[Cloning and sequence analysis of human embryonic nasopharyngeal epithelial CYP2E1 cDNA].
OBJECTIVE
To investigate the role of CYP2E1 gene in chemical carcinogen-induced nasopharyngeal carcinogenesis and to provide new evidence about etiology and pathogenesis of nasopharyngeal carcinoma.


METHODS
RT-PCR was used to clone the CYP2E1 gene in human embryonic nasopharyngeal epithelial (HENE) cell, the transformed nasopharyngeal epithelial cell line (7,429), and the nasopharyngeal carcinoma cell line (HNE1). The cloned segments were inserted into pGEM-T Easy vector to sequence by DNA recombination technique.


RESULTS
In comparison with HENE-2E1 cDNA, there were two point mutations at positions 846 (A to T) and 901 (A to G) in 7,429-2E1 cDNA as well as only one point mutation at position 901 (A to G) in HNE1-2E1 cDNA. In comparison with human (adult, ethanol-inducible) liver CYP2E1 gene (GenBank NO. J02843), HENE-2E1 cDNA had one point mutation at position 901 (G to A). All these point mutations didn't affect the amino acid sequence. But no base change was found in HNE1-2E1 cDNA.


CONCLUSIONS
There are a few of base substitutions among HENE-2E1 cDNA, 7,429-2E1 cDNA, and HNE1 cDNA sequences. All these point mutations are synonymous mutation. The study reconfirms that the human CYP2E1 gene is relatively well conserved.
Hou
De-fu
DF
Cancer Research Institute, Xiangya School of Medicine, Central South University, Changsha 410078, China.
He
Zhi-min
ZM
Yang
Fang
F
D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D019392:Cytochrome P-450 CYP2E1 / Q000096:biosynthesis* / Q000235:genetics; D018076:DNA, Complementary; D004622:Embryo, Mammalian; D006801:Humans; D008969:Molecular Sequence Data; D009303:Nasopharyngeal Neoplasms / Q000235:genetics / Q000473:pathology*; D009305:Nasopharynx / Q000166:cytology / Q000473:pathology*; D017354:Point Mutation; D017422:Sequence Analysis, DNA; D014407:Tumor Cells, Cultured
D018076:DNA, Complementary; D019392:Cytochrome P-450 CYP2E1