Putative molecular signatures for the imaging of prostate cancer

Prostate cancer is the most common cancer among men worldwide and is the second leading cause of death among those over 50 years of age in the USA. However, many men who develop a prostate tumor never exhibit symptoms in the early stage of the disease or even before it spreads to other parts of the body, such as bones and lymph nodes. Therefore, the successful prevention and treatment of prostate cancer relies on the early and accurate detection of the disease. Although prostate-specific antigen has been extensively used as a serum biomarker to detect prostate tumors in the past 20 years, this screening method has suffered from a lack of specificities and sensitivities, despite its wide use. Furthermore, fluorine-18-labeled fluorodeoxyglucose, a radiopharmaceutical useful in the detection (using PET) of various solid tumors, is not accurate for imaging cancer of the prostate. Therefore, there is an underlying necessity to discover upregulated tumor-specific markers that may serve as molecular targets for the imaging of prostate cancer. This review summarizes the most recent advances made in the discovery of tumor-specific signatures that could be useful for imaging and accurate detection of prostate cancer, using the tools of bioinformatics, genomics, proteomics and metabolomics approaches. Also introduced is the recent development of a few promising techniques, such as functional MRI, to facilitate the detection of prostate tumor signatures.