Adenosine is an endogenous purine nucleoside, which has an
important role in many physiological processes. A number of studies
have shown solid tumors experience severe necrosis due to the
rapid growth of cancer cells and the fast rate of cell metabolism.
As a result of tissue hypoxia, adenosine concentration in the extracellular
fluid of solid tumors increases. Also, this enhancement of
adenosine concentration lead to disorder in anti-tumor immune
response function and consequently tumor cells stay alive. Therefore,
adenosine can act as a tumor-marker and its concentration in
the urine can be determined to monitor the progress ofthe diseases
[11]. Huizenga et al