  Cold atmospheric plasma (CAP) is a promising new agent for (selective) cancer
treatment, but the underlying cause of the anti-cancer effect of CAP is not
well understood yet. Among different theories and observations, one theory in
particular has been postulated in great detail and consists of a very complex
network of reactions that are claimed to account for the anti-cancer effect of
CAP. Here, the key concept is a reactivation of two specific apoptotic cell
signaling pathways through catalase inactivation caused by CAP. Thus, it is
postulated that the anti-cancer effect of CAP is due to its ability to
inactivate catalase, either directly or indirectly. A theoretical investigation
of the proposed theory, especially the role of catalase inactivation, can
contribute to the understanding of the underlying cause of the anti-cancer
effect of CAP. In the present study, we develop a mathematical model to analyze
the proposed catalase-dependent anti-cancer effect of CAP. Our results show
that a catalase-dependent reactivation of the two apoptotic pathways of
interest is unlikely to contribute to the observed anti-cancer effect of CAP.
Thus, we believe that other theories of the underlying cause should be
considered and evaluated to gain knowledge about the principles of CAP-induced
cancer cell death.
