
266. immunology of the cancer cell: tumour-specific antigens
after a broad historical survey of immunological
studies of cancer, a review is given
of the evidence showing that antigens present in
normal cells are missing from the
malignant cells that arise from the same tissue.
this evidence is considered in con-
junction with the deletion hypothesis of carcinogenesis,
and the author emphasizes,
that in his view, the key event in carcinogenesis
is enzymatic deletion.  antigenic
gain and intensification in the course of spontaneous,
chemical, and viral carcino-
genesis is reviewed, together with experiments
demonstrating the existence of
tumour-specific antigens.  the question is then
posed: if tumours have specific anti-
gens, why is evidence for their rejection so scanty?
the occasional spontaneous re-
gression points to host resistance but its rarity
suggests that tolerance generally
develops.  consideration is given to the
application of immunological methods to
therapy and although current achievement
in this field is limited, new immunological
stratagems might yet transform the picture.
finally a plea is made for the integra-
tion of the disciplines of immunology and
cellular differentiation.  the prospect is
raised that through a synthetic and holistic
approach we might discover the suscepti-
bility of the cancer cell to re-differentiation
and re-recognition.
