RESUMO
The cDNA clones, which were highly expressed in liver tissues of hepatocellular carcinoma (HCC) patients, were identified using dot hybridization and reconfirmed by Northern blot analysis. One of the clones, ninjurin (nerve injury induced protein), showed a much higher expression level in the liver tissue of HCC patients than in normal liver tissue. Interestingly, the presence of ninjurin mRNA transcripts was detected with high intensity in HCC tissues when combined with viral infection and cirrhosis, but not with a normal liver or HCC tissue unrelated with viral infection and cirrhosis. We produced a N-terminal part of recombinant ninjurin protein, as well as a monoclonal antibody specific to this polypeptide. The intensity of immunohistochemical staining of the liver tumor tissue, and regenerating tissue for the ninjurin protein, was stronger than that of normal liver tissue. These results suggest that ninjurin may play an important role in the development of HCC combined with cirrhosis and viral infection.
Assuntos
Carcinoma Hepatocelular/metabolismo , Moléculas de Adesão Celular Neuronais/biossíntese , Hepatite Viral Humana/metabolismo , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/metabolismo , Fatores de Crescimento Neural/biossíntese , Animais , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/genética , Moléculas de Adesão Celular Neuronais/genética , Hepatite Crônica/complicações , Hepatite Crônica/genética , Hepatite Crônica/metabolismo , Hepatite Viral Humana/complicações , Hepatite Viral Humana/genética , Humanos , Immunoblotting , Imuno-Histoquímica , Fígado/anatomia & histologia , Fígado/patologia , Fígado/fisiologia , Fígado/fisiopatologia , Cirrose Hepática/complicações , Cirrose Hepática/genética , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/genética , Fatores de Crescimento Neural/genética , RNA/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Células Tumorais Cultivadas , Regulação para CimaRESUMO
The complete genomic DNA sequence of mouse ninjurin gene has been cloned and sequenced by screening a bacterial artificial chromosome (BAC) library of mouse 129/SvJ genomic DNA. The mouse ninjurin gene comprises four exons and the translatable sequences are included in the first three exons. The putative promoter region of the mouse ninjurin gene lacks the consensus "CAAT" or "TATA" sequence. Nonetheless, it has demonstrated the promoter activity in transient transfection experiment using the construct containing putative promoter sequence of mouse ninjurin and reporter gene. The nucleotide sequence of the putative promoter region shows 83% homology with the corresponding DNA sequence of human ninjurin gene that had been previously reported, and reveals a high degree of conservation between the two species. Analysis of the DNA sequence identified the putative promoters and the binding sites for a variety of transcription factors of mouse ninjurin.
