Expression analysis of CYP27B1 in tumor biopsies and cell cultures.

There is evidence for alternative splicing as a prevalent mechanism both in normal human cells and cancer cells. Alternative splice variants of the gene encoding the human 25-hydroxyvitamin-D3-1alpha-hydroxylase (CYP27B1) in human glioblastoma were recently reported. Using combined nested and touchdown PCR, full length CYP27B1 as well as several splice variants were cloned. Here, this approach was used to analyze the expression of CYP27B1 and its splice variants in normal tissues, tumor tissues and cell cultures. Expression of CYP27B1 was found in all tumor tissues. The expression of CYP27B1 was also found in several normal tissues including lung, kidney, placenta, thymus and stomach and in derived cell cultures. The expression of splice variants of CYP27B1 were detected in 1 out of 3 tested brain samples, with no evidence for the expression of normal CYP27B1.