THE BACTERIAL COLICIN ACTIVE AGAINST TUMOR-CELLS IN-VITRO AND IN-VIVOIS VEROTOXIN-1

We have identified verotoxin 1 (VT1) as the active component within an antineoplastic bacteriocin preparation from Escherichia coli HSC10 st udied over two decades, Recombinant VT1 can simulate the toxicity of a nticancer proteins (ACP), and the antineoplastic activity of ACP (and VT1) was abrogated by treatment with anti-VT1 antibody, Similarly, VT1 mimics the protective effect of ACP in a murine metastatic fibrosarco ma model, Prior immunization with VT1 B subunit prevents the effect of VT1 or ACP in this model, The activity of ACP against a variety of hu man ovarian cell lines was mimicked by VT1, and multidrug-resistant va riants were significantly hypersensitive, Primary ovarian tumors and m etastases contain elevated levels of globotriaosylceramide compared wi th normal ovaries, and overlay of frozen tumor sections showed selecti ve VT binding to tumor tissue and the lumen of invading blood vessels, Our contention that VT1 could pro,ide an additional approach to the m anagement of certain human neoplasms is discussed.