The production of 27HC in lung cancer cells was not be determined in this study, however, there is accumulating evidence that CYP27A1 mRNA expression correlates with its protein expression and enzymatic activity, and also that CYP27A1 expression correlates with the levels of its product 27HC in various types of cells and also in vivo (41–43). The gene discussed is CYP27A1; the disease is lung carcinoma.