The vanadyl chelate bis(acetylacetonato)oxovanadium(iv) increases the fractional uptake of 2-(fluorine-18)-2-deoxy-d-glucose by cultured human breast carcinoma cells

Abstract

Detection of breast cancer by positron emission tomography (PET) imaging with 2-(fluorine-18)-2-deoxy-D-glucose (FDG) as the tracer molecule is limited in part by both tumor dimension and metabolic activity. While some types of aggressive breast cancers are associated with a high capacity for FDG uptake, more indolent breast cancers are characterized by low FDG uptake. Moreover, detection of malignant lesions in most clinical settings requires tumor dimensions ≥10 mm. Development of a method to increase the fractional uptake of FDG by cancer tissue would provide a means to detect smaller tumors. However, there is no clinically available pharmacologic reagent known to enhance the preferential uptake of FDG by cancer tissue. Because the vanadyl (VO²⁺) chelate bis(acetylacetonato)oxovanadium(IV) [VO(acac)₂] is known to enhance cellular uptake of glucose, we have investigated whether VO(acac)₂ facilitates enhanced uptake of FDG by cultured human breast carcinoma cells. We observed that the fractional uptake of FDG by cultured human MDA-MB-231 carcinoma cells is increased in the presence of VO(acac)₂ in a dose dependent manner. Preliminary results with xenograft tumors generated in severely compromised, immunodeficient (SCID) female mice showed that VO(acac)₂ treatment of mice 3–4 h prior to FDG injection enhanced FDG uptake by the malignant tissue by a factor >2.0 compared with that by normal surrounding tissue.