Scientists have found that cancer patients produce antibodies that target abnormal glycoproteins (proteins with sugar molecules attached) made by their tumors. The result of this work suggests that antitumor antibodies in the blood may provide a fruitful source of sensitive biomarkers for cancer detection. The study, supported in part by the National Cancer Institute (NCI), part of the National Institutes of Health, appears in the Feb. 15, 2010 issue of the journal Cancer Research.