Isolation of an ascitic oncodevelopmental protein exhibiting high sequence homology with calcium-binding protein MRP8.

A human oncodevelopmental protein (ODP) with a molecular size of 28 kDa was isolated, employing malignant ascitic fluid of an advanced mixed mesodermal tumor of the uterus, by anti-ODP coupled Affi-Gel 10 column chromatography, followed by preparative PAGE. The final preparation obtained with this procedure gave a single band exhibiting reactivity with an anti-ODP antibody on analytical sodium dodecyl sulfate-PAGE. The sequence of the first 20 N-terminal amino acids of this protein is identical with those of both the cystic fibrosis protein and Ca-binding protein MRP8 except at position 17, for which no result was obtained. Sequence analysis suggested that the protein shows 90% sequence homology with both these proteins.