New ribonuclease tandem enzyme, useful for treating tumors, comprising 2 ribonuclease units connected covalently through a peptide linker

摘要

Ribonuclease-tandem enzyme (I), comprising 2 or more ribonuclease (RNase) units bonded covalently through a peptide linker, is new. An independent claim is included for a method for preparation of (I). ACTIVITY : Cytostatic. MECHANISM OF ACTION : Degradation of tumor cell RNA. The tandem RNase in which the peptide linker was Gly(Pro)6Gly had activity against yeast RNA 50% of that of the monomeric enzyme, but its IC50 for inhibiting proliferation of K562 cells was 38 mu M, contrast over 200 mu M for the monomeric enzyme.