Antimetastatic and antitumor activity of a derivative of neocarzinostatin: an organic solvent- and water-soluble polymer-conjugated protein.

A highly lymphotropic derivative of a proteinaceous antitumor agent, Neocarzinostatin, was prepared by chemical conjugation of a water-soluble synthetic poly(maleic acid)-styrene oligomer. The derivative of 2.5 X 10(4) dalton exhibited a strong antitumor activity against AH109A and DBLA-6 as well as antimetastatic activity against metastatic AH109A with which experimental lymphatic metastasis was produced in rats. An increased lipophilicity and molecular weight of the derivative appear to be responsible for its improvement as lymphotropic antimetastatic agent.