Detoxification represents the second phase of carcinogen metabolism in human body, followed by bioactivation of procarcinogens
A focus on CYPs, in particular on CYP1s, arises from the role they play in the activation of procarcinogens
. CYPs involved in the initiation of carcinogenesis have become the targets for anticancer strategy [18,19].
CYP2E1 can also activate toxic compounds and procarcinogens
found in tobacco smoke and nitrosamine compounds [26-33].
Yamazaki et al., "Activation of chemically diverse procarcinogens
by human cytochrome P450 1B1," Cancer Research, vol.
Phytochemicals, particularly the thiol class such as sulforaphane, have also been shown to inhibit the conversion of procarcinogens
to their electrophilic, DNA damaging, chemicals (32,33).
Bioflavonoids and environmental procarcinogens
have similar molecular structures and can often act as ligands for the same aryl hydrocarbon receptor (AHR).
CYP1A2 plays an important role in the metabolism of several clinically used drugs, including theophylline, clozapine and tacrine, and foodborne procarcinogens
such as polycyclic aromatic hydrocarbons or imidazoquinoline derivatives (Faber et al.
Reduce the carcinogenic effect of aflatoxin through use of chemopreventive agents such as Oltipraz, green tea polyphenols, and Sulforaphane, which trigger detoxifying enzymes or inhibit enzymes required for the activation of procarcinogens
Inhibition by green tea catechins of metabolic activation of procarcinogens
by human cytochrome P450.
These reactions are important for the bioactivation of exocyclic amine containing procarcinogens
and for the metabolism of some pharmaceutical drugs .
Pomegranate compounds suppress enzymes in the intestine and liver that convert certain molecules (procarcinogens
) into cancer-causing agents.
(55) COX2 activates procarcinogens
, promotes angiogenesis, and indirectly increases free radical production.