In two cohorts of GC patients (discovery and validation), by adopting in-gel and gel-off salivary proteomics, Xiao et al. found that the combination of three proteins (cystatin B, CSTB; triosephosphate isomerase, TPI1; deleted in malignant brain tumors 1 protein, DMBT1) had abundances that were lower in GC saliva, differentiating GC from healthy control patients (p < 0.05; sensitivity = 85%; specificity = 80%; accuracy = 0.93) [100]. The gene discussed is CSTB; the disease is gastric cancer.