Evening star., 1936-10-27
STARS, MEN AND ATOMS
Notebook of Science Progress in Field,
Laboratory and Study.
TUnA<c urNpv
BY THOMAS r. HENRY.

Powerful inhibiting effects of lysine,
one Of the amino acids, on both normal
and malignant growths have been Demon
strated in experiments by Public Health
Service pharmacologists at the National
Institute Of Health here-thus opening
. new approach to study Of the mech
anism. and possibly the treatment, Of
cancer.
Lysine, . nitrogen-containing acid, Is
contained In many proteins which form
an essential part Of the diet, Is ex-
tracted in the process Of digestion and
enters into the chemical structure of
most cells In the animal body. Nearly
20 years ago 1t was demonstrated that
the rate Of growth Of young mice on =
diet from which lysine containing foods
had been removed was greatly retarded,
or even stopped altogether. The con-
clusion was reached that one OF the chief
functions Of this amino acid was that of
. growth promotion agent. A cell de-
prived Of 1t could not give rise to new
cell.
At the time these experiments were
announced very little was known about
the role played by other agents, especially
some OF the vitamins, in promoting
growth, and the diets used probably were
deficient in these substances as well as
IN lysine. To clear up this doubt the
Public Health Service pharmacologists,
DR.. Carl Voegtlin and Dr. j. w. Thomp.
son, experimented with lysine deficiency
on the growth curves Of young rats which
otherwise were given . standard diet
known to be adequate for normal growth.
The results OF the earlier investigators
were entirely confirmed. Growth was
slowed down enormously, 90 that 1t was
almost at Q xtandstill. The rats were
allowed TO eat ~ much as they wanted,
70 there could be no question OF their
failure to grow because they were not
getting enough to eat.
Now, Drs. Voegtlin and Thompson rea-
soned, II lack Of lysine will inhibit normal
growth in the young 1t also should In.
hfbit cancer growth, which presumably
depends upon the same mechanism Of
cell division, but Is anarchistic, whereas
ordinary growth II rigidly controlled.
Hence they tried the effects Of the lysine-
deficient diet on mice afliicted with .
form Of spontaneous cancer which may
be very similar to one type Of human
cancer.
The effects were the same The diet
consisted Of 80 per cent whole milk
powder, and 20 per cent ground wheat.
with minute additions Of yitamin- mate
rials and various chemical substances.
Upon this the mouse cancers grew rap
idly and soon killed the animals. Then
the milk powder was treated with q
special heating process which did not
actually destroy the lysine it contained,
but apparently made it unavailable for
physiological utilization. With the new
diet the cancers either stopped growing.
or the rate Of growth was greatly slowed
down-the. effects varying with different
animals and with different tumors on
the same animal.
The earlier experiments had showed
that while lysine was essential to growth
IN the young It apparently was not essen
tial to the maintenance Of weight and
ordinary good health after the growth
period had stopped, With these mice
about the only part Of the body which
was growing was the cancer. They no
longer needed . growth stimulus for the
rest Of the body.
8ut because Of the different rates ut
which growth was slowed down. Drs.
voegtlin and Thompson experime1ted
further by further reductions Of the little