against normal cells, at the same
time leaving unharmed the cancer at
tacking variety. A second means has
been developed. it now appears, by
which the virus which kills normal
tissue of mice can be removed from the
mixture. This discovery has led to the
ability to kill one form of cancer in
fowls with a virus normally fatal to
the bird which has been made innocuous
by this means.
In other experiments mould has been
found which forms, under certain con-
ditions, a substance very toxic to the
cells of animal cancer. 1t still, however,
is quite injurious to the normal tissue OF
the host and cures have been rare.
A new race of giant mice has just
been reported to the American Genetic
Association here.
In three months these mice reach q
weight as much as three times that
of normal mice of the same variety.
according to the report in the journal
of Heredity by Ann M. ingalls, and her
associates of the Jackson Memorial
Laboratory of Bar Harbor, Me.
The new type appeared suddenly as
a mutation among stock mice kept for
experimental work. 1t undoubtedly Is
a hereditary change Of the type known
as recesSive, the same as that responsible
for the bleeding disease of European
royal families.
Six Different Viruses Used.
At birth the giant mice are Of the
same shape and general appearance as
ordinary mice. This continues until
they are three or four weeks old. at
which time they seem to have slightly
shorter bodies and are rather square.
From that time on they increase In
weight rapidly so that at about. three
months they weigh twice as mitch as
their litter mates, who are at about
the end of their growth period. The
giants, however, continue to grow.
They apparently have about the same
life span as other mice. None have
died up to II months Of age, fairly
normal life span.
The giants themselves are sterile.
They reappear however, among the off,
spring of apparently normal litter mates
who carry, and are likely to carry for
many generations, the hereditary fac
tor responsible for the excessive fat-
ness. Eventually. 1t is to be expected,
the fat race will disappear.
Other factors for obesity have been
known among mice, usually linked with
other hereditary factors. but IN no
other case has there been anything as
pronounced as this
The fatness may be considered, 1t Is
pointed out, as form of hereditary
disease which in nature would be
great handicap to the animals.