VALIDATION OF FLUORESCENT DEOXYGLUCOSE (2-NBDG) IN TUMORS

DESCRIPTION (provided by applicant): A new fluorescent analogue of d-glucose, 2-[N-(7-nitrobenz-2-oxa-1,3-diaxol-4-yl)amino]-2- deoxyglucose (2-NBDG), was recently developed, but has not been characterized as a marker of glucose uptake in cancer cells. Validating this new tracer as a glucose analogue for optical imaging of superficial tumors may have a major impact on clinical and preclinical imaging of superficial tumors. If this new tracer is shown to behave similarly to the 18-fluorine-labeled 2-deoxyglucose (FDG), which is becoming the gold standard for metabolic imaging of tumors by positron-emission topography (PET), we may change the way superficial tumors are detected and diagnosed and produce a low cost screening method for early detection of superficial tumors. This validation may also have a major impact on animal studies since it would be the only glucose analogue validation for metabolic imaging in small animals. The overall goal of the project is to validate first the use of 2-NBDG as a marker of malignant tumor cells (Phase I) and then to develop in vivo methods and fluorescence optical instrumentation, for commercialization, that can be used to\ economically monitor 2-NBDG uptake via simple optical instrumentation (Phase II). Two Specific Aims proposed for Phase I: 1) to assess and characterized the uptake properties of the fluorescent glucose analogue, 2-NBDG, in model malignant tumor cell lines and in normal, non-malignant cells in vitro using fluorescence microscopy and spectrofluorimetry to elucidate the kinetic properties of the 2-NBDG uptake process in selected model malignant tumor cell lines (three lines) and in normal, non-malignant cells, and 2) to validate the use of the fluorescent glucose analogue, 2-NBDG, as a probe to identify malignant tumor cells by directly comparing the uptake of 2-NBDG with the uptake of radiolabeled 2-dexoyglucose (an established "gold" standard), by radioisotopic analysis, in the same cell lines; and initial uptake in animal tissues. By comparing 2-NBDG uptake with that of the standard, radiolabeled analogue, the use of 2-NBDG as a reliable probe for each cell line will be validated. The end points for assessing successful completion of Phase I is the demonstration of uptake of 2-NBDG in tumor cells comparable to radiolabeled 2-deoxyglocose. Following a successful completion of this phase, we propose to study the feasibility of in-vivo imaging of 2-NBDG in mice models of superficial tumors, and develop instrumentation to detect these tumors non-invasively.