HGNC Approved Gene Symbol: CYP4B1
Cytogenetic location: 1p33 Genomic coordinates (GRCh38): 1:46,799,046-46,819,413 (from NCBI)
Nhamburo et al. (1989) identified a new P450 expressed in human lung. They isolated a cDNA coding for it from a lambda gt11 library constructed from human lung mRNA using a probe to rat P450IVA1. P450IVB1 mRNA was undetectable in livers from 14 persons including those from which the lungs were derived.
Thum and Borlak (2000) investigated the gene expression of major human cytochrome P450 genes in various regions of explanted hearts from 6 patients with dilated cardiomyopathy and 1 with transposition of the arterial trunk and 2 samples of normal heart. mRNA for cytochrome 4B1 was predominantly expressed in the right ventricle. A strong correlation between tissue-specific gene expression and enzyme activity was found. Thum and Borlak (2000) concluded that their findings showed that expression of genes for cytochrome P450 monooxgenases and verapamil metabolism are found predominantly in the right side of the heart, and suggested that this observation may explain the lack of efficacy of certain cardioselective drugs.
Imaoka et al. (2000) developed a microassay for CYP4B1 mRNA by performing RT-PCR. Using this method, they assayed CYP4B1 mRNA levels in transurethral resection samples from the bladders of patients with bladder tumors and compared the levels with those from nonbladder tumor patients and from nontumor sections from the patients with bladder tumors. The bladder tumor patients had a significantly high expression of CYP4B1 in both tumor and normal tissue from their bladder than the nonbladder tumor patients.
By study of rodent/human somatic cell hybrids, Nhamburo et al. (1989) assigned the CYP4B1 gene to 1p34-p12.
Imaoka, S., Yoneda, Y., Sugimoto, T., Hiroi, T., Yamamoto, K., Nakatani, T., Funae, Y. CYP4B1 is a possible risk factor for bladder cancer in humans. Biochem. Biophys. Res. Commun. 277: 776-780, 2000. [PubMed: 11062028] [Full Text: https://doi.org/10.1006/bbrc.2000.3740]
Nhamburo, P. T., Gonzalez, F. J., McBride, O. W., Gelboin, H. V., Kimura, S. Identification of a new P450 expressed in human lung: complete cDNA sequence, cDNA-directed expression, and chromosome mapping. Biochemistry 28: 8060-8066, 1989. [PubMed: 2574990] [Full Text: https://doi.org/10.1021/bi00446a014]
Thum, T., Borlak, J. Gene expression in distinct regions of the heart. Lancet 355: 979-983, 2000. [PubMed: 10768437] [Full Text: https://doi.org/10.1016/S0140-6736(00)99016-0]