Definition

A cancer vaccine composed of a heat-killed, recombinant form of the yeast Saccharomyces cerevisiae that is genetically modified to express the transcription factor brachyury protein, with potential antineoplastic activity. Upon subcutaneous administration, the brachyury-expressing yeast vaccine GI-6301 is recognized by dendritic cells, processed, and presented by Class I and II MHC molecules on the dendritic cell surface. This elicits a targeted CD4+ and CD8+ T-lymphocyte-mediated immune response. This process kills brachyury-expressing tumor cells. Brachyury is overexpressed in a variety of tumor types and plays an important role in cancer progression and metastasis.