The Use of L-Glucose in Cancer Diagnosis: Results from In Vitro and In Vivo Studies

Background: Cancer cells are characterized by metabolic heterogeneity. Although many research groups make efforts to analyze this heterogeneity, little attention has been paid to cancer cells utilizing otherwise unusable substrates as fuel for tumor development. Of the two stereoisomers of glucose, D-glucose but not L-glucose, the mirror image isomer of D-glucose is abundantly found in nature. D-glucose is the human body's key source of energy through aerobic respiration. However, data from in vitro and in vivo studies examining the ability of cancer cells to take up L-glucose are scarce. Objectives: The present mini-review aims to present current literature data on the role of L-glucose in cancer diagnosis based on in vitro and in vivo studies. Methods: The MEDLINE, EMBASE, and the Cochrane Library with restrictions to articles in English language databases were searched to retrieve available data. Results: There are limited data in the literature regarding in vitro and in vivo studies that examined the ability of cancer cells to take up L-glucose. Research work so far has shown that that the binding of a fluorescent detector to an L-glucose molecule produced a fluorescent probe that was specifically taken up by malignant cancer cells, thus providing a unique method for their detection. Conclusion: Given that L-glucose is taken up by cancer cells, L-glucose fluorescent probes can be a useful tool for visualization and characterization of cancer cells. More research on the potential biologic effects of L-glucose in cancer is necessary.