Abstract: The invention relates to a therapeutic system comprising (i) a radiolabelled antibody, which binds selectively to polymorphic epithelial mucin (PEM) such as the monoclonal antibody HMFG-1, and (ii) a chemotherapeutic agent, such as Taxotere®. The radiolabelled antibody and chemotherapeutic agent are administered in combination with one another to produce a synergistic therapeutic effect.

Abstract: A conjugate compound comprises a cell-specific portion, such as an antibody specific to tumour cell antigens, and an enzymatically active portion which will cleave a cyanogenic compound to release cyanide. Enzymes such as &bgr;-glucosidases are suitable. The cyanogenic compound, e.g. amygdalin or some other plant-derived saccharide, is administered after the conjugate. Intravesical (intra-bladder) administration is preferred (for bladder cancers) and forms a further aspect of the invention, whether the compound is cyanide-liberating (as above) or suitable for therapy or imaging in any other way.