Differential expression of a cDNA clone in human liver versus hepatic cancer--highly homologous to aryl-dialkyl-phosphatase.
We applied the technique of mRNA differential display to normal liver tissue and hepatoma cell line Hep3B. One of the isolated cDNA clones was expressed in human normal liver tissue but not in the human hepatocarcinoma cell line. Northern Blot analysis confirmed that high level of mRNA was expressed in human normal liver tissue but the level was decreased in non-cancerous liver tissue from hepatoma patients. Low level or no expression was observed in human hepatoma tissue. One of these transcripts was about 1.8 kb in length. Southern Blot analysis showed that it was a single copy gene. We obtained a full length cDNA clone of 2,395 bp by screening human liver 5'-stretch plus cDNA library. Nucleotide sequence indicated that this clone was highly homologous to aryl-dialkyl-phosphatase and possessed two polymorphic sites. Aryl-dialkyl-phosphatase which has a prominent role in the metabolism of several toxic, synthetic compounds, may be potentially related to human hepatocarcinoma susceptibility. The biological significance of its differential expression in normal versus malignant tissue is discussed.
Wang
K K
KK
National Laboratory for Oncogenes and Related Genes, Shanghai Cancer Institute.
Wan
D F
DF
Qiu
X K
XK
Lu
P X
PX
Gu
J R
JR
D000595:Amino Acid Sequence; D043303:Aryldialkylphosphatase; D001483:Base Sequence; D006528:Carcinoma, Hepatocellular / Q000737:chemistry*; D003001:Cloning, Molecular / Q000379:methods; D018076:DNA, Complementary / Q000235:genetics; D004950:Esterases / Q000235:genetics*; D018628:Gene Dosage; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology; D005796:Genes; D006801:Humans; D008099:Liver / Q000737:chemistry*; D008113:Liver Neoplasms / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000032:analysis*; D012334:RNA, Neoplasm / Q000032:analysis; D014407:Tumor Cells, Cultured
D018076:DNA, Complementary; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D004950:Esterases; D043303:Aryldialkylphosphatase