Proteomic analysis for early detection of ovarian cancer: a realistic approach?

Ovarian cancer is a multifaceted disease wherein most women are diagnosed with advanced stage disease. One of the most imperative issues in ovarian cancer is early detection. Biomarkers that allow cancer detection at stage I, a time when the disease is amenable to surgical and chemotherapeutic cure in over 90% of patients, can dramatically alter the horizon for women with this disease. Recent developments in mass spectroscopy and protein chip technology coupled with bioinformatics have been applied to biomarker discovery. The complexity of the proteome is a rich resource from which the patterns can be gleaned; the pattern rather than its component parts is the diagnostic. Serum is a key source of putative protein biomarkers, and, by its nature, can reflect organ-confined events. Pioneering use of mass spectroscopy coupled with bioinformatics has been demonstrated as being capable of distinguishing serum protein pattern signatures of ovarian cancer in patients with early- and late-stage disease. This is a sensitive, precise, and promising tool for which further validation is needed to confirm that ovarian cancer serum protein signature patterns can be a robust biomarker approach for ovarian cancer diagnosis, yielding improved patient outcome and reducing the death and suffering from ovarian cancer.

Insulin-dependent production of low-molecular-weight compounds that modify key enzymes in metabolism.

The mechanism by which the metabolic effects of insulin are transmitted is yet to be resolved. Second messengers mediating the action of insulin have been proposed and recently an insulin-dependent, peptide-like, heat- and acid-stable substance (Mr approx. 1000-3000) released from plasma membranes has been described which regulates the activity of key enzymes such as pyruvate dehydrogenase by altering its state of phosphorylation. It has been suggested that this material is the elusive second messenger of insulin and its discovery, generation, properties, isolation and mode of action are reviewed.