phytohaemagglutinin reduces fatty tumours

Doug Skrecky (oberon@vcn.bc.ca)
Mon, 1 Jun 1998 08:28:37 -0700 (PDT)


Authors
Pryme IF. Pusztai AJ. Grant G. Bardocz S.
Institution
Department of Biochemistry and Molecular Biology, University of Bergen,
Norway.
Title
The effect of switching between a phytohemagglutinin-containing and a control
diet on the growth and lipid content of a Krebs II lymphosarcoma tumor.
Source
J Exp Ther Oncol. 1(5):273-7, 1996 Sep.
Abstract
The present study concerns the importance of the timing of feeding mice a
PHA-containing diet (7 mg g-1 diet) on tumor formation. The major decrease in
tumor weight occurred in mice fed on the PHA diet for 11 days. A marked
reduction was also observed in animals pre-fed for 3 days with PHA before
tumor cells were injected and the diet then changed to lactalbumin, La. A
large decrease in tumor weight was also evident when a change of diet from La
to PHA was made on the day of tumor cell inoculation. Despite the presence of
the developing tumor PHA was able to induce hyperplasia of the small
intestine in all groups of animals fed PHA during a part or the whole of the
experiment. The dry weights of tumors attained in each of the experimental
groups plotted as a function of duration of PHA feeding, and the percentage
lipid content of the tumors, mirrored almost exactly one another, suggesting
that the availability of essential lipid material is severely reduced by the
lectin. This would appear to have a major effect on the observed reduction in
tumor growth.

Authors
Pryme IF. Pusztai AJ. Grant G. Bardocz S.
Institution
Department of Biochemistry and Molecular Biology, University of Bergen,
Norway.
Title
Phytohemagglutinin-induced gut hyperplasia and the growth of a mouse
lymphosarcoma tumor.
Source
J Exp Ther Oncol. 1(3):171-6, 1996 May.
Abstract
NMRI mice injected subcutaneously with Krebs II lymphosarcoma cells and fed
on a diet containing the kidney bean lectin phytohemagglutinin (PHA) within
the range 0.45-7.0 mg/g diet, developed tumors during a 10 day period which
on average were only 35% of the dry weight of tumors in lactalbumin (La) fed
mice (control). The reduction in growth occurred in a dose-dependent manner
in the range 0.45-3.5 mg/g diet. The degree of hyperplasia of the small
intestine in response to feeding the PHA diets was higher in non-injected
compared to injected mice. A lipolytic effect of PHA was observed above 1.75
mg/g diet in control mice and the highest concentration had a major effect on
body weight. Since the index of hyperplasia at the lowest PHA concentration
tested did not correlate with the reduction in tumor size, it is suggested
that other factors in addition to the initial lectin-induced gut hyperplasia
are involved in slowing down the progression of tumor growth.