The nuclear pore complex protein Nup88 is overexpressed in tumor cells

It has been previously shown (J. Schneider et al., Br, J, Cancer; 77: 1015- 1020, 1998) that an antibody directed against Candida albicans proteins (C6 ) recognizes specifically a protein in human ovarian tumors, We have now pe rformed an immunoscreening of a human cDNA library using this antibody and identified the antigen as Nup88, a protein localized preferentially at the nuclear membrane and probably implicated in nucleocytoplasmic transport. Ou r results show that Nup88 is strongly expressed in a series of human tumor cell lines compared with nontransformed cell lines at the RNA and the prote in levels. Furthermore, we observed that in 76% of 21 ovarian tumors analyz ed, the protein is also overexpressed in malignant tissue when compared wit h healthy adjacent tissue. Nup88 may, therefore, be considered as a putativ e marker for tumor growth and is probably related to increased cell cycling .