Drug therapies are often used effectively without their underlying mechanism being completely understood. We exploit the literature-based discovery paradigm to investigate these mechanisms and propose a discovery pattern that draws on semantic predications extracted from MEDLINE citations. The use of semantic predications and the discovery pattern provides a way to uncover previously unnoticed associations between pharmacologic and bioactive substances on the one hand and bioactive substances and disorders on the other. In this paper, we concentrate on research investigating the use of antipsychotic agents used for treatment of cancer. Our method resulted in five biomolecules that may provide a link between the antipsychotic agents and cancer: brain-derived neurotrophic factor, CYP2D6, glucocorticoid receptor, PRL, and TNF.