The occurrence of
lung cancer is associated with smoking, which exposes smokers to a series of carcinogenic chemicals. CYP (
cytochrome P450) usually metabolizes
carcinogens to their inactive derivatives, but occasionally convert the chemicals to more potent
carcinogens. In addition to the metabolism of carcinogenic compounds, CYP also participates in the activation and/or inactivation of
anti-carcinogenic agents, suggesting that the local CYP expression in
lung cancer and surrounding tissues could be an important determinant of efficacy of anticancer drugs. Furthermore,
CYP19 (
aromatase),
estrogen synthase P450, expressed in more than 80 percent of non-small cell
lung cancers. It suggests an association between
estrogens and
cancer development, which makes
aromatase an attractive therapeutic target for the treatment of
lung cancer. 1alpha,25-Dihydroxyvitamin D3 has an inhibitory effect on the proliferation of
cancer tissues, and is converted to its inactive 24-hydroxylated derivatives by CYP24, which is frequently expressed in
lung cancer tissues. Therefore, understanding the CYP expression in
tumor tissues is important in developing better
therapies for
lung cancer, and may lead us to standardized, tailor-made
therapies for individuals.