Abstract: Exosomes were purified from the sera of patients with gastric cancer and healthy subjects by using size-exclusion chromatography, and novel markers were obtained through mass spectrometry. In the patients with gastric cancer, 40 proteins with enhanced expression and 4 proteins with decreased expression can be suitable markers for detecting gastric cancer. Particularly, the detailed analysis of CA1, including its function, showed that gastric cancer could be detected with high sensitivity.

Abstract: An object of the invention is to provide a method for detecting cancer in a simple and highly accurate manner, and a reagent that can be used in the method. A method for detecting cancer (excluding renal cell cancer), which comprises measuring the level of Azurocidin (AZU1) in a sample, in which it is determined that cancer is detected when a measured value exceeds a preset reference value. The cancer is preferably selected from the group consisting of stomach cancer, breast cancer, colorectal cancer, and lung cancer. A reagent containing an antibody that specifically recognizes AZU1 is used in detecting cancer (excluding renal cell cancer).

Abstract: Provided is a method wherein an affected tissue and a normal tissue obtained from the vicinity of the affected tissue are left at rest in a culture medium, and a disease-specific biomarker is searched for in an exudate therefrom. A biomarker specific to renal cell carcinoma has been found by this method.