Study of interaction between NS3 serine protease of HCV and wild type P53 / 军事医学科学院院刊

Objective:To investigate the molecular interaction between non-structural protein 3 serine protease of hepatitis C virus(HCV)and wild type P53,and to lay the basis for elucidating the mechanism of oncogenesis of hepatocellular carcinoma(HCC)after infection of HCV.Methods:The recombinant plasmids,pGAD424-NS3,pGAD424-NS315aa- and pGAD424-NS330aa-,were constructed and the interaction between NS3 serine protease and its cofactor NS4A,the interaction between wild type P53 and NS3 serine protease and its N-truncated mutants were dectected qualitatively and quantitatively in yeast two-hybrid system.Results:The results indicated that interaction existed not only between full-length NS3 serine protease and P53,but also between N-truncated mutants of NS3 serine protease and P53.Furthermore,the difference between enzyme activity unit(IU)of β-gal induced by these interactions was not significant(P>0.05).Conclusions:NS3 serine protease of hepatitis C virus and its N-truncated mutants can interact with wild type P53,and the region of NS3 serine protease involved in the interaction may be located in its C-terminal,but not in its N-terminal.

Isolation and Sequencing the Differential Gene Fragments Expressed in Human Stomach Cancer Tissue / 中国肿瘤生物治疗杂志

Objective: Identification of the genes specially expressed in tumor cell but not in normal cell is important for understanding the molecular mechanisms of carcinogencsis. This study will focus on identification of differentially expressed gene fragments in human stomach cancer. Methods: By using the new developing mRNA differential display (DD) technique, genes fragments differentially expressed in stomach cancer tissues from a patient and the adjacent normal tissues beyond the tumor mass were studied. Results: Two differentially displayed complementary DNA fragments from stomach cancer tissues, scgl and scg2 (stomach cancer-associated gene, scg), cofirmed by Northern Blot, were cloned and sequenced. The nucleotide length of scgl is 194 base pairs and that of scg2 is 343 base pairs. After searching against GenBank databases by BLASTN, neither scgl nor scg2 had significant homological gene sequences with the known genes. Conclusion: These results suggested scgl and scg2 might be complementary DNA fragments of novel genes expressed in stomach cancer tissues, but not in normal tissues and may play a role in the occurrence and development of stomach cancer. Further characterization of full-length of these two complementary DNA fragments will be continued.