CELLULAR ADAPTATION AS A RESPONSE 117In view of the many different cellular and tissue biological processes that
make up the long, complicated carcinogenic process, it seems highly prob
able that physiological-adaptive and confrontational-adversarial compo
nents are both present at different times and to different degrees. It appears
attractive to me to consider the early and intermediate steps in the carcino
genic process as mainly physiological-adaptive, while the stages of frank
malignancy with progression as showing more confrontational-adversarial
properties.
The very early initial interactions of mutagenic chemical carcinogens,
radiations, and viruses with DNA would obviously prejudice most of us to
consider the adversarial “abnormal” view as the appropriate one. Yet, I
cannot overemphasize the unusually common nature of the earliest altered
rare cells that appear during carcinogenesis, their unusually bland nature,
and their spontaneous differentiation to normal-appearing adult liver. In
my opinion, there is virtually no evidence to support the view that the rare
altered cells appearing after initiation are in any way “abnormal” in their
behavior. The finding of structural alterations in some genes after initiation
does not prove by any stretch of the imagination that they are playing any
role as determinants and that the new rare cell is biologically a mutant.
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